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The benefits of wearing a compression sleeve after ACL reconstruction
Abstract
It was the purpose of the present study to examine the possibility of increased muscle coordination after anterior cruciate ligament (ACL) reconstruction through the wearing of a compression sleeve.
Thirty-six patients were studied who had undergone unilateral ACL reconstruction at least 12 months previously. All subjects were required to perform a 10-cm standing drop jump from an elevated platform onto a force plate, to land on one leg, and thereafter maintain a one-legged balance for 25 s. This task was repeated three times without and three times with an elastic compression sleeve worn on the reconstructed limb. For analysis, the task was partitioned into a landing phase (150 ms), an adjusting phase (10s), and a balancing phase (10s). The peak impact loadings were measured in each direction (Fx, Fy, and Fz) during landing, while force-time integrals (intFz, intFy, and intFz) and root mean square (RMS) error of these forces were calculated for the adjusting and balancing phases. The path length and RMS of the center of pressure coordinates (Ax and Ay) were obtained for the adjusting and balancing phases combined.
Drop landings with the bandage produced significantly larger (P < 0.001) peak ground reaction forces in the vertical and anteroposterior direction, suggesting increased subject confidence in their knee. Wearing the knee bandage also enabled the patients to reduce all measured parameters in the anteroposterior direction (rmsFx, intFx, rmsAx) during both the adjusting and balancing phases (P < 0.001 ). A significant reduction in the center of pressure path length further indicated an enhanced steadiness during the one-legged stance.
It was concluded that a compression sleeve improved the total integration of the balance control system and muscle coordination.
... Ergogenic compression garments have been utilized in attempts to sustain or improve joint kinematics (Lee et al., 2016;Mills et al., 2015;Varela-Sanz et al., 2011) and/or limb stability and balance control (Kuster et al., 1999;Michael et al., 2014;Pearce et al., 2009). While earlier research supported that any motor control/balance improvements were due to physiological effects of compression on venous flow (Sigel et al., 1975) and/or unnecessary motion reduction (Blair et al., 1995), subsequent research has challenged these explanations (Harris, 1996). ...
... This information is usually defined with the umbrella term proprioception. Proprioception can mediate joint function and sensation, ensuring that the musculoskeletal system is in balance to overcome any overload on muscles and joints (Kuster et al., 1999). It has also been shown to inform postural control and instigate balance correction movements (Inglis et al., 1994). ...
... To date, there is no consensus on how specific garment attributes may influence these effects. Neuromuscular improvements have been observed in participants wearing items such as knee sleeves (Kuster et al., 1999), stockings (Varela-Sanz et al., 2011), full length compression tights (Michael et al., 2014), and even full-body lycra garments (Rennie et al., 2000). These many clothing types can cover various combinations of joints and lower-body segments, which makes studying discrete effects challenging. ...
Compression garments have been used to minimise injury risk, through improvements in stability and joint positioning; yet, it is unclear whether there is an optimal length or tightness of these garments that may maximise observed benefits. This study measured the effect of three different garment types, at two different tightness levels, on lower extremity stability and alignment during a forward lunge movement. Sixteen healthy adults (7 female, 9 male; 24.3 ± 2.9 years) were recruited as participants. Stability of the lead foot, as well as lower body joint kinematics, were recorded using an Oqus 12-camera system, surrounding participants as they executed three forward lunges onto a Matscan pressure mat under seven compression conditions (Control, Light/Heavy Calf, Light/Heavy Socks, Light/Heavy Leggings). Mean minimum time-to-boundary (mmTtB) (derived from centre of pressure measures) and frontal plane kinematics (lateral pelvic tilt, knee valgus, ankle inversion/eversion) were used to assess the effect of garment tightness and length on lunge stability and joint alignment, respectively. A significant effect of tightness on mmTtB was observed (F (1,105) = 8.192; p = .005, η ² = .072), with Heavy garments eliciting longer mmTtB compared to their corresponding Light (-.18 ± .06 s; p = .015) or Control (-.28 ± .09 s; p = .007) conditions. No significant effects of garment tightness or length on lower body kinematics were evident. The results of this study suggest stability during a forward lunge is improved through the use of tight-fitted compression garments.
... The main focus of early research using wearable garments (e.g., tapes, braces and compression garments) was related to injury and re-injury prevention [14][15][16]. Investigations centred on how disrupted proprioception could be enhanced by using wearable garments. For example, two studies investigated effects of strips and athletic tapes on joint movement position awareness [15,16] for injury prevention. ...
... Robbins et al. [15] suggested that the traction of the tape on the skin provided cutaneous sensory cues of plantar surface position to enhance anticipation of the foot position before contact with the floor. Similarly, effects of wearing compression garments (shorts and sleeves) on joint position sense [17] and postural regulation and balance during a single-leg landing task [14] were also tested. Kuster Lower-limb sensory stimulation strategies and postural regulation PLOS ONE | https://doi. ...
... Previous evidence of efficacy of different lower-limb stimulation strategies: Wearable Garments (WG), Textured Materials (TM) and application of Stochastic Resonance (SR) et al. [14] revealed that the compressive sleeve intervention reduced postural sway in the anteroposterior (AP) direction. It was argued that wearable garments such as tapes, compression garments, and braces could improve proprioception, specifically on improving judgment of ankle position and orientation of the plantar surface with respects to the leg [16,18]. ...
Systematic reviews of balance control have tended to only focus on the effects of single lower-limb stimulation strategies, and a current limitation is the lack of comparison between different relevant stimulation strategies. The aim of this systematic review and meta-analysis was to examine evidence of effects of different lower-limb sensory stimulation strategies on postural regulation and stability. Moderate- to high- pooled effect sizes (Unbiased (Hedges’ g) standardized mean differences (SMD) = 0.31–0.66) were observed with the addition of noise in a Stochastic Resonance Stimulation Strategy (SRSS), in three populations (i.e., healthy young adults, older adults, and individuals with lower-limb injuries), and under different task constraints (i.e., unipedal, bipedal, and eyes open). A Textured Material Stimulation Strategy (TMSS) enhanced postural control in the most challenging condition—eyes-closed on a stable surface (SMD = 0.61), and in older adults (SMD = 0.30). The Wearable Garments Stimulation Strategy (WGSS) showed no or adverse effects (SMD = -0.68–0.05) under all task constraints and in all populations, except in individuals with lower-limb injuries (SMD = 0.20). Results of our systematic review and meta-analysis revealed that future research could consider combining two or more stimulation strategies in intervention treatments for postural regulation and balance problems, depending on individual needs.
... Adding external stabilization of the knee by knee braces reduced likelihood of subsequent injury (7,8). Although literature reported that compressive sleeves improve knee proprioception and single-limb standing balance in subjects with ACL-reconstruction, but research on the effects of knee brace on dynamic balance is limited (9,10). ...
... Demographic characteristics of participants are shown in Table 1. The exclusion criteria for ACL-reconstructed subjects included any other orthopedic injuries (except meniscal injuries), neurological and strength deficits, range of motion restriction, pain and joint effusion at the time of testing (8)(9)(10)(11). Subjects with ACLreconstruction had been advised by their surgeons to resume previous physical activities. Participants had the Tegner score of 8.5. ...
... Birmingham et al. reported no effect of brace on mediolateral COP sway in subjects with ACLreconstruction (9). Kuster et al. (10) found that wearing knee bandage had no significant effect on the one legged stance balance control mediolateral sway amplitude. ...
Background: The current study aimed to evaluate the postural control in patients underwent anterior cruciate ligament recon- struction pre and post wearing functional knee brace. Methods: Eighteen athletes undergone unilateral anterior cruciate ligament reconstruction included in the study. They had uni- lateral anterior cruciate ligament reconstruction at least six months before session test. Postural control was assessed pre and post wearing custom-fit functional knee brace using a posturographic platform prokin 254. The balance tests included: 1) standing on prokin platform with eyes open/closed on anterior cruciate ligament reconstruction limb, 2) standing on prokin platform with eyes open/closed on both limbs. The standard deviation (SD) of body sway along the anteroposterior (AP) and mediolateral (ML) axis, mean velocity of center of pressure (COP) along AP/ ML axis and the area ellipse (measured in 2 mm) were calculated. Results: Results of the paired T-test revealed a significant eect on selected postural control variables for the brace conditions es- pecially in low challengeable conditions (double leg, eyes open test situations) (P < 0.05). But in high challengeable conditions this eect was not significant. Conclusions: Functional knee brace improved postural control in the simple balancing task in the subjects with anterior cruciate ligament reconstruction. But this improvement in more dicult balancing task was limited.
... Groin injury can be a debilitating experience for athletes competing in sports that require quick acceleration and sudden directional changes. Groin pain is common to a broad range of injuries occurring in the abdominal, hip, pelvic, or thigh areas (15,24), although is most frequently associated with muscle strain (2,14,36). While approximately 5% of the active population seen for clinical treatments report groin pain, groin injury accounts for a disproportionately large amount of lost competition time in athletes (3). ...
... Whether EMG activity and neuromuscular control changes are related is unclear. Subjective evaluations of brace use are generally positive, with subjects feeling more confident, less pain due to delayed-onset muscle soreness (DOMS), and reporting that the brace enhanced test performance (7,21,24). ...
... Subjective evaluations of the compression shorts used in the present study are similar to those reported previously for neoprene compression sleeves (7,21,24). The Coreshorts™ prototype used in the present study were designed to offer multi-directional support, offering increased resistance to excessive motion at the hip joint in each plane of motion. ...
... Therefore, training strategies such as balance training, resistance training or warm-up programs, can be implemented to minimize inter-limb balance asymmetries, improve balance control and reduce the relative risk of sports-related non-contact injury (Bishop et al., 2018;Pardos-Mainer et al., 2019;Madruga-Parera et al., 2020). Affordable external devices that interact with cutaneous receptors such as compression garments (CG) can also acutely improve balance control (Kuster et al., 1999;Michael et al., 2014;Woo et al., 2017;Baige et al., 2020). The constriction provided by CG acts as a mechanically supportive framework that can activate interacting cutaneous mechanoreceptors that individually would not have been activated (Baige et al., 2020), thus improving movement accuracy during tasks that include a large somatosensory component (Hasan et al., 2016;Ghai et al., 2018;Broatch et al., 2021) and offering a potential benefit in reducing inter-limb balance asymmetries. ...
... When wearing CG, frictional forces that activate both slow and fast-adapting cutaneous mechanoreceptors are applied to the skin, which can improve joint position sense and balance control (Kuster et al., 1999;You et al., 2004;Cameron et al., 2008;Michael et al., 2014;Woo et al., 2017;Baige et al., 2020;Broatch et al., 2021). In the present study, there was a great heterogeneity in the ability of participants to benefit from CG wearing to reduce inter-limb balance asymmetries. ...
This special issue adresses acute and chronic changes in postural control in
response to different physiological states and external environmental conditions.
... Such sleeves do not limit range of motion but are thought to influence sensorimotor control [16], potentially leading to enhanced movement patterns or knee joint position sense [16][17][18]. Wearing knee sleeves may improve the individual's knee-related confidence [19][20][21]. Results of laboratory studies suggest that using such sleeves may improve gait-and function-related performance for people with symptomatic knee osteoarthritis [18], knee-healthy participants [20,22] and elite athletes [23]. Knee sleeves may be at the cost of reduced knee flexion during drop landing, as shown in laboratory-based study of immediate effects with knee-healthy participants [22]. ...
... Knee sleeves may be at the cost of reduced knee flexion during drop landing, as shown in laboratory-based study of immediate effects with knee-healthy participants [22]. Kuster et al. [21] reported that wearing an elastic sleeve led to increased vertical ground reaction (GRF) during a drop jump for participants with ACL reconstructions, as well as improved balance, evident with enhanced steadiness during the one-legged stance. Little is known about the potential influences of knee sleeves on movement patterns at the knee for participants with ACL reconstruction, particularly knee flexion and knee joint moments, across an extended period of use. ...
Background
Elastic knee sleeves are often worn following anterior cruciate ligament reconstruction (ACLR) but their effects on movement patterns are unclear.
Aim
To determine the immediate and six-week effects of wearing a knee sleeve on biomechanics of the knee during a step-down hop task.
Methods
Using a cross-over design, we estimated sagittal plane knee kinematics and kinetics and stance duration during a step-down hop for 31 participants (age 26.0 [SD 6.6] years, 15 women) after ACLR (median 16 months post-surgery) with and without wearing a knee sleeve. In a subsequent randomised clinical trial, participants in the ‘Sleeve Group’ (n = 9) then wore the sleeve for 6 weeks at least 1 h daily, while a ‘Control Group’ (n = 9) did not wear the sleeve. We used statistical parametric mapping to compare (1) knee flexion/extension angle and external flexion/extension moment trajectories between three conditions at baseline (uninjured side, unsleeved injured side and sleeved injured side); (2) within-participant changes for knee flexion angles and external flexion/extension moment trajectories from baseline to follow-up between groups. We compared discrete flexion angles and moments, and stance duration between conditions and between groups.
Results
Without sleeves, knee flexion was lower for the injured than the uninjured sides during mid-stance phase. When wearing the sleeve on the injured side, knee flexion increased during the loading phase of the stance phase. Discrete initial and peak knee flexion angles increased by (mean difference, 95% CIs) 2.7° (1.3, 4.1) and 3.0° (1.2, 4.9), respectively, when wearing the knee sleeve. Knee external flexion moments for the unsleeved injured sides were lower than the uninjured sides for 80% of stance phase, with no change when sleeved. The groups differenced for within-group changes in knee flexion trajectories at follow-up. Knee flexion angles increased for the Control group only. Stance duration decreased by 22% for the Sleeve group from baseline to follow-up (-89 ms; -153, -24) but not for the Controls.
Conclusions
Application of knee sleeves following ACLR is associated with improved knee flexion angles during hop landing training. Longer term (daily) knee sleeve application may help improve hop stance duration, potentially indicating improved hop performance.
Trial registration
The trial was prospectively registered with the Australia New Zealand Clinical Trials Registry No: ACTRN12618001083280, 28/06/2018. ANZCTR
... CG use reduced the ML displacement of COP by 4.2% relative to the AP displacement and absolute error of JPS. Studies have reported that CG use can enhance the perception of somatosensory information and positively influence balance control by reducing body sway during quiet standing [18,41,42]. These results are somewhat inconsistent with those reported in the present study. ...
... These results are somewhat inconsistent with those reported in the present study. The beneficial effects of CGs on proprioception control may be most pronounced among older adults, injured individuals [18,41] and high-level athletes [42]. By comparison, ordinarily active individuals such as healthy and non-injured individuals and nonelite/recreational athletes do not achieve improved proprioception control with CG use [43,44]. ...
Fatigue is a major cause of exercise-induced muscle damage (EIMD). Compression garments (CGs) can aid post-exercise recovery, therefore, this study explored the effects of CGs on muscular efficacy, proprioception, and recovery after exercise-induced muscle fatigue in people who exercise regularly. Twelve healthy participants who exercised regularly were enrolled in this study. Each participant completed an exercise-induced muscle fatigue test while wearing a randomly assigned lower-body CG or sports pants (SP); after at least 7 days, the participant repeated the test while wearing the other garment. The dependent variables were muscle efficacy, proprioception (displacements of center of pressure/COP, and absolute error), and fatigue recovery (muscle oxygen saturation/SmO2, deoxygenation and reoxygenation rate, and subjective muscle soreness). A two-way repeated measure analysis of variance was conducted to determine the effect of garment type. The results indicated that relative to SP use, CG use can promote muscle efficacy, proprioception in ML displacement of COP, and fatigue recovery. Higher deoxygenation and reoxygenation rates were observed with CG use than with SP use. For CG use, SmO2 quickly returned to baseline value after 10 min of rest and was maintained at a high level until after 1 h of rest, whereas for SP use, SmO2 increased with time after fatigue onset. ML displacement of COP quickly returned to baseline value after 10 min of rest and subsequently decreased until after 1 hour of rest. Relative to SP use, CG use was associated with a significantly lower ML displacement after 20 min of rest. In conclusion, proprioception and SmO2 recovery was achieved after 10 min of rest; however, at least 24 h may be required for recovery pertaining to muscle efficacy and soreness regardless of CG or SP use.
... Therefore, training strategies such as balance training, resistance training or warm-up programs, can be implemented to minimize inter-limb balance asymmetries, improve balance control and reduce the relative risk of sports-related non-contact injury (Bishop et al., 2018;Pardos-Mainer et al., 2019;Madruga-Parera et al., 2020). Affordable external devices that interact with cutaneous receptors such as compression garments (CG) can also acutely improve balance control (Kuster et al., 1999;Michael et al., 2014;Woo et al., 2017;Baige et al., 2020). The constriction provided by CG acts as a mechanically supportive framework that can activate interacting cutaneous mechanoreceptors that individually would not have been activated (Baige et al., 2020), thus improving movement accuracy during tasks that include a large somatosensory component (Hasan et al., 2016;Ghai et al., 2018;Broatch et al., 2021) and offering a potential benefit in reducing inter-limb balance asymmetries. ...
... When wearing CG, frictional forces that activate both slow and fast-adapting cutaneous mechanoreceptors are applied to the skin, which can improve joint position sense and balance control (Kuster et al., 1999;You et al., 2004;Cameron et al., 2008;Michael et al., 2014;Woo et al., 2017;Baige et al., 2020;Broatch et al., 2021). In the present study, there was a great heterogeneity in the ability of participants to benefit from CG wearing to reduce inter-limb balance asymmetries. ...
Sensory cues provided by compression garments (CG) can improve movement accuracy and potentially reduce inter-limb balance asymmetries and the associated risk of injury. The aim of this study was to analyze the effects of CG wearing on inter-limb balance asymmetries. The hypothesis was that CG would reduce inter-limb balance asymmetries, especially in subjects with high level of asymmetries. Twenty-five sportsmen were recruited. They had to stand as motionless as possible in a one-leg stance in two postural tasks (stable and unstable), while wearing CG or not. Asymmetry indexes were calculated from center of foot pressure parameters. The effects of CG wearing were analyzed according to participants’ baseline level of asymmetry (i.e., without wearing CG) with correlation analyses. A qualitative analysis was also performed after a dichotomization procedure to check for a specific influence of CG on the dominant and non-dominant leg. Inter-limb balance asymmetries were reduced with CG in participants with high levels of asymmetries at baseline. However, asymmetries were increased with CG in participants with low levels of asymmetries at baseline. The dominant leg was more affected by this negative effect. CG wearing could reduce inter-limb balance asymmetries and the related injury risk in subjects with high levels of inter-limb balance asymmetries at baseline. Nevertheless, CG should not be used in individuals with low baseline balance asymmetries since it can increase asymmetries in these subjects, likely by confusing and overloading the sensorimotor processing on the dominant leg.
... Actually, the overall constriction provided by compression garments acts as a mechanically supportive framework sensitive to body movements that can activate interacting cutaneous mechanoreceptors that individually would not have been activated. Hence, compression garments can enhance the perception of somatosensory information and influence balance control positively by reducing body sway during quiet standing (Kuster et al., 1999;Michael et al., 2014;Woo et al., 2017Woo et al., , 2018. ...
... These beneficial effects of compression garments on balance control would be most pronounced among elderly and injured subjects (Kuster et al., 1999;You et al., 2004;Palm et al., 2012;Woo et al., 2018) and high-level athletes (Michael et al., 2014). These results suggest that only subjects with either sensory deficits, such as elderly and injured subjects, or exceptional sensory acuity and/or sensory reweighting mechanisms, such as high-level athletes (Paillard, 2017(Paillard, , 2019, would be able to benefit from compression garments to improve balance control. ...
There is controversy about the influence of compression garments on balance control. A positive influence was reported in elderly and injured individuals, whereas no beneficial effects were observed in young healthy active subjects, which is likely due to the large
inter-individual differences in these subjects. Hence, this study investigated the acute effects of compression garments on balance control in young healthy active subjects by addressing the issue of heterogeneity of individuals’ responses to the wearing of compression garments. Thirteen young, healthy, active subjects were recruited. They stood on a force plate which recorded the center of foot pressure displacements in a monopedal stance with the eyes closed and on a wobble board with the eyes open, while wearing compression garments or not. Statistics were first calculated with the data from the whole sample. A hierarchical cluster analysis was also performed in order to categorize the participants’ behaviors into subgroups with similar characteristics. The whole group analysis showed that there were no significant effects attributed to compression garments. The clustering analysis identified distinct and homogeneous subgroups of participants. Only participants who swayed the more at baseline benefited from the wearing of compression garments to improve their balance control. These participants might have either a gravity-dependent preferred sensorimotor strategy with
an exploratory postural behavior or poorer balance/proprioceptive abilities. Since poor balance control is a predictor of sports injury risk, wearing compression garments during sports practice could be viewed as a potential prevention strategy for individuals at risk.
Full text: https://www.frontiersin.org/articles/10.3389/fnhum.2020.582514/full
... 5 It has been suggested that improvements in stability and joint control associated with the use of knee orthoses are associated with enhanced joint proprioception 5 and can enhance balance performance. 6,7 Evidence to support this is however inconsistent. ...
... A limited number of authors have investigated the relationship between kinesthetic awareness and functional performance and results are generally inconclusive. Birmingham et al. 6 and Kuster et al. 7 indicated that knee orthoses enhance both kinesthetic awareness and balance. Some authors report improvement in kinesthetic awareness with no improvement in balance. ...
Introduction
Conflicting evidence exists regarding the effects of knee orthoses on proprioception. One belief is that pressure applied by orthoses heightens kinesthetic awareness and that this affects balance. This study aimed to investigate the effects of two different orthosis designs on kinesthetic awareness and balance in healthy individuals.
Methods
Twenty individuals (13 women) participated in this case series study. Each was tested wearing 1/no orthosis, 2/soft elastic orthosis and 3/non-elastic jointed orthosis. Pressure under orthoses was recorded. Kinesthetic awareness was investigated by testing joint position sense and threshold to detection of passive motion. Balance was tested using a modified sensory organization test.
Results
Non-elastic jointed orthoses applied the greatest pressure to the knee. With non-elastic jointed orthoses, threshold to detection of passive motion was significantly poorer for pooled results ( p = 0.02) and when the start position of the knee was 70° (mean threshold = 0.6°, 0.6°, 0.7° for no-orthosis, elastic and jointed-orthoses; p = 0.03). No major differences were observed in JPS or balance and correlation between proprioception and balance was poor.
Conclusions
There may be a limit to the amount of pressure that should be applied to the knee joint by an orthosis. Exceeding this limit may compromise kinesthetic awareness.
... In more challenging conditions involving visual occlusion, compression garments (shorts) improved the total time in unipedal standing balance [21]. For young athletes with lower extremity injuries, studies have shown that compression via orthoses and sleeves improved uni -and bi-pedal balance performance [2,10,19,22,23]. ...
... What might be the mechanism behind the enhancement of proprioceptive information from wearing such external attachments and garments? The tactile and proprioceptive sub-systems play a role in regulating balance by responding to information from fine touch, compression, contortion, vibration, pressure and changes in joint angles that is picked up by somatosensory system components [19]. One possibility is that external appliances (e.g. ...
Study aim: The aim of this study was to evaluate the effects of training while wearing socks differing in compression level (clinical, sub-clinical, regular) on performance of static and dynamic balancing and agility tasks in healthy, physically active people. We sought to understand whether socks with different compression properties supported postural regulation and agility task performance by enhancing somatosensory perception, unskewed by specific age range effects. Material and methods: Participants comprised 61 adults aged 18-75 years, divided into three groups (two experimental groups wearing clinical or sub-clinical level compression socks, and one control group wearing regular non-compression socks during training). An 8-week (2 × 1h per week) intervention programme was administered to train static and dynamic balance and postural control, leg strength and agility. Results: A mixed model ANOVA revealed no differences in static and dynamic balance and postural control and agility performance between clinical, sub-clinical, and control groups before and after training. All groups significantly improved their test performance, suggesting that training had some benefit on motor performance. Conclusions: These results raised interesting questions requiring further investigation to examine the effects of wearing socks (with and without different levels of compression) on motor behaviours in specific groups of elderly vs. young participants, in physically active vs. less physically active people, and in performance settings outside standardized laboratory tests to study applications in natural performance environments.
... In a study by Kuster et al., 36 patients who had had ACL (anterior cruciate ligament) reconstruction performed a single-leg drop jump test from a 10 cm high platform and landed 20 cm in front of the platform. The dynamic balance in the single-leg standing position was evaluated for 25 seconds after landing 36) . Franz et al. measured the COP speed, COP sway, and ground reaction force of 25 healthy subjects who jumped from a 30 cm high step and landed on a force plate in front of them 37) . ...
... The other reasons that a hard brace is weaker for dynamic balance than a soft brace are considered to be the elastic sleeve in the soft brace and many compression and contact parts in a hard brace. Kuster et al. reported that dynamic balance improved with an attached compression sleeve for patients who underwent ACL reconstruction, according to the single-leg drop jump test 36) . In our study, brace A having an soft sleeve that covered surface (skin) of the knee joint with moderate pressure functioned better for neuromuscular reflex via skin mechanoreceptors 40)41) . ...
The purpose of this study is to examine the effect of knee bracing on static and dynamic balance (postural stability).Two knee braces were examined: soft type (A, “Short Runner Airmesh”) and hard type (B, “Townsend-Rebel TM5”). For thirteen collegiate American football players, three conditions – no bracing (Group N), attached brace A (Group A), and attached brace B (Group B) – were set. All subjects performed three tests: a) single-leg standing with eyes closed to measure static balance, b) forward single-leg drop jump with eyes open, and c) lateral single-leg drop jump with eyes open to measure their dynamic balance, by using Zebris PDM-S system. We measured two items: 1. total track length (mm) of center of pressure (COP) and 2. confidence ellipse area (mm2). The results showed a significant difference between the groups in COP total track length of lateral single-leg drop jump with eyes open, with Group N: 539.2±74.4, Group A: 552.0±66.5, and Group B: 566.2±54.7 (mm).Consequently, dynamic balance was shown to decrease when a knee brace was worn, and a hard type reduced dynamic balance more than a soft type. We suspected that bilateral uprights contacted the knee joint hindered the joint proprioception, during controlling the balance of the side movement after landing. Moreover, many compression and contact parts against the knee joint due to the hard shell and rigid straps of a hard type caused to reduce the dynamic postural stability.
... Redfern and Di Pasquale [4] and Sheehan and Gottschall [5] demonstrated that the risk of falling and slipping is higher for downhill walking than for level and uphill walking. This increased injury risk is caused primarily by high loads on the lower extremities' joints [6,7]. This more demanding task needs an optimal coordination control. ...
... During uphill walking the exercise is mainly concentric while during downhill walking the exercise is mainly eccentric. The eccentric forces applied to the tissues of the knee, produce a higher knee load [6,7]. The combination of increased coordinative demand and joints' load might lead to pain and increase injury risk during downhill walking [5,4,8]. ...
... Redfern and Di Pasquale [4] and Sheehan and Gottschall [5] demonstrated that the risk of falling and slipping is higher for downhill walking than for level and uphill walking. This increased injury risk is caused primarily by high loads on the lower extremities' joints [6,7]. This more demanding task needs an optimal coordination control. ...
... During uphill walking the exercise is mainly concentric while during downhill walking the exercise is mainly eccentric. The eccentric forces applied to the tissues of the knee, produce a higher knee load [6,7]. The combination of increased coordinative demand and joints' load might lead to pain and increase injury risk during downhill walking [5,4,8]. ...
Hiking is a backcountry activity suitable for people in every age. Pain and injuries are reported in hiking especially during downhill walking. This increased injury risk is caused primarily by high loads on the lower extremities’ joints and the optimal coordination control therefore required. Through the use of knee supports during hiking the injury risk might be reduced by, for example, improving proprioception. The purpose of this study was to determine the effect of wearing a knee sleeve and a knee brace on knee proprioception during a hiking simulation protocol on a treadmill. Twenty-four female sport students took part in this study. Joint position sense was measured without wearing any knee support, wearing a knee sleeve and wearing a knee brace at the beginning, after 30 minutes uphill walking and after 30 min downhill walking on a treadmill. Considering all tested subjects, without knee support the absolute repositioning error at the beginning was signifcantly better than the error after downhill walking (p=0.022) but no effect of the knee supports was found. Analysing only the subjects with a worsening in joint position sense after the activity, a signifcant improvement in joint position sense found wearing the sleeve and the brace after uphill and downhill walking (p<0.05).
... Compression garments attenuate longitudinal and anterior-posterior oscillation of muscles during maximal jumping, thereby lowering fatigue and elevating height during consecutive jumps [9,10]. Since compression garments activate tactile mechanoreceptors, reduce pre-synaptic inhibition [11] and enhance sensory feedback, proprioception is en- hanced [12,13] and balance improved [13]. In addition, compression stockings enhance maintenance of leg power after 10 km of running [14]. ...
... Compression garments attenuate longitudinal and anterior-posterior oscillation of muscles during maximal jumping, thereby lowering fatigue and elevating height during consecutive jumps [9,10]. Since compression garments activate tactile mechanoreceptors, reduce pre-synaptic inhibition [11] and enhance sensory feedback, proprioception is en- hanced [12,13] and balance improved [13]. In addition, compression stockings enhance maintenance of leg power after 10 km of running [14]. ...
This study examined the effects of different levels of compression (0, 20 and 40 mmHg) produced by leg garments on selected psycho-physiological measures of performance while exposed to passive vibration (60 Hz, amplitude 4-6 mm) and performing 3-min of alpine skiing tuck position METHODS: Prior to, during and following the experiment the electromygraphic (EMG) activity of different muscles, cardio-respiratory data, changes in total hemoglobin, tissue oxygenation and oscillatory movement of m. vastus lateralis, blood lactate and perceptual data of 12 highly trained alpine skiers were recorded. Maximal isometric knee extension and flexion strength, balance, and jumping performance were assessed before and after the experiment.
The knee angle (-10[degree sign]) and oscillatory movement (-20-25.5%) were lower with compression (P < 0.05 in all cases). The EMG activities of the tibialis anterior (20.2-28.9%), gastrocnemius medialis (4.9-15.1%), rectus femoris (9.6-23.5%), and vastus medialis (13.1-13.7%) muscles were all elevated by compression (P < 0.05 in all cases). Total hemoglobin was maintained during the 3-min period of simulated skiing with 20 or 40 mmHg compression, but the tissue saturation index was lower (P < 0.05) than with no compression. No differences in respiratory parameters, heart rate or blood lactate concentration were observed with or maximal isometric knee extension and flexion strength, balance, and jumping performance following simulated skiing for 3 min in the downhill tuck position were the same as in the absence of compression.
These findings demonstrate that with leg compression, alpine skiers could maintain a deeper tuck position with less perceived exertion and greater deoxygenation of the vastus lateralis muscle, with no differences in whole-body oxygen consumption or blood lactate concentration. These changes occurred without compromising maximal leg strength, jumping performance or balance. Accordingly, our results indicate that the use of lower leg compression in the range of 20-40 mmHg may improve alpine skiing performance by allowing a deeper tuck position and lowering perceived exertion.
... Whether a knee brace is required after ACLR is a debatable topic [1,[14][15][16][17]. Rodríguez-Merchán et al. mentioned in his reviewed article that postoperative bracing after ACLR does not relieve pain and induce function and stability. ...
Background:
Due to the rapid spread of the coronavirus disease-19 (COVID-19), most of the patients expressed a reluctance to undergo postoperative rehabilitation at a rehabilitation clinic. Therefore, in this scenario it was necessary to reshape the crucial role of postoperative rehabilitation of these patients. We conducted a telerehabilitation program based on an artificial intelligence brace (AI brace) which can monitor the progress of rehabilitation through an app and an internet server. Our hypothesis was that home-based telerehabilitation might provide clinical outcomes comparable to face-to-face, hospital-based rehabilitation programs in terms of effectiveness.
Methods:
A retrospective cohort study enrolled patients who received anterior cruciate ligament reconstruction (ACLR) between January and September 2020. Patients were divided into two groups: the tele-AI group received telerehabilitation with an AI brace while the FTF group had face-to-face, hospital-based rehabilitation. Clinical knee functional scores and Tegner Activity Scale (TAS) were assessed and analyzed until 12 months after the operation.
Results:
The tele-AI group had higher IKDC scores at 3 months (p = 0.0443) and 6 months (p = 0.0052) after surgery and higher KOOS scores at 1 month (p = 0.0365) and 6 months (p = 0.0375) after surgery. However, no significant difference between the two groups was detected at the end of the follow-up. The tele-AI group had higher TAS than FTF group after 1 year.
Conclusions:
Telerehabilitation after ACLR seems to provide a superior short-term outcome compared to hospital-based rehabilitation during the COVID-19 pandemic.
... The rapid increase in compression sleeve (CS) use on the upper and lower extremities has been accompanied by an equally rapid increase in both theoretical and clinical research in the rehabilitation and medicine fields [1][2][3]. CS use improves sensorimotor performance, especially in terms of joint position sense (JPS) and motor steadiness [4,5]. CS can compensate for the impairments affecting JPS and improve steadiness when there is muscle fatigue [6,7]. ...
PurposeThe application of compression sleeve (CS) has rapidly developed in the medicine and rehabilitation fields and is commonly used for improving sensorimotor function. Despite a considerable amount of sensorimotor-related evidence and clinical outcomes analysis being available, little is known about the effects of CS-induced sensory afferent input on corticomuscular functional connectivity (corticomuscular coherence, CMC) and reaction time (RT). Therefore, the purpose of this study was to investigate the effect of wearing CS on CMC and sensorimotor performance.Methods
Fourteen healthy volunteers were enrolled in this study and randomly performed visual tracking motor task, RT test and joint position sense (JPS) test with and without CS (CS and non-CS conditions). Electroencephalography and electromyography of the wrist extensor during the visual tracking motor task were used to calculate CMC. Joint angle steadiness, joint position error, pre-motor time (PMT), electromechanical delay (EMD) time and RT were calculated to compare sensorimotor performance with and without CS.ResultsWhen wearing CS decreased CMC, shortened both PMT and RT compared to the non-CS condition (p < .05). The JPS and the steadiness of the wrist joint were improved when CS was worn (p < .05).Conclusion
Our findings indicated that wearing CS altered CMC and improved sensorimotor function.
... A postulation is that stimulation of the muscle spindles and mechanoreceptors along the shank, when wearing compression socks, enhances postural regulation by contortion and disturbances of haptic system receptors in the skin and soft tissue of the lower limbs [8]. Recent investigations have suggested some beneficial effects of wearing a knee compressive sleeve in reducing postural sway in the anteroposterior (AP) direction [15] and donning a compression stocking reduced the CoP trajectory amplitude [16]. In an elderly sample, Losa Iglesia (2012) [17] reported that wearing socks reduced sway areas compared to when the same participants regulated posture in a barefoot condition. ...
Background:
Stimulation of lower limbs' cutaneous receptors and mechanoreceptors through compression garments could potentially increase somatosensory system efficiency and aid postural regulation in elderly individuals.
Research question:
This study examined immediate effects of wearing knee length socks (KLS) of various compression levels on somatosensory function in community-dwelling healthy elderly men and women during a double-limb standing, balancing task.
Methods:
A total of forty-six elderly participants (Male = 23), aged between 65 and 84 years old, randomly selected from the Singapore community-dwelling, healthy population. Three treatment interventions (wearing clinical compression socks; wearing non-clinical compression socks; wearing commercial socks) and one control condition (barefoot), in a counterbalanced order, were administered to participants while they performed a 30-s Romberg test, with four levels of performance difficulty: (1) standing on a stable surface with vision (SO); (2) a stable surface without vision (SC); (3) a foam surface with vision (FO); and (4), a foam surface without vision (FC).
Results:
Results showed that immediate effects of applying KLS of various compression levels significantly reduced sway area, trace length, velocity, and anterior-posterior (AP) sway as compared to barefoot condition (control) during the FO task condition.
Significance:
This finding indicates the positive immediate effects of garments on somatosensory system function and postural regulation in the elderly men and women, especially when standing on the unstable surface. Wearing compression KLS could be included as a viable intervention on top of other forms of balance training to reduce risk of falling in elderly people.
... 6,7,15,22,23,25 Given the improved proprioception, it is plausible that patients who have suffered knee injuries could benefit from wearing compression garments to maximize their rehabilitation process. 21 Furthermore, these compression garments may be of maximal benefit to patients at risk of injuries due to poor mechanics and dynamic instability. Compression-induced stimulation of the cutaneous receptors at the knee joint has been shown to increase kinesthesia. ...
Background
The use of compression garments has spread rapidly among athletes, largely because of marketing and perceived benefits. Upon review, it is unclear whether compression garments have a significant effect on performance and recovery, although they have been found to enhance proprioception. Further, it is reported that compression of the knee joint improves both dynamic and static balance. However, there is currently a paucity of data demonstrating the effects of compression garments on the biomechanical risk factors of knee-related injuries in female athletes.
Purpose
To evaluate the ability of a directional compression garment to alter hip and knee kinematics and kinetics during a drop vertical jump (DVJ) in healthy college-aged female athletes.
Study Design
Controlled laboratory study.
Methods
A sample of 23 healthy female collegiate athletes (mean age, 19.6 ± 1.3 years) participating in jumping sports (volleyball, basketball, and soccer) was included in this analysis. Each athlete performed 2 sets of 3 DVJs with and without a directional compression garment. Three-dimensional hip and knee kinematics and kinetics were collected using a standard Helen-Hayes 29-marker set, which was removed and reapplied after the garment was fitted, as well as 8 visible-red cameras and 2 force platforms. Each participant was tested in a single session.
Results
Hip abduction range of motion was significantly reduced from 12.6° ± 5.5° to 10.2° ± 4.6° (P = .002) while performing DVJs without and with the compression garment, respectively. No statistically significant differences between conditions were found in peak hip abduction, knee valgus range of motion, peak valgus, peak hip abduction moment, and peak knee valgus moment.
Conclusion
The results of this study show that wearing compression garments does have minimal effects on lower body mechanics during landing from a DVJ, partially supporting the idea that compression garments could acutely alter movement patterns associated with the knee injury risk. However, further research should focus on muscle activation patterns and adaptations over time.
Clinical Relevance
The use of specifically designed compression garments could aid in the prevention of knee injuries by inducing changes in jumping mechanics.
... In fact, athletes with better sport performance have been shown to display better balance. 2 Poor balance as measured by an increase in postural sway is generally associated with an increased risk of lower limb injury risk. 3,4 Although the ankle plays the central role in controlling balance during upright standing, 5 the knee plays an important role in one-legged balance control in the antero-The Effect of Three Knee Brace Styles on Balance Ability posterior direction, as demonstrated by Kuster et al. 6 Knee braces are widely used in sport to prevent injuries (prophylactic knee braces) or to return to activity after injury (functional knee braces). Knee braces might improve balance ability with both a mechanical stabilization and an improvement in proprioception. ...
Knee braces might enhance balance ability by improving joint stabilization or proprioception. We tested the effects of three different knee braces on single-limb balance. There was a significant decrease in the anteroposterior balance ability when participants wore the brace that was described as the most cumbersome or uncomfortable (p =.04). For the other two braces, there was no difference in single-limb balance ability compared with the no brace condition. Comfort and weight of the knee brace might alter somatosensory inputs, which play an important role in balance ability.
... Thus, despite the previous studies which stated that sports equipment with a particular compression could improve strength output, the possible mechanism -such as the compression effect -may change the kinematics parameters in motion or else increase muscle proprioception and balance [27,28] still needs to be confirmed. ...
The utilization of sport-related compression garments has attracted a great deal of attention from among Sports Science scholars. The function of the garments, such as to maintain muscle functions, reduce sports injuries and improve athletic performance, has been an issue of debate since the beginning of the new century. In this study, a number of methods including a literature review, logical analysis and mathematical statistics, are used to analyse earlier compression garments research, which can be found by searching hardcopy journals and online databases. Among the existing studies, most have tested and confirmed the functions of the garments; however, only a few have mentioned the underlying mechanism. Thus, by using more advanced and appropriate compression materials, future studies into compression garments will be focused on the vibration characteristics of muscles (soft tissues), and especially on their proprioceptive sensation, neuromuscular control, injury prevention and performance enhancement.
... This is probably due to the fact that knee joint position sense increased with strapping. On the basis of the reduced EMG of antagonists (TA and BF), muscle coordination was possibly optimized with strapping on metatarsals, which is in agreement with the effect of compression sleeve on the knee (Kuster, Grob, Kuster, Wood, & Gächter, 1999). ...
... Mechanoreceptors in the muscle tissue, skin, ligaments and joint capsules provide continuous feedback concerning the movement of these segments [62]. Both compression garment and sports taping have been reported to stimulate these mechanoreceptors, thereby elevating the input to neuromuscular pathways, reflex activation, and sensory feedback [18,19,[63][64][65] and improving proprioception [66,67] and power production [15,16]. Taping alters the electromyographic activity of the quadriceps femoris muscle by enhancing the rate of firing and/or recruitment of motor units [15]. ...
Background
Repeated sprint performance is determined by explosive production of power, as well as rapid recovery between successive sprints, and there is evidence that compression garments and sports taping can improve both of these factors.
Methods
In each of two sub-studies, female athletes performed two sets of 30 30-m sprints (one sprint per minute), one set wearing compression garment with adhesive silicone stripes (CGSS) intended to mimic taping and the other with normal clothing, in randomized order. Sub-study 1 (n = 12) focused on cardio-respiratory, metabolic, hemodynamic and perceptual responses, while neuronal and biomechanical parameters were examined in sub-study 2 (n = 12).
Results
In both sub-studies the CGSS improved repeated sprint performance during the final 10 sprints (best P < 0.01, d = 0.61). None of the cardio-respiratory or metabolic variables monitored were altered by wearing this garment (best P = 0.06, d = 0.71). Also during the final 10 sprints, rating of perceived exertion by the upper leg muscles was reduced (P = 0.01, d = 1.1), step length increased (P = 0.01, d = 0.91) and activation of the m. rectus femoris elevated (P = 0.01, d = 1.24), while the hip flexion angle was lowered throughout the protocol (best P < 0.01, d = 2.28) and step frequency (best P = 0.34, d = 0.2) remained unaltered.
Conclusion
Although the physiological parameters monitored were unchanged, the CGSS appears to improve performance during 30 30-m repeated sprints by reducing perceived exertion and altering running technique.
... 82 Because of the decreased threshold for movement detection, muscle recruitment would hypothetically be better integrated and prevent excessive body sway. 83 Wu et al 84 compared functional knee bracing to placebo knee bracing and controls in patients who had undergone ACL reconstruction. Proprioception was increased similarly between both braced groups with no significant differences across subjective and objective outcomes. ...
Ligamentous knee injuries are common and costly, both in financial terms and time missed from work and recreational activities. Furthermore, ligamentous injuries appear to predispose patients to future osteoarthritis and other morbidities. Therefore, prevention strategies are important in limiting the potential impact of these injuries. Knee braces are one of the most often prescribed devices in the billion-dollar orthotic industry. Despite widespread use of prophylactic and functional knee braces, the evidence supporting their efficacy in reducing and/or preventing injury remains limited. Knee braces have been shown to be more effective in preventing medial collateral ligament injuries than anterior cruciate ligament injuries in both cadaveric and clinical studies. The use of functional braces after anterior cruciate ligament reconstruction has been supported and refuted in both postoperative and long-term studies.
... Pour Risberg et al. [75] et Beynon et al. [20], l'orthèse n'améliore pas la proprioception : ils ne retrouvaient pas de différence de seuil de détection d'une flexion passive avec ou sans orthèse tant pour des genoux sains que des genoux opérés après rupture du LCAE et suivis en moyenne deux ans après opération. En revanche, Kuster [57] observait avec une genouillère souple, à un an d'une reconstruction du LCAE, une amélioration de la coordination musculaire, et la restauration plus rapide de l'équilibre après un saut sur une plate forme de force, impliquant la fonction d'équilibration et une participation psychologique. Barrett [14] a montré qu'une contention élastique au même titre qu'une genouillère articulée améliorait le sens de position articulaire. ...
Objective. – To review the literature for the benefits of the three different knee braces (prophylactic, rehabilitation, functional) that can be used to treat ligament injuries of the knee. What is their influence on stability? Do they have adverse effects? Is their use justified?Methods. – We searched the Medline and Embase databases with use of the keywords knee, orthoses, brace, proprioception, stability, rehabilitation, physical therapy, and anterior cruciate ligament for reports published between 1980 and 2003 and selected 93 articles, expert reports or literature reviews.Results. – Anterior tibial displacement can be controlled with mechanical strains (150 N), which are lower than physiological restraints? (400 N). The control of joint position is improved by increasing proprioception. Soft tissue stiffness influences the control of anterior tibial displacement. The beneficial effects observed are mainly subjective. Our analysis of the literature showed limitations and variations in study methodologies.Conclusion. – We did not find any justification for use of either prophylactic or rehabilitation braces. Functional braces can improve stability, as reported by the patient, and may be used in some situations.
... An additional mechanism contributing to the improved postural control may be an altered response of joint tactile receptors and mechanoreceptors. Several studies 16,17 have shown that application of a knee brace or sleeve improves postural control. The mechanism behind the increased postural steadiness has been attributed to the added somatosensory cues provided by the brace or sleeve. ...
Palmieri RM, Ingersoll CD, Cordova ML, Kinzey SJ, Stone MB, Krause BA. The effect of a simulated knee joint effusion on postural control in healthy subjects. Arch Phys Med Rehabil 2003;84:1076-9.
Background
Compression garments are regularly worn during exercise to improve physical performance, mitigate fatigue responses, and enhance recovery. However, evidence for their efficacy is varied and the methodological approaches and outcome measures used within the scientific literature are diverse.
Objectives
The aim of this scoping review is to provide a comprehensive overview of the effects of compression garments on commonly assessed outcome measures in response to exercise, including: performance, biomechanical, neuromuscular, cardiovascular, cardiorespiratory, muscle damage, thermoregulatory, and perceptual responses.
Methods
A systematic search of electronic databases (PubMed, SPORTDiscus, Web of Science and CINAHL Complete) was performed from the earliest record to 27 December, 2020.
Results
In total, 183 studies were identified for qualitative analysis with the following breakdown: performance and muscle function outcomes: 115 studies (63%), biomechanical and neuromuscular: 59 (32%), blood and saliva markers: 85 (46%), cardiovascular: 76 (42%), cardiorespiratory: 39 (21%), thermoregulatory: 19 (10%) and perceptual: 98 (54%). Approximately 85% ( n = 156) of studies were published between 2010 and 2020.
Conclusions
Evidence is equivocal as to whether garments improve physical performance, with little evidence supporting improvements in kinetic or kinematic outcomes. Compression likely reduces muscle oscillatory properties and has a positive effect on sensorimotor systems. Findings suggest potential increases in arterial blood flow; however, it is unlikely that compression garments meaningfully change metabolic responses, blood pressure, heart rate, and cardiorespiratory measures. Compression garments increase localised skin temperature and may reduce perceptions of muscle soreness and pain following exercise; however, rating of perceived exertion during exercise is likely unchanged. It is unlikely that compression garments negatively influence exercise-related outcomes. Future research should assess wearer belief in compression garments, report pressure ranges at multiple sites as well as garment material, and finally examine individual responses and varying compression coverage areas.
Knee braces continue to be a widely utilized piece of medical equipment, ranging from simple over the counter sleeves to more complex functional braces, with the ability to provide electrical stimulation to muscle groups. Despite their popularity, alternatives to knee braces exist for patients who find braces to be ineffective, uncomfortable, cumbersome, or overly expensive. While high-quality studies are lacking for modalities such as neoprene sleeves, compression stockings, and kinesiotaping, there is promising evidence that these interventions can confer an element of stability and pain relief for a variety of knee pathologies both with regard to acute and chronic injuries as well as in the postoperative rehabilitation period. While no “holy grail” exists for the ideal brace, or bracing alternative, it is important for providers to be aware of the options available to patients as well as the current evidence for these various modalities, so that the provider can best guide musculoskeletal care.
Purpose
Our primary objectives were to (1) describe current approaches for kinetic measurements in individuals following anterior cruciate ligament reconstruction (ACLR) and (2) suggest considerations for methodological reporting. Secondarily, we explored the relationship between kinetic measurement system findings and patient-reported outcome measures (PROMs).
Methods
We followed the PRISMA extension for scoping reviews and Arksey and O’Malley’s 6-stage framework. Seven electronic databases were systematically searched from inception to June 2020. Original research papers reporting parameters measured by kinetic measurement systems in individuals at least 6-months post primary ACLR were included.
Results
In 158 included studies, 7 kinetic measurement systems (force plates, balance platforms, pressure mats, force-measuring treadmills, Wii balance boards, contact mats connected to jump systems, and single-sensor insoles) were identified 4 main movement categories (landing/jumping, standing balance, gait, and other functional tasks). Substantial heterogeneity was noted in the methods used and outcomes assessed; this review highlighted common methodological reporting gaps for essential items related to movement tasks, kinetic system features, justification and operationalization of selected outcome parameters, participant preparation, and testing protocol details. Accordingly, we suggest considerations for methodological reporting in future research. Only 6 studies included PROMs with inconsistency in the reported parameters and/or PROMs.
Conclusion
Clear and accurate reporting is vital to facilitate cross-study comparisons and improve the clinical application of kinetic measurement systems after ACLR. Based on the current evidence, we suggest methodological considerations to guide reporting in future research. Future studies are needed to examine potential correlations between kinetic parameters and PROMs.
Injuries to various structures of the knee joint, including the ligaments, menisci, and patellofemoral components, compose a significant portion of sports-related injuries seen by health care providers and compromise a patient's knee joint function and stability. Knee orthoses have been used in each step of the sport performance process, such as injury minimization, ligament rehabilitation after reconstruction, and treatment of functional instability of the knee joint. The knee joint allows for flexion and extension with some degree of translation and axial rotation. Shear forces act upon the knee during gait and in weight-bearing tasks. Proper functioning of knee braces must take into account these biomechanical factors. Both prefabricated (“off-the-shelf”) and custom-made knee brace designs have proven effective, and each has benefits with cost, fit, weight, and material components. More recently, braces have been manufactured with composite lightweight materials, such as carbon fiber and aluminum. Athletes have used knee orthoses both to prevent medial collateral ligament (MCL) and anterior cruciate ligament (ACL) injury and to protect ACL-deficient knees or an ACL-reconstructed graft while returning to full activity. Knee braces have become an important component in functional rehabilitation programs for treatment of MCL sprains. Acute grade I and II posterior cruciate ligament (PCL) tears have been shown to heal with bracing, protected weight bearing, and quadriceps muscle rehabilitation. Braces are now used in osteoarthritis to enhance function and reduce pain.
This study investigated the acute effects of compression garments (CG) on balance control in elite athletes. 15 male professional handball players were recruited. They had to stand as motionless as possible in a monopedal stance on a force plate with the eyes closed and on a wobble board with the eyes open, while wearing CG or not. Centre of foot pressure mean velocity and surface area were calculated. Statistics were first calculated with the data from the whole sample. A hierarchical cluster analysis was also performed in order to categorize the participants' behaviours into subgroups with similar characteristics. The whole group analysis showed that there were no significant effects attributed to CG. The clustering analysis identified two distinct and homogeneous subgroups of participants. Only athletes with the best balance abilities at baseline could benefit from CG wearing to improve their balance control. These athletes, who swayed less and were more sensitive to somatosensory manipulation due to CG wearing, seem to control balance by adopting a support-dependent preferred sensorimotor tactic. Our findings suggest that amongst high-level athletes, the ability to benefit from CG wearing to improve balance control seems to depend on participants' intrinsic balance skills and/or preferred sensorimotor tactics. Full text: https://rdcu.be/b7ote
Objective
To investigate the effects of compression shorts on pain and performance in football players with groin pain.
Study design
Double blinded randomized controlled trial.
Setting
Soccer pitch.
Participants
Thirty-four male football players with groin pain.
Main outcome measures
The effect of wearing zoned high compression shorts (ZHC-shorts), non-zoned low compression shorts (NZLC-shorts), and normal sports clothes on pain measured with the Numeric Pain Rating Scale (NPRS) and performance during the Copenhagen 5-s squeeze test (CS), the Illinois Agility test (IAT), and maximum shooting (ST). The effects of wearing ZHC versus NZLC shorts on symptoms were measured using the Hip and groin outcome score (HAGOS) during actual football activities.
Results
Wearing ZHC-shorts reduced pain during the IAT (1.4, ES = 0.58, p= <0.01) and ST (1.2, ES = 0.47, p= <0.01) compared to wearing normal sports clothes, but did not negatively affect performance. Compared to the baseline HAGOS scores a clinically significant improvement in the symptoms (9.7, ES = 0.63, p= <0.01) and sport/recreation (13.2, ES = 0.68, p = 0.01) subscales was found when wearing the ZHC-short during football activities.
Conclusion
Wearing zoned high compression shorts could be useful in reducing groin pain in football players during their football activities.
The purpose of this study was to investigate the effects of functional wear which compression clothing developed having supplementary lines of differing stretch ability (below, FW), specifically in terms of posture control at one leg landing in comparison with simple compression wear (below, CW). Subjects were 22 healthy male and female university students, motion task was the drop Jump landing from 30 cm height. As for the knee joint alignment on the frontal plane, FW was varus position although CW was valgus and neutral position at 40msec and 80msec after landing. As for knee joint moment on the frontal plane, FW showed the varus moment while CW showed the valgus moment at 40msec after landing. While at 80msec after landing, the valgus moment of FW was significantly smaller than that of CW. As a result, FW controlled knee joint valgus alignment and reduced the knee joint valgus moment that could be risk factor of ACL injury. It was thus suggested that FW could contribute to the prevention ACL injury and reoccurrence.
The rehabilitation process begins immediately after injury to the anterior cruciate ligament (ACL). The goal of preoperative rehabilitation is to prepare the patient for surgery. Current rehabilitation programs focus on strengthening exercises and proprioceptive and neuromuscular control drills to provide a neurologic stimulus. It is also important to address preexisting factors, especially for the female athlete, that may predispose to future injury, such as hip and hamstring weakness. Our goal in the rehabilitation program is to restore full, unrestricted function and to assist the patient to return to 100% of the preinjury level while achieving excellent long-term outcomes.
Although some articles in the literature are in favor of the use of a postoperative brace after anterior cruciate ligament (ACL) reconstruction, this review found that several systematic reviews and other reports on the topic do not support the use of a postoperative brace after ACL reconstruction. There is no scientific evidence so far to support the routine use of a functional knee brace following a successful ACL reconstruction in the postoperative course. Most authors believe that bracing is not necessary. There is insufficient evidence to inform current practice. Good-quality randomized trials are required to remedy this situation. Future studies should better define the role of a brace following ACL surgery. A search of MEDLINE for articles published between January 1, 1995, and September 30, 2013, was performed. Key search terms used were ACL reconstruction and knee brace. Ninety-one articles were found, but only 28 focused on the subject of bracing after ACL reconstruction and were selected for this review. Several systematic reviews and randomized, controlled trials on the topic do not recommend the use of postoperative brace after ACL reconstruction. Postoperative bracing after ACL reconstruction does not seem to help with pain, function, rehabilitation, and stability. The literature does not support the use of a postoperative brace following ACL reconstruction. [Orthopedics.].
Rehabilitation associated with anterior cruciate ligament injury continues to evolve, with the current emphasis on immediate weight bearing and range of motion, coupled with progressive muscular strengthening, proprioception, dynamic stability, and neuromuscular control exercises. The preoperative phase of the rehabilitation program is critical to ensure proper preparation of the patient for surgery, facilitating a successful postoperative outcome. The primary goal is to return the patient's knee as close as possible to homeostasis by reducing swelling and pain, restoring range of motion, and re-establishing quadriceps control following injury and before surgery The purpose of this article is to provide the reader with a thorough scientifically based preoperative rehabilitation program that can be successfully implemented in any patient before undergoing anterior cruciate ligament reconstruction.
[Purpose] The aim of this study was to determine the functional level of activity and postural control after rehabilitation of anterior cruciate ligament reconstructed knees and compare them with non-operated limbs and healthy limbs in control subjects. [Subjects] Twenty-seven patients participated in the study: 17 had undergone reconstruction with a bone-patellar tendon-bone and 10 with a semitendinosus graft technique. The same rehabilitation protocol was used for all of the patients. Besides the patients, 18 healthy volunteers participated as a control group. [Methods] Both groups were tested for one-leg standing (eyes open and closed), static (eyes open and closed) and dynamic postural control on The Kinesthetic Ability Trainer-KAT 2000 (OWM Medical, Carlsbad, California, USA) at the 3, 6 and 12 month post-operation. Functional outcomes of the rehabilitation were evaluated by Lysholm scoring. [Results] There were no significant differences for the eyes open static stabilometry test between operated and non-operated limbs of the patients. On the other hand, there were statistically significant differences for the closed eyes static balance test between the operated and non-operated limbs at 3 and 6 months after surgery. There were significant differences for the eyes open static balance test between the 3rd and 6th, and 6th and 12th months and for the eyes closed test of non-operated limbs between the same months as well. No statistically significant differences were noted in the dynamic balance tests between the patients and the control group. Lysholm scores of the patients obtained at 6 and 12th months after surgery were significantly better than those at 3 months after surgery. Different operation techniques revealed no significant differences in any test performed at any time. [Conclusions] Performing a postoperative sportive rehabilitation including specific proprioceptive training sessions has positive effects both on clinical status and postural control of the patients.
INTRODUCTION: The aim of this work was to proceed to a literature review to determine the physiological justifications underlying knee orthosis use in medical practice.METHOD: An analysis of the international literature relating to the years 1980-2000 was carried out with the Medline data bank. We added extra articles focusing on the validity of the protocols used in the different evaluations.RESULTS: Five hundred and twelve articles were selected and 46 articles of experimental validation were retained. The experimental protocols are divided into in vitro studies and clinical studies carried out in both healthy subject and patients. Only the in vitro experimental data allowed to reach strain values simulating traumatisms of the articular structures. They allowed to define the interest and limits of the orthosis according to articular physiology. Measurements carried out in vivo were effective to characterize the parameters of stability and proprioception and to disriminate between the orthosis. These studies correspond to experimental situations with related constraints that remain far below lesional constraints, focusing on their clinical validity.CONCLUSION: This work point out many studies focusing on the physiological characterization of the knee orthosis. This evaluation of the orthosis through a single methodology remains difficult and justifies confrontation with clinical trials data.
In this paper a multi-spots temperature monitoring and alarming system based on a person computer is designed. The system consists of a person computer as a host and a subsystem as a slave. The host can communicate with the slave by its serial port. The host can also control the slave and receive temperature value from it that can be displayed on the screen of the host. The host will alarm when the temperature value is beyond the user-defined two's complement alarm trigger values. The user program of the host is developed by Visual c++ 6.0. The slave consists of a microcontroller unit AT89S52, temperature sensors DS18B20, serial port electrical level converting circuit, alarm circuit, display circuit, power circuit and so on. The slave can receive temperature data from the sensors that can be displayed on its display and be sent to the host. The slave will also alarm when the temperature value is beyond the user-defined two's complement alarm trigger values. The system is simple, its cost is low and its operation is easy. Its accuracy and resolution is excellent. Keywords-person computer; DS18B20; microcontroller unit; serial communication
To assess original research addressing the effect of the application of compression clothing on sport performance and recovery after exercise, a computer-based literature research was performed in July 2011 using the electronic databases PubMed, MEDLINE, SPORTDiscus, and Web of Science. Studies examining the effect of compression clothing on endurance, strength and power, motor control, and physiological, psychological, and biomechanical parameters during or after exercise were included, and means and measures of variability of the outcome measures were recorded to estimate the effect size (Hedges g) and associated 95% confidence intervals for comparisons of experimental (compression) and control trials (noncompression). The characteristics of the compression clothing, participants, and study design were also extracted. The original research from peer-reviewed journals was examined using the Physiotherapy Evidence Database (PEDro) Scale. Results indicated small effect sizes for the application of compression clothing during exercise for short-duration sprints (10-60 m), vertical-jump height, extending time to exhaustion (such as running at VO2max or during incremental tests), and time-trial performance (3-60 min). When compression clothing was applied for recovery purposes after exercise, small to moderate effect sizes were observed in recovery of maximal strength and power, especially vertical-jump exercise; reductions in muscle swelling and perceived muscle pain; blood lactate removal; and increases in body temperature. These results suggest that the application of compression clothing may assist athletic performance and recovery in given situations with consideration of the effects magnitude and practical relevance.
We measured joint position sense in the knee by a new method which tests the proprioceptive contribution of the joint capsule and ligaments. The leg was supported on a splint, and held in several positions of flexion. The subjects' perception of the position was recorded on a visual analogue model and compared with the actual angle of flexion. Eighty-one normal and 45 osteoarthritic knees were examined, as were 10 knees with semi-constrained and 11 with hinged joint replacements. All were assessed with and without an elastic bandage around the knee. There was a steady decline in joint position sense with age in subjects with normal knees. Those with osteoarthritic knees had impaired joint position sense at all ages (p less than 0.001). Knee replacement improved the joint position sense slightly (p less than 0.02); semi-constrained replacement had a greater effect than hinged replacement. The effect of an elastic bandage in subjects with poor position sense was dramatic, improving accuracy by 40% (p less than 0.001). It is proposed that reduced proprioception in elderly and osteoarthritic subjects may be responsible for initiation or advancement of degeneration of the knee.
We have studied manual motor function in a man deafferented by a severe peripheral sensory neuropathy. Motor power was almost unaffected. Our patient could produce a very wide range of preprogrammed finger movements with remarkable accuracy, involving complex muscle synergies of the hand and forearm muscles. He could perform individual finger movements and outline figures in the air with his eyes closed. He had normal pre- and postmovement EEG potentials, and showed the normal bi/triphasic pattern of muscle activation in agonist and antagonist muscles during fast limb movements. He could also move his thumb accurately through three different distances at three different speeds, and could produce three different levels of force at his thumb pad when required. Although he could not judge the weights of objects placed in his hands without vision, he was able to match forces applied by the experimenter to the pad of each thumb if he was given a minimal indication of thumb movement.
Despite his success with these laboratory tasks, his hands were relatively useless to him in daily life. He was unable to grasp a pen and write, to fasten his shirt buttons or to hold a cup in one hand. Part of his difficulty lay in the absence of any automatic reflex correction in his voluntary movements, and also to an inability to sustain constant levels of muscle contraction without visual feedback over periods of more than one or two seconds. He was also unable to maintain long sequences of simple motor programmes without vision.
There are various methods of measuring proprioception at the knee. Beard et al (1993) have described a delay in reflex hamstring contraction in anterior cruciate deficient knees. We have repeated their experiment and were unable to detect any significant difference in reflex hamstring contraction between the injured and uninjured legs. We discuss possible neurophysiological and biomechanical causes for the conflicting results and conclude that this method may not be a valid measure of proprioception.
1. We analyzed the performance of a simple pantomimed gesture in 2 patients with large-fiber sensory neuropathy and 11 control subjects to determine how proprioceptive deafferentation disrupts unconstrained multijoint movements. Both patients had near-total loss of joint position, vibration, and discriminative touch sensation in the upper extremities. Muscle strength remained intact. 2. Subjects performed a gesture similar to slicing a loaf of bread. In this gesture, the hand first moves outward from the body, reverses direction sharply, and then moves back toward the body. Accurate performance requires precise coordination between the shoulder and elbow joints during movement reversals. Movements were performed under two conditions: with eyes open and with eyes closed. Three dimensional shoulder, elbow, wrist, and hand trajectories were recorded on a WATSMART system. 3. When control subjects performed the gesture with their eyes closed, their wrist trajectories were relatively straight and individual cycles of motion were planar. Movements reversed direction sharply, such that outward and inward portions of the wrist path were closely aligned. Corresponding to this spatial profile, the reversals in movement direction at the shoulder joint, from flexion to extension, and at the elbow joint, from extension to flexion, were synchronous. 4. In contrast, when deafferented patients performed the gesture with their eyes closed, their wrist trajectories were highly curved and individual cycles were severely nonplanar. The wrist paths showed a characteristic anomaly during the reversal in movement direction, when elbow joint movement became transiently locked. Correspondingly, the movement reversals at the shoulder and elbow joints were severely temporally decoupled. 5. When patients were able to view their limbs during performance of this gesture there was significant improvement in the linearity and planarity of movements. However, the patients remained unable to synchronize the movements at the shoulder and elbow joints to produce spatially precise wrist paths. 6. We conclude that loss of proprioception disrupts interjoint coordination and discuss the hypothesis that this interjoint coordination deficit results from a failure to control the interaction forces that arise between limb segments during multijoint movements.
The routine use of functional knee braces in the anterior cruciate ligament-deficient, injured, or reconstructed knee, lacks biomechanical support. Although subjective reports favoring bracing are plentiful, objective proof of significant control of tibial translation is not. This in vivo study was designed to assess the effect of six popular braces on anterior tibial translation, isokinetic performance, and neuromuscular function in five chronically unstable anterior cruciate ligament-deficient knees. A knee stress test was performed on a specially designed device that allowed free tibial movement while monitoring anterior tibial translation and muscle function in the quadriceps, hamstring, and gastrocnemius muscles. Results show that braces can decrease anterior tibial translation between 28.8% and 39.1% without the stabilizing contractions of the hamstring, quadriceps, and gastrocnemius muscles. With lower extremity muscle activation and bracing, anterior tibial translation was decreased between 69.8% and 84.9%. Some improvement in spinal level muscle reaction times was seen with brace use, especially in the quadriceps muscle. Unfortunately, most braces appear to consistently slow hamstring muscle reaction times at the voluntary level.
This investigation sought to identify neuromechanical mechanisms by which a subject with an anterior cruciate ligament (ACL)-deficient knee might cope with the potentially destabilizing joint stresses during both level and downhill walking. Kinematic, kinetic and electromyographic data were collected from 21 subjects with arthroscopically verified ACL-deficient knees and Lysholm scores of 55–100 ( ), as well as from 12 healthy control subjects. Electromyographic data were recorded from the skin surface overlying rectus femoris, biceps femoris and gastrocnemius muscles. A dismountable slope of 6 m length and a gradient of 19% was constructed for downhill walking. Sagittal plane net joint moments and muscle mechanical power at the knee joint were calculated from force platform and videographic records using the inverse dynamics approach. During level walking there were no kinematic nor kinetic differences seen between ACL-deficient subjects and normals. The typical profile of muscle power at the knee contained three peaks during stance: an eccentric peak during early stance (K1); a concentric peak at mid stance (K2); and a second smaller eccentric peak (K3) during late stance. During downhill walking ACL-deficient subjects displayed a significantly smaller K1 compared to normals and their K1:K3 ratio was significantly less than that of normal subjects. Whereas normal subjects showed no hamstring activity during stance in level walking there was continuous activity throughout the stance phase displayed by the ACL-deficient and normal subjects. During downhill walking both the ACL-deficient and normal subjects showed continuous hamstring activity. However, the ACL-deficient subjects showed a significant delay in peak hamstring activity during late swing. Both groups on average displayed gastrocnemius peak activity just on heel strike during downhill walking but the linear envelopes of the ACL-deficient subjects were much more tightly time-locked to this critical event.
1. Motor memory and the sense of effort have been investigated in a man with a complete large fibre sensory neuropathy for over 16 years. The perceptions of pain, heat, cold and muscular fatigue remained but he was without perceptions of light touch and proprioception below the neck. 2. The subject was able to discriminate weights held in the hand with an accuracy only slightly worse than control subjects (20 g in 200 g) when forearm movement and visual inspection were allowed. With eyes shut however he could only distinguish a weight of 200 g from 400 g. It is concluded that a crude sense of effort remains which may have a peripheral origin. 3. A limited motor memory was also present, which allowed him to maintain a posture or continue a simple repetitive movement. No novel movement was possible without visual feedback. 4. Differences in movement ability between this subject and others with similar if less pure sensory neuropathies are ascribed to rehabilitation.
Proprioception was measured in the knees of 20 subjects with instability of the anterior cruciate ligament and compared with 17 age-matched control subjects. There was diminished position sense and threshold for movement detection in the injured patients compared with the control group. The proprioceptive deficit recorded from the injured knee showed a significant correlation with the hamstring/quadriceps power ratio recorded from the injured leg.
Postural steadiness in one-legged stance has potential for evaluation of unilateral injuries and disorders, but any test protocol must be demonstrated to be both feasible and reliable. A testing protocol for using a force platform to measure steadiness in one-legged stance with eyes opened and eyes closed was successfully developed, and its within-session retest reliability was investigated in a group of 24 young, healthy subjects. Strategies were used to minimize the loss of data for trials in which the subjects incurred significant loss of balance from the one-legged position. The performance scores examined were the standard deviation of the three orthogonal force components and the two horizontal center of pressure (CP) coordinates averaged over four consecutive five-second trials. The retest coefficients for all test conditions were substantially improved compared with testing protocols reported earlier. Retest reliability was higher for performance scores based on force measures than for performance scores based on CP measures. The difference was statistically significant in two of the stances, with a similar trend in the other two stances. Further, factor analysis showed that force measures were the best predictors of steadiness in one-legged stance. Analysis of variance failed to detect any systematic effect for leg preference or laterality on steadiness in one-legged stance with eyes opened or eyes closed in the healthy subjects with no history of injury (p greater than .05). The test protocol described enables the development of clinical or experimental trials with repeated-measures design using the subject's nonaffected leg as a control.
We have assessed 45 patients who had undergone anterior cruciate reconstruction by a modified MacIntosh-Jones method. The results, using standard knee scores and clinical ligament testing, correlated poorly with the patient's own opinion and with the functional result. However, measurement of proprioception in the knee correlated well with both function (r = 0.84) and with patient satisfaction (r = 0.9). This study indicates that proprioception, rather than the clinical excellence of the repair, is a major factor in the outcome of anterior cruciate ligament reconstruction.
Eighteen male patients who had untreated chronic ACL rupture were studied in order to evaluate thigh muscle size, morphology, and isokinetic performance of the quadriceps muscle. Computed tomography disclosed a 5.1% mean atrophy of the quadriceps (P less than 0.05), 2.1% slight hypertrophy of the hamstrings (P less than 0.05), and also nonsignificant changes of all other muscle areas of the injured thigh. Muscle morphology (m. vastus lateralis) was normal in 11 biopsy specimens, whereas minor abnormalities (irregular shape or hypotrophy) could be seen in the rest. Isokinetic mechanical output of the knee extensors was 71% to 87% of that of the noninjured limb (P less than 0.01), and the mechanical output corrected for differences in quadriceps cross-sectional area was significantly lower in the injured than the uninjured limb. As there were no significant correlations between isokinetic performance and muscle size or qualitative morphology or morphometric data, the strength decrease cannot be explained by muscle atrophy or structural changes per se. We conclude that nonoptimal activation of the muscles during voluntary contractions is probably the most important causative mechanism of the strength decrease found in patients who have chronic symptomatic ACL tear.
The reliability and validity of force platform measures used to evaluate steadiness of stance were investigated in a group of 28 healthy subjects in four basic stance positions: two-legged, step, tandem, and one-legged stance. In each stance position five indices of steadiness were obtained by sampling the three orthogonal force signals and the two horizontal center of pressure (CP) signals for 15 seconds and computing the standard deviation for each signal. Correlations between these five indices derived from the force platform showed that the relationship between force and CP measures was generally weak. In fact, approximately 40% of the correlations were nonsignificant (p greater than .05). There was a strong trend for the retest reliability of force measures to be higher than the retest reliability of CP measures. The difference was statistically significant in three stances (p less than .05). Force measures were more sensitive than CP measures in discriminating the changes in steadiness which resulted from alterations to the base of support in the four stance positions. Factor analysis showed that force measures were the best predictors of steadiness in each stance, but the axis varied according to the particular stance condition. Although it may be appropriate in some cases to justify the choice of measure according to the nature of the clinical condition being studied, these results provide a rationale for choosing force measures in preference to CP measures on the fundamental principles of reliability and validity.
The purpose of this research was to determine if bracing altered muscle firing amplitude, duration, or timing, creating improved dynamic stability. We hypothesized that a derotational knee brace improved the stability of an ACL deficient knee by augmenting limb proprioception, causing hamstring muscles to increase in activity and/or to contract earlier during a side-step cut. Ten subjects with documented unilateral isolated ACL deficient knees and five normal controls participated. A strap dominant brace (Lenox Hill, Lenox Hill Brace, Inc., Long Island City, NY) and a shell dominant brace (CTi, Innovation Sports, Irvine, CA) were selected for study. Using footswitches and dynamic EMG, we tested each subject during performance of a side-step cutting maneuver. Subjects completed 15 trials: 5 without bracing, 5 with the strap dominant brace, and 5 with the shell dominant brace. Normals cut 10 times each on their dominant limb. In swing phase, subjects had 38% more and 32% higher lateral hamstring EMG activity than normals; in stance phase, subjects had less quadriceps and gastrocnemius activity but more medial hamstring activity. When braced during stance phase, the ACL deficient legs demonstrated a further reduction of 18% in quadriceps total activity and 14% in peak activity compared to the unbraced situation. The hamstrings showed a concomitant decrease of 18% in total activity. No timing differences were noted between the braced and unbraced conditions during swing or stance phase.(ABSTRACT TRUNCATED AT 250 WORDS)
Stabilometry is a technique designed to register postural equilibrium control. This investigation used a computerized strain gauge force plate to measure sway movements in the frontal plane with the patient standing on one leg. Fifty-five young healthy individuals were studied as a reference group and to determine the reproducibility of the method. The clinical population consisted of 14 patients with unilateral injuries to the lateral ligaments of the ankle. These were measured, both with and without an ankle brace. The different parameters used to describe the body sway could well discriminate between the injured and the uninjured leg. When the brace was used the effect was obvious and none of the parameters showed any significant difference compared to the uninjured leg.
Proprioception was quantified in a group of patients who had documented complete ACL tears. Threshold to detection of passive change in position of the knee was measured using a well-described test. Eleven pa tients with arthroscopically proven complete ACL tears and findings consistent with moderate to severe anter olateral rotatory instability were tested. Testing was done within the 30° to 40° range of knee flexion. Patients were blindfolded and the injured and uninjured knees were tested in random sequence so that the normal knee could serve as an internal control. Testing was also done in a blind manner, i.e., the examiner did not know which knee had been injured. An age- matched control group underwent identical testing. Po tentially significant variables such as age, time from injury, and degree of rehabilitation as measured by thigh circumference and isokinetic testing of the knee were included in a multivariate analysis.
Control subjects demonstrated virtually identical threshold values between their two knees, the mean variation being less than 2%. The test group, however, showed a significantly higher mean threshold value for the injured versus the noninjured knee (P < 0.01), the mean variation being over 25%. Multivariate analysis demonstrated that changes recorded in the propriocep tion of the injured knee were attributable to the loss of the ACL rather than to other variables. Patients who have complete ACL tears and moderate to severe rotatory instability may also experience a decline in proprioceptive function of their knee.
Accelerated rehabilitation after anterior cruciate ligament (ACL) reconstruction has become increasingly popular. Methods employed include immediate extension of the knee and immediate full weight bearing despite the risks presented by a graft pull-out fixation strength of 200-500 N. The purpose of this study was to calculate the tibiofemoral shear forces and the dynamic stabilising factors at the knee joint for the reasonably demanding task of downhill walking, in order to determine whether or not this task presented a postoperative risk to the patient. Kinematic and kinetic data were collected on six male and six female healthy subjects during downhill walking on a ramp with a 19% gradient. Planar net joint moments and mechanical power at the knee joint were calculated for the sagittal view using a force platform and videographic records together with standard inverse dynamics procedures. A two-dimensional knee joint model was then utilised to calculate the tibiofemoral shear and compressive forces, based on the predictions of joint reaction force and net moment at the knee. Linear envelopes of the electromyographic (EMG) activity recorded from the rectus femoris, gastrocnemius and biceps femoris muscles were also obtained. The maximum tibiofemoral shear force occurred at 20% of stance phase and was, on average, 1.2 times body weight (BW) for male subjects and 1.7 times BW for female subjects. The tibiofemoral compressive force was 7 times BW for males and 8.5 times BW for females during downhill walking. The hamstring muscle showed almost continuous activity throughout the whole of the stance phase.(ABSTRACT TRUNCATED AT 250 WORDS)
Ankle supports are commonly used in an attempt to decrease the risk of ankle injury during sport. However, their use may also impair postural control, which is an integral component of sports participation. The aim of this study was to investigate the effects of three different ankle supports (tape, brace, and elastic bandage) on postural control in 24 normal subjects with a mean age of 24.8 years (+/- 4.4). Two measures were used to evaluate postural control in one-legged stance with the eyes closed: variability of mediolateral ground reaction force (acquired from a force platform) and frequency of foot touchdowns by the nonsupport leg (assumed to indicate ability of the subject to maintain one-legged stance posture). Both measures revealed a differential effect for ankle support on postural control. The use of an elastic bandage had no significant effect on postural control (p > 0.05), while the use of tape or a brace had a significant detrimental effect (p < 0.05). While wearing the tape or a brace, subjects were less steady and touched down more frequently. Restriction of ankle movement was offered as a possible explanation for the results, since postural control was impaired only by the ankle supports which limited ankle motion. These findings may have implications regarding impaired athletic performance.
1. Recent studies have shown that the CNS uses proprioceptive information to coordinate multijoint movement sequences; proprioceptive input related to the kinematics of one joint rotation in a movement sequence can be used to trigger a subsequent joint rotation. In this paper we adopt a broad definition of "proprioception," which includes all somatosensory information related to joint posture and kinematics. This paper addresses how the CNS uses proprioceptive information related to the velocity and position of joints to coordinate multijoint movement sequences. 2. Normal human subjects sat at an experimental apparatus and performed a movement sequence with the right arm without visual feedback. The apparatus passively rotated the right elbow horizontally in the extension direction with either a constant velocity trajectory or an unpredictable velocity trajectory. The subjects' task was to open briskly the right hand when the elbow passed through a prescribed target position, similar to backhand throwing in the horizontal plane. The randomization of elbow velocities and the absence of visual information was used to discourage subjects from using any information other than proprioceptive input to perform the task. 3. Our results indicate that the CNS is able to extract the necessary kinematic information from proprioceptive input to trigger the hand opening at the correct elbow position. We estimated the minimal sensory conduction and processing delay to be 150 ms, and on the basis of this estimate, we predicted the expected performance with different degrees of reduced proprioceptive information. These predictions were compared with the subjects' actual performances, revealing that the CNS was using proprioceptive input related to joint velocity in this motor task. To determine whether position information was also being used, we examined the subjects' performances with unpredictable velocity trajectories. The results from experiments with unpredictable velocity trajectories indicate that the CNS extracts proprioceptive information related to both the velocity and the angular position of the joint to trigger the hand movement in this movement sequence. 4. To determine the generality of proprioceptive triggering in movement sequences, we estimated the minimal movement duration with which proprioceptive information can be used as well as the amount of learning required to use proprioceptive input to perform the task. The temporal limits for proprioceptive processing in this movement task were established by determining the minimal movement time during which the task could be performed.(ABSTRACT TRUNCATED AT 400 WORDS)
Postural control was investigated following unilateral inversion injury of the ankle in 24 trained and 24 untrained subjects at least 8 weeks following injury and following resumption of high-speed activities. The two groups differed in the practice of balance exercises in one-legged stance during rehabilitation. Using a force platform the variability of the mediolateral force signal was used to quantify steadiness as each subject stood in one-legged stance with the eyes open and closed on the injured and noninjured legs. A three way analysis of variance showed that for the untrained subjects postural steadiness was significantly worse on the injured leg than the noninjured leg both with eyes open (p < .05) and closed (p < .05). No postural deficit was found on the injured leg of the trained subjects with eyes open or closed (p > .05). It is strongly recommended that rehabilitation following inversion injury of the ankle include balance retraining to minimize the risk of further injury.
We measured proprioception of the knee joint by an active and a passive method in 40 subjects under 30 years of age and in 80 subjects older than 50 years with no evidence of knee joint disease. Joint position sense was also determined in an additional 59 patients with osteoarthrosis of the knee. Proprioception was found to decline with increasing age. In the osteoarthritic knee the measured values were significantly higher than in both groups without knee-joint involvement. An elastic bandage had a positive effect. There was a positive correlation between proprioception and clinical parameters. Walking ability and range of motion did not significantly influence the proprioception. Patients receiving physical therapy showed an improved joint position sense.
A computer-based model of the knee was used to study forces in the cruciate ligaments induced by co-contraction of the extensor and flexor muscles, in the absence of external loads. Ligament forces are required whenever the components of the muscle forces parallel to the tibial plateau do not balance. When the extending effect of quadriceps exactly balances the flexing effect of hamstrings, the horizontal components of the two muscle forces also balance only at the critical flexion angle of 22 degrees. The calculations show that co-contraction of the quadriceps and hamstring muscles loads the anterior cruciate ligament from full extension to 22 degrees of flexion and loads the posterior cruciate at higher flexion angles. In these two regions of flexion, the forward pull of the patellar tendon on the tibia is, respectively, greater than or less than the backward pull of hamstrings. Simultaneous quadriceps and gastrocnemius contraction loads the anterior cruciate over the entire flexion range. Simultaneous contraction of all three muscle groups can unload the cruciate ligaments entirely at flexion angles above 22 degrees. These results may help the design of rational regimes of rehabilitation after ligament injury or repair.
To examine the hypotheses that anterior cruciate ligament (ACL) reconstruction improves the proprioception of the knee beyond the level of ACL-deficient knees, and that proprioception of the knee correlates well with knee function after ACL reconstruction.
Fifty-three patients with ACL-reconstructed knees (22 men and 31 women), 30 physically active healthy volunteers with normal knees (15 men and 15 women), and 30 patients with chronic ACL-deficient knees (15 men and 15 women).
A stabilometric assessment, which is considered to be a useful method for evaluating proprioception objectively, was used to compare the one-leg standing balance among three groups; and the relationship between subjective knee function, satisfaction, hop index, knee laxity, isokinetic thigh muscle strength, and one-leg standing balance in the ACL-reconstructed patients was also analyzed.
The one-leg standing balance of the patients with ACL-reconstructed knees was still impaired compared with that of healthy volunteers (men, p < 0.05; women, p < 0.01), but significantly better than that of the patients with ACL-deficient knees (men, p < 0.001; women, p < 0.001). The one-leg standing balance of the patients with ACL-reconstructed knees correlated well with their functional outcomes such as subjective knee function (men, p < 0.001; women, p < 0.01), satisfaction (men, p < 0.01; women, p < 0.001), and hop index (men, p < 0.001; women, p < 0.001), whereas poor correlation was seen between functional outcomes and mechanical stability.
The results suggest that knee function after ACL-reconstruction should be closely related with knee proprioception, and indicate that the usefulness of stabilometric assessment in the evaluation of the function of ACL-reconstructed knees.
Proprioception of the knee was measured in 19 healthy individuals to evaluate whether there were any differences between extension and flexion movements from two different starting positions. The threshold before detecting a passive movement, visual estimation on a protractor of a passive change in position (30 degrees angular change) and active reproduction of the same angular change were registered. The reference population was tested twice to study normal variation and reproducibility, followed by the evaluation of 20 patients with chronic, symptomatic and unilateral anterior cruciate ligament (ACL)-deficient knees. In the normal population no differences were found between the right and the left leg, men and women, or measurements made at the first and at the second test occasion. The thresholds from a starting position of 20 degrees were lower for extension than for flexion. When comparing the thresholds for extension between the 20 degrees and the 40 degrees starting position, lower values were found in the more extended position. The thresholds for flexion were lower from the 40 degrees starting position than from the 20 degrees starting position. The active reproduction of an angular change of 30 degrees was more accurate during flexion (30 degrees-60 degrees) than during extension (60 degrees-30 degrees). There were no differences in the reproduction tests or in thresholds from the 40 degrees starting position between the patients and the normal group, but the patients had higher thresholds from the 20 degrees starting position, in movements towards both extension 1.0 degree (range 0.5 degree-12.0 degrees) and flexion 1.5 degrees (range 0.5 degree-10.0 degrees) than the normal group 0.75 degree (range 0.5 degree-2.25 degrees) (P = 0.01) and 1.0 degree (range 0.5 degree-3.0 degrees) (P = 0.06), respectively. Thus, information of passive movements in the nearly extended knee position was more sensitive towards extension than towards flexion in threshold tests and the sensitivity improved closer to full extension, which implies a logical joint protective purpose. In this nearly extended knee position, which is the basis for most weight-bearing activities, patients with symptomatic ACL-deficient knees had an impaired awareness in detecting a passive movement. There were no differences in the more flexed position or in the reproduction tests between the patients and the normal group, and reproduction tests in the present form seem less appropriate to use in the evaluation of ACL injuries.