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The use of a valgus brace can effectively relieve the symptoms of unicompartmental osteoarthritis of the knee. This study provides an objective measurement of function by analysis of gait symmetry. This was measured in 30 patients on four separate occasions: immediately before and after initial fitting and then again at three months with the brace on and off. All patients reported immediate symptomatic improvement with less pain on walking. After fitting the brace, symmetry indices of stance and the swing phase of gait showed a consistent and immediate improvement at 0 and 3 months, respectively, of 3.92% (p = 0.030) and 3.40% (p = 0.025) in the stance phase and 11.78% (p = 0.020) and 9.58% (p = 0.005) in the swing phase. This was confirmed by a significant improvement at three months in the mean Hospital for Special Surgery (HSS) knee score from 69.9 to 82.0 (p < 0.001). Thus, wearing a valgus brace gives a significant and immediate improvement in the function of patients with unicompartmental osteoarthritis of the knee, as measured by analysis of gait symmetry.
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VOL. 82-B, N
. 7, SEPTEMBER 2000 1001
E. R. C. Draper, PhD, MIMechE, CEng, Principal Clinical Bioengineer
J. Sanchez-Ballester, FRCS Ed, Specialist Registrar
N. Hunt, FRCS, Specialist Registrar
J. R. Robinson, MRCS, Specialist Registrar
Department of Trauma and Orthopaedic Surgery, Imperial College School
of Medicine, 7th Floor East, Charing Cross Hospital, Fulham Palace Road,
London W6 8RF, UK.
R. K. Strachan, FRCS Ed, Consultant Orthopaedic Surgeon
J. M. Cable, RGN, P Tech Cert, Nurse Practitioner
Department of Orthopaedics, Ealing Hospital, Uxbridge Road, Southall,
Middlesex UB1 3HW, UK.
Correspondence should be sent to Dr E. R. C. Draper.
©2000 British Editorial Society of Bone and Joint Surgery
0301-620X/00/710638 $2.00
Improvement in function after valgus bracing
of the knee
E. R. C. Draper, J. M. Cable, J. Sanchez-Ballester, N. Hunt,
J. R. Robinson, R. K. Strachan
From Imperial College School of Medicine and Ealing Hospital, London, England
he use of a valgus brace can effectively relieve the
symptoms of unicompartmental osteoarthritis of
the knee. This study provides an objective
measurement of function by analysis of gait symmetry.
This was measured in 30 patients on four separate
occasions: immediately before and after initial fitting
and then again at three months with the brace on and
off. All patients reported immediate symptomatic
improvement with less pain on walking. After fitting
the brace, symmetry indices of stance and the swing
phase of gait showed a consistent and immediate
improvement at 0 and 3 months, respectively, of
3.92% (p = 0.030) and 3.40% (p = 0.025) in the stance
phase and 11.78% (p = 0.020) and 9.58% (p = 0.005) in
the swing phase. This was confirmed by a significant
improvement at three months in the mean Hospital
for Special Surgery (HSS) knee score from 69.9 to
82.0 (p < 0.001). Thus, wearing a valgus brace gives a
significant and immediate improvement in the function
of patients with unicompartmental osteoarthritis of
the knee, as measured by analysis of gait symmetry.
J Bone Joint Surg [Br] 2000;82-B:1001-5.
Received 7 October 1999; Accepted after revision 7 April 2000
Osteoarthritis of the knee occurs more often in the medial
presumably due to its increased loading
during gait. The load on the knee during the stance phase is
a combination of compression due to body mass and, with
the exception of a fleeting abduction at initial stance, an
adduction moment.
The consequence of this external
moment is that the centre of pressure within the knee
moves medially, increasing the load on the medial
Traditional conservative methods of treatment, such as
weight loss, walking aids, wearing a heel wedge
analgesia, may temporarily ameliorate symptoms improv-
ing function and walking distance, but they fail to address
the underlying pathology. Many of these patients will
ultimately require total knee arthroplasty. Although osteo-
arthritis can be treated surgically, there are many patients
for whom this is inappropriate, because of medical com-
orbidity, old age or other circumstances. In young patients
it is desirable to delay primary arthroplasty. The object of
other surgical treatments, such as high tibial osteotomy or
unicompartmental arthroplasty, is to transfer the load to the
less affected lateral compartment.
Such procedures carry
the usual surgical risks, increase the possibility of compli-
cations for the subsequent arthroplasty
and are not suitable
for patients of all ages.
The concept of a valgus brace is to apply, during stance,
an external abduction moment to the knee, which directly
opposes the usual adductor moment and should unload the
degenerative medial compartment. The term ‘valgus brace’
derives from this applied abduction, or valgus, moment.
Horlick and Loomer
and Pollo et al
have shown that
symptomatic relief can be provided by these braces and
Lindenfeld et al
found that valgus braces could reduce the
adductor moment around the knee. It is clear that wearing a
valgus brace may delay the requirement for surgery in
relatively young patients.
The study of Kirkley et al
compared the results of a prospective, randomised clinical
trial using three types of treatment: medical treatment only
or with a neoprene sleeve or a valgus brace. Their results
indicated that patients who have osteoarthritis of the medial
compartment may benefit significantly from the use of a
knee brace in addition to standard medical treatment. The
group with valgus braces had, on average, significantly
better outcome scores than that with neoprene sleeves.
In these studies no objective measurements of function
when using a valgus brace were made. This was the aim of
the present study. The relatively new technique of gait
symmetry analysis (GSA)
uses a treadmill with left and
right forceplates under a belt to record consecutive steps
(usually between 20 and 60). Several parameters can be
calculated from each step, including the duration of stance
and swing phases. The measured parameters are then used
to compare the braced with the contralateral limb. A direct
ratio, the symmetry index, has been found to be the most
useful and easily understood method of presenting the
results. It defines perfect symmetry and shifts either
towards or away from it. An important advantage over
functional scoring such as the Hospital for Special Surgery
(HSS) knee score, is that GSA can measure changes
Patients and Methods
The patients were measured and assessed immediately
before fitting the brace. All had received conservative
treatment only. These data were taken as the control for
each patient and consequently, paired comparisons between
visits were possible, allowing the use of more sensitive
statistics (paired Student t-test). This trial was therefore a
prospective controlled comparison of function before and
after use of the brace.
We excluded patients who were over 70 or under 35
years of age and those who had a varus deformity greater
than 12° or a fixed flexion deformity greater than 10°,
significant hip, back or contralateral leg symptoms, an
arthroscopy of the knee within the preceding six months
and physical or mental inability to comply with the require-
ments of wearing a brace.
There were 18 men and 12 women with a mean age of
56.2 years (35 to 70) who attended a specialist knee clinic
between October 1997 and May 1999. They had radio-
logically demonstrable osteoarthritis of the medial compart-
ment of the knee (Larsen grades II to IV) on anteroposterior
and Schusse radiographs with relative sparing of the lateral
compartment (Larsen grade 0 to I) which was consistent
with their symptoms.
Each patient was fitted with a custom-made valgus brace,
the GII ADJ Unloader (GII Orthotics Europe, Belgium).
This comprises two semirigid plastic shells, for the thigh
and calf, linked by a polyaxial medial hinge set at 4° of
valgus. An adjustable tension strap crosses the lateral
aspect of the knee from below, posterolaterally to above,
anteromedially, from the calf to the thigh shells (Fig. 1).
The same technician obtained the negative casts, fitted
the braces and instructed the patients in the proper use and
care of the brace. The patients were measured and assessed
before and immediately after fitting the brace and again
after continuous wear of the brace for three months.
Instrumented treadmill. A standard running machine
(PowerJog 200; Sport Engineering, Birmingham, UK) was
modified to house two independent forceplates, one placed
on the left and the other on the right of the bed. Each plate
was supported at each corner by an electrical resistance
strain-gauge transducer designed to be sensitive only to the
vertical component of force. The signals from each trans-
ducer were amplified and digitised by a standard laboratory
system (National Instruments Corp, Austin, Texas). A pro-
gram written within LabView (National Instruments Corp)
on a personal computer recorded the signals for later
Walking tests were performed only if the subject felt
confident enough to start and complete the exercise. Sub-
jects were asked to walk on the instrumented treadmill,
wearing their normal shoes (Fig. 2). Both the subject and
the operator were in a position to operate the controls at all
times. During the first test, patients selected their own
preferred walking speed; this was recorded and used for all
subsequent testing of that patient. Four tests were per-
formed, one immediately before and one immediately after
the initial fitting of the brace; the other two were performed
consecutively, and within minutes of each other, with and
Fig. 1a Fig. 1b
Photograph (a) and diagram (b) showing the valgus
without the brace, after three months. Each test lasted for
one minute, during which time between 20 and 60 steps
were recorded.
Analysis began with a visual inspection of the data to
remove any invalid steps if the patient had faltered. A
macro was incorporated into the system which marked for
scrutiny, and possible exclusion, any step that exceeded two
s of the mean for any measured parameter.
A series of Visual Basic macros in Microsoft Excel was
used in the analysis. They automatically detected the heel
strike and toe-off, thereby isolating each step. After this the
stance phase and swing times, among other parameters,
were calculated for each step, both left and right. Symmetry
indices (SI) were then calculated for the stance and swing
phases. An SI is defined as the ratio of the means of the
parameter measured from the affected limb divided by that
of the unaffected limb. These can be calculated for any
measurement; those for stance and swing phase alone were
used in this study.
Any change in an SI can easily be seen and understood.
An SI of 1 indicates a perfectly symmetrical gait. A shift
towards 1 with time indicates an improvement, whereas a
shift away indicates deterioration.
Clinical assessment. Patients were assessed clinically
using visual analogue pain scores for resting, standing,
walking and climbing stairs. A modified HSS knee score,
activity questionnaires and requirement for analgesia were
also recorded. The radiological grade of osteoarthritis in
each of the three compartments was noted and the mechan-
ical femorotibial axis was determined from full-length
weight-bearing radiographs.
GSA compared with HSS score. In order to validate the
use of GSA, HSS scores were calculated initially and after
three months. The initial score before bracing was com-
pared with the SI taken at the same time. The scores at the
second visit were assessed from activity during the pre-
vious three months in which the brace was worn. Conse-
quently, comparison at this point was with the SI while
wearing the brace and with that at the first visit. It can be
seen in Figure 3 that the three outcome measurements show
an improvement; in all cases this is significant (p < 0.05).
Although the greatest change in the mean improvement
VOL. 82-B, N
. 7, SEPTEMBER 2000
Fig. 2
GSA walking test (using a modified, standard running
Fig. 3
Validation of symmetry indices by comparison with HSS score (mean ±
appears in the HSS score, the differences at three months
between the measurements are not significant (p > 0.05). It
was felt therefore that the SI had a similar capacity to
detect any underlying change in function as the HSS score.
The advantage of GSA was that it could be performed
immediately before and after fitting the brace, whereas the
modified HSS scoring system requires the passage of time
between tests.
At the initial examination the mean modified HSS score
was 69.93 (47 to 87). All patients reported moderate to
severe pain on walking, with a mean of 7.57 on the ten-
point visual analogue score for this activity. The mean
score for resting and standing was less at 2.30 (0 to 7) and
4.00 (0 to 7), respectively. All patients had Larsen grade II
or III (24 and 6, respectively) in the medial compartment
and grade 0 or I (16 and 14, respectively) in the lateral
compartment. All patients except one had an abnormal
varus mechanical axis at the knee (one patient had a valgus
mechanical axis of 2°) with a mean of 4.82° of varus
ranging from -2° (valgus axis) to +12°. All patients report-
ed subjective improvements in their symptoms, with less
pain on walking on the treadmill with the brace fitted.
With an antalgic gait, it can be expected that the subject
will tend to spend less time on the affected limb. This will
lead to a stance-phase SI of below 1 and a swing-phase SI
above 1, both of which have been observed in this study. A
more symmetrical gait, which is assumed to be an improve-
ment, will result in each SI shifting towards 1. This is
summarised in Table I and clearly demonstrated in Figure
4; the change in both indices is significant (p < 0.05). The
mean HSS score also improved significantly from 69.93
) at the initial visit, to 82.04 (±10.65
) at the
three-month visit.
Patients with unicompartmental osteoarthritis of the knee
can be helped by the use of a valgus brace. Clinical studies
of this
have relied on subjective scoring systems. The
objective outcome measurements made in our study sup-
port these previous findings and show that the improvement
in function begins as soon as the brace is worn. Figure 4
clearly shows this improvement, with a significant shift
towards a value of 1 (perfect symmetry) for both the stance
and swing phases of gait. This effect is detectable at the
first fitting and is maintained three months later.
Although this shows that this design of brace is clinically
effective, it sheds little light on the mechanism. It is clear
that without the brace our patients tend to bear weight for
longer on the unaffected limb, while sparing the affected
limb for longer. This is typical of an antalgic gait. The
return to a more symmetrical pattern indicates less
There are, however, many parameters other than pain
which may also disturb the pattern of gait. These include
changes in proprioception and a lack of confidence in the
affected limb. Despite the fact that our study does not
Table I. Mean (±
) stance- and swing-phase symmetry indices
Initial visit Three-month visit
No brace Braced No brace Braced
Stance phase 0.97 ± 0.11 1.02 ± 0.10 0.97 ± 0.11 1.01 ± 0.12
p=0.030 p = 0.025
Swing phase 1.13 ± 0.32 1.01 ± 0.17 1.12 ± 0.29 1.02 ± 0.18
p=0.020 p = 0.005
Fig. 4
Symmetry indices with and without
valgus brace (mean ±
explain the mechanisms which are responsible for improv-
ing symptoms, it does add objective evidence that valgus
bracing for unicompartmental osteoarthritis of the knee is
clinically effective.
Further work is required to determine if the effectiveness
of this type of brace is reduced with time, to investigate the
alteration in internal load of the knee when the brace is worn
and to determine whether there are biological consequences
of unloading a degenerative area of articular cartilage.
We thank Mr Shalaby and Mr Thomas for their support in this trial,
Professor Hughes for his tireless enthusiasm and Action Research for
providing the funding for the treadmill modifications (Project Number A/
One of more of the authors have received or will receive benefits for
personal or professional use from a commercial party related directly or
indirectly to the subject of this article.
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5. Insall JN, Joseph DM, Msika C. High tibial osteotomy for varus
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... Many studies have found significant asymmetry between hemiplegic limbs and nonhemiplegic limbs in stroke patients. The hemiplegic limbs have a slow gait rate, and their dysfunction leads to short standing durations, prolonged swinging durations, and reduced ground responses [36][37][38] , leading to insufficient power and poor progress. To adapt to this compensatory dysfunction, patients need to rely on the nonhemiplegic limb to maintain balance and push forwards, resulting in biomechanical changes of the nonhemiplegic limb, presenting with an erratic gait 39 . ...
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Genu recurvatum in stroke patients with hemiplegia causes readily cumulative damage and degenerative changes in the knee cartilage. It is important to detect early cartilage lesions for appropriate treatment and rehabilitation. The purpose of this cross-sectional study was to provide a theoretical basis for the early rehabilitation of hemiplegia patients. We used a zero TE double-echo imaging sequence to analyse the water content in knee joint cartilage at 12 different sites of 39 stroke patients with genu recurvatum and 9 healthy volunteers using a metric similar to the porosity index. When comparing the hemiplegic limb vs. the nonhemiplegic limb in patients, the ratios of the deep/shallow free water content of the femur cartilages at the anterior horn (1.16 vs. 1.06) and posterior horn (1.13 vs. 1.25) of the lateral meniscus were significantly different. Genu recurvatum in stroke patients with hemiplegia can cause changes in the moisture content of knee cartilage, and the changes in knee cartilage are more obvious as the genu recurvatum increases. The "healthy limb" can no longer be considered truly healthy and should be considered simultaneously with the affected limb in the development of a rehabilitation treatment plan.
... Many studies have found significant asymmetry between hemiplegic limbs and nonhemiplegic limbs in stroke patients. The hemiplegic limbs have slow gait rate, and their dysfunction leads to short standing time, prolonged swinging time, and reduced ground response [36][37][38], leading to insufficient power and poor progress. In order to adapt to this compensatory dysfunction, patients need to rely on the non-hemiplegic limb to maintain balance and push forward, resulting in biomechanical changes of the non-hemiplegic limb, presenting spastic gait [39]. ...
Full-text available
-BACKGROUND: Genu recurvatum in stroke patient hemiplegia causes readily cumulative damage and degenerative changes of knee cartilage. It is important to detect early lesions of cartilage for appropriate treatment and rehabilitation. -PURPOSE: The purpose is to provide theoretical basis for early rehabilitation of hemiplegia patients. -STUDY TYPE: Cross-sectional study. -POPULATION: 39 Stroke patients with genu recurvatum and 9 healthy volunteers. -SEQUENCE: We used zero TE double echo imaging sequence. -ASSESSMENT: Analyze the water content in knee joint cartilage at 12 different sites of stroke patients with genu recurvatum using a method similar to porosity index. -STATISTICAL TESTS: Statistical analysis was performed using SPSS 17.0 statistical software. The mean ± standard deviation was used to represent the mean. The independent sample t test was used for all mean comparisons. When the data did not conform to the normal distribution or variance heterogeneity, the non-parametric test was used. P< 0.05 was considered statistically significant. -RESULTS: When compared hemiplegia limb vs. non-hemiplegia limb in patients, the ratio of deep/shallow free water content of the cartilages at the junction of the femur and anterior horn (1.16 vs. 1.06) and posterior horn (1.13 vs. 1.25) of lateral meniscus were significant differences (P<0.05). -DATA CONCLUSION: Conclusion is that Genu recurvatum in stroke patients with hemiplegia can cause changes in moisture content of knee cartilage, and the changes of knee cartilage are more obvious with the increase of genu recurvatum. The so-called "healthy limb" is no longer the real meaning of healthy limb, and should be considered simultaneously with the affected limb in the development of rehabilitation treatment plan.
... In this research, though the HSS knee score improved in both groups after treatment, the amelioration of the HSS knee score in the fibulectomy group was better than that in the drug group at last follow-up with statistical differences. In our study, the HSS knee score in the partial fibulectomy group increased by 40.9% compared with increases of 30.7% [5], 29.4% [5], 17.3% [16], 28.5% [6], and 49.2% [17] reported for treatment with lateral wedge insoles, acupuncture, knee braces, toe-out gait modification, and opening wedge HTO, respectively. ...
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Background: Upper partial fibulectomy has been preliminarily proved to have the efficacy for pain alleviation and improvement of function in patients with mild to moderate medial compartment knee osteoarthritis (KOA). However, the previous studies lack the control group with other treatments. The aim of this prospective, randomized controlled study is to compare the clinical and biomechanical effects between upper partial fibulectomy and drug conservative treatment on improvement of clinical pain, function, and gait for patients with mild to moderate medial knee osteoarthritis (KOA) and further discuss its biomechanical mechanism. Methods: From August 2016 to February 2017, 49 and 48 patients with mild to moderate medial KOA were allocated to fibulectomy and drug groups. We assessed the patients' visual analog scale (VAS) pain score, Hospital for Special Surgery (HSS) knee score, limb alignment, passive flexion/extension range of motion (ROM) of the knee, and 3D gait kinematics and kinetics parameters before and after intervention. Repeated-measures ANOVA with Dunnett's post hoc assessment and multivariate analysis of variance were applied for intragroup and intergroup comparisons, respectively. Results: The improvement in the fibulectomy group on the VAS pain score, HSS knee score, walking speed, and walking knee range of motion (ROM) was statistically better than that in the drug group. The decreased overall peak knee adduction moment (KAM) (decreased by 16.1%) and hip-knee-ankle (HKA) angle (decreased by 0.99° from a more varus alignment to a more neutral alignment) of the affected and operated side 1 year after surgery were observed in the fibulectomy group. Conclusion: This research demonstrated that as a biomechanical intervention, upper partial fibulectomy can be a better choice in pain relief and function and gait improvement than drug conservative treatment for patients with early-stage knee OA. The long-term clinical outcomes, indication, and rationale for the improvement in clinical symptoms should be investigated further.
... 55 Nonetheless, there is evidence that the global reduction in pain associated with consistent use of knee braces may facilitate correction of gait asymmetry and improvement in function. 56 Although promising data exist, the variability across these different trials suggests that more robust clinical trials are needed before an unequivocal recommendation can be made on behalf of knee braces for the treatment of OA. ...
The goal of the practitioner managing a patient with knee osteoarthritis (OA) is to minimize pain and optimize their function. Several noninterventional (noninjectable) therapies are available for these individuals, each having varying levels of efficacy. An individualized approach to the patient is most beneficial in individuals with knee OA and the treatment plan the practitioner chooses should be based on this principle. The focus of this article is to provide an up-to-date overview of the treatment strategies available, evidence to support them, and in whom these treatments would be most appropriate. These include exercise (aerobic and resistance), weight loss, bracing and orthotics, topical and oral analgesic medications, therapeutic modalities, and oral supplements.
... The majority of included studies were of level 2 evidence (n = 14) (Table 1). 2,7,11,13,16,18,19,21,22,25,33,44,49,51 There were 3 studies of level 1 evidence, 27,39,45 7 studies of level 3 evidence, 12,14,17,26,47,48,52 and 5 studies of level 4 evidence. 20,23,29,30,32 The mean MINORS score was 12.3 ± 1.9, which indicates fair quality of evidence for nonrandomized studies. ...
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Context: Knee osteoarthritis affects 9.3 million adults over age 45 years in the United States. There is significant disability associated with this condition. Given the potential complications and the significant cost to the health care system with the dramatic increase in total knee arthroplasties performed for this condition, assessment of the efficacy of nonoperative modalities, such as offloading knee braces, is essential as part of optimizing nonoperative treatment for this condition. Objective: To determine the effectiveness of valgus offloader braces in improving clinical outcomes for patients with medial compartment knee osteoarthritis. Data Sources: Three databases (PubMed, MEDLINE, and EMBASE) were searched from data base inception through July 28, 2017. Study Selection: Studies reporting outcomes of valgus offloader knee braces in the treatment of medial compartment knee osteoarthritis were included. Study Design: Systematic review. Level of Evidence: Level 4. Data Extraction: Data pertaining to demographics, descriptive statistics, and clinical outcomes were extracted from the included studies. The methodological quality of included studies was evaluated. Results: A total of 31 studies were included, with a total of 619 patients. The majority of studies reported improved pain outcomes using valgus offloader braces. However, variable results were reported as to whether valgus offloader braces significantly improved functional outcomes and stiffness. Offloader bracing was more effective at reducing pain when compared with neutral braces or neoprene sleeves. Conclusion: Valgus offloader bracing is an effective treatment for improving pain secondary to medial compartment knee osteoarthritis. The literature remains unclear on the effectiveness of valgus offloader braces with regard to functional outcomes and stiffness. Larger prospective randomized trials with consistent outcome assessment tools and consideration of patient compliance would be beneficial to more accurately determine treatment effects of valgus offloader bracing.
... 1-All Correspondences to: Fatemeh Zare Zadeh; Email:<> 2-PhD Student One cross-sectional study suggested that valgus braces immediately improved the function of the patient with unicompartmental osteoarthritis of the knee (13). A randomized clinical trial by Kirkley et al also showed that unloader knee orthoses were effective in improving quality of life and function in knee OA patients (7). ...
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Objectives: Patients suffering from mild to moderate knee osteoarthritis may be treated with unloader knee orthoses or laterally wedged insoles. The aim of this study was to identify and compare the effects of two orthoses in these patients. Methods: 56 patients with medial compartment knee OA were evaluated when wearing an unloader knee orthosis and insoles with a 6° lateral wedge which were randomly assigned. Testing was performed at baseline and after 6 months of use with the two types of orthoses. The KOOS score was used to assess outcomes in this study. A paired T test was used for comparing base line and the 6th month post interventions KOOS sub scale score. An independent T test was used for analyzing the efficacy between the two orthoses. Results: Each of the interventions improved all parameters compared to the baseline condition (P=0.000). However, in comparing the effect between these orthoses, we did not find significant differences in activities of daily living (P=0.871), or sports and recreational activities (P=0.351). The pain and symptoms (P=0.000) were, however, significantly different between the two interventions. Discussion: The unloader knee orthoses were more effective than lateral wedge insoles in reducing pain and symptoms.
... The primary aim of this thesis was to explore the use of an instrumented treadmill as a tool to assess higher gait performance. Specifically our goal was to test patients with different types of joint replacement and knee osteoarthritis at higher speeds than that which has been previously reported in case differences existed which may have been undetectable at slower Analysis of gait asymmetry has already been described in clinical practice especially with regards to performance(55), injury (36) and medical technology (111). However, most studies have assessed knee osteoarthritis patients at slower speeds (40) and with conventional methods (112). ...
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.
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Objective To investigate the effect of residual varus and valgus deformity on the stress distribution of the knee joint after tibial fracture malunion. Methods Fourteen adult cadaver specimens were selected to establish the models of tibial fractures, which were fixed subsequently at neutral position (anatomical reduction) and malunion positions (at 5°, 10°, and 15° valgus positions, and 5°, 10°, and 15° varus positions). The stress distribution on the medial and lateral plateau of the tibia was quantitatively measured using ultra‐low‐pressure sensitive film technology. The changes in the stress distribution of the knee joint after tibial fracture malunion and the relationship between the stress values and the residual varus or valgus deformity were analyzed. Results Under 400 N vertical load, the stress values on the medial and lateral plateau of the tibia at the neutral position were 1.137 ± 0.139 MPa and 1.041 ± 0.117 MPa, respectively. When compared with the stress values measured at the neutral position, the stress on the medial plateau of the tibia was significantly higher at varus deformities and lower at valgus deformities, and the stress on the lateral plateau was significantly higher at valgus deformities and lower at varus deformities (all P < 0.05). The stress values on the medial plateau of the tibia were significantly higher than the corresponding data on the lateral plateau at neutral and 5°, 10°, and 15° varus deformities, respectively (all P < 0.05), and significantly lower than the corresponding data on the lateral plateau at 5°, 10°, and 15° valgus deformities, respectively (all P < 0.05). Conclusion Residual varus and valgus deformity after tibial fracture malunion can lead to obvious changes of the stress distribution of the knee joint. Therefore, tibial fractures should be reduced anatomically and fixed rigidly to avoid residual varus–valgus deformity and malalignment of lower limbs.
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We assessed short-term treatment results of younger patients with varus malalignment and chronic anterior cruciate ligament deficiency. Forty-one patients (mean, 32 years; range, 16 to 47) underwent a high tibial osteotomy. Because of giving way symptoms, 14 also had a lateral iliotibial band extraarticular procedure at the time of the osteotomy and 16 had an intraarticular anterior cruciate ligament allograft reconstruction after the osteotomy. All returned for followup (mean, 58 months; range, 23 to 86), which included KT-1000 arthrometer testing and evaluation by our knee rating system. Statistically significant ( P < 0.05) improvements were found in the mean overall rating scores for pain, swell ing, and giving way. Preoperatively, 30 (73%) had pain with activities of daily living or with any sports activity; 11 (27%) could perform only light sports activities with out pain. At followup, 32 patients (78%) had no pain with activities of daily living or light sports. Ten of 15 patients with advanced medial tibiofemoral arthrosis (subchondral bone exposure) had significant improvements in symptoms. Patient satisfaction was high: 88% stated they would undergo the procedure again and 78% felt their knee condition was improved. Patients who had the allograft reconstruction had significantly lower ( P < 0.05) anterior-posterior dis placements at followup than those who had the extraar ticular procedure. We concluded that osteotomy should be performed early in the disease process for younger athletes who experience symptoms with activity. It may be unrealis tic, however, to expect continuation of sports beyond light recreational, given the joint arthrosis that is usually present and the high in vivo joint loadings with athletes. Anterior cruciate ligament reconstruction should be considered when giving way previously occurred and the patient plans to resume athletics. However, patients with advanced arthrosis can avoid anterior cruciate ligament surgery by reducing athletic activities.
A double crossover study was designed and carried out on 39 patients to test the efficacy of valgus bracing using a GII brace in patients with medial gonarthrosis. Two brace designs were studied-one with a medial and one with a lateral hinge. The double crossover technique involved evaluating each patient under conditions of no brace, brace in neutral, and brace in valgus, each for a period of 6 weeks. Pain and function were recorded by subjects on diary forms daily and at the end of each week. Standing posterior-anterior radiographs were done on all patients under conditions of weight bearing, nonweight bearing, without brace, and with brace in valgus. Statistical analysis using repeated measures analysis of variance showed statistically significant pain relief compared to baseline with both a lateral hinge in valgus (p = 0.02) and a medial hinge in valgus (p < 0.0001). No significant change in function was found and no significant radiographic evidence of change in femoral-tibial angle or joint space alteration was demonstrated. Seventy-four percent of patients purchased their brace at the end of the study. Follow-up at an average 20 months after the study showed 58% of the patients with a lateral hinge and 93% of the patients with a medial hinge were still using their braces as the principal form of therapy. Valgus bracing using a GII brace, especially with a medial hinge, can be a useful treatment modality for reducing pain in the patient with medial gonarthrosis to replace or delay surgery. (C) Lippincott-Raven Publishers.
From this study of 213 knees it appears that 61.8% of the patients rated themselves as having less pain than before osteotomy even after 10 years from the time of surgery. Functionally, 64.7% were better. Rarely did a patient believe that his pain was worse than it was preoperatively, even up to 10 years after the surgery; nor did any patient believe that his functional status was compromised further by the operation. The conclusions drawn from the most recent study are the following. Upper tibial osteotomy for gonarthrosis and varus deformity relieves pain and restores function in more than 60% of the patients, even 10 years after the operation. The major complication is recurrence of deformity, in part, at least, the cause of recurring pain. It can be minimized by achieving at least 7 degrees of valgus axial alignment (up to 10 degrees is allowable), and by excluding from operation knees with bicompartmental involvement.
We evaluated the results in eighty-three patients (ninety-five knees) who had had a high tibial osteotomy for either unicompartmental osteoarthritis or osteonecrosis. The operations were performed between 1965 and 1976. The mean length of follow-up was 8.9 years (range, five to fifteen years). The early results were promising: at two years 97 per cent and at five years 85 per cent of the knees had either an excellent or a good result. At subsequent follow-up, however, only sixty knees (63 per cent) had an excellent or good result, and in the remainder recurrent pain had developed. Twenty-two knees (23 per cent) had been revised to a total knee arthroplasty because of pain. The alignment obtained by the osteotomy was not as important in determining the long-term result as we had previously believed. Although recurrent varus deformity was observed in more than one-quarter of the knees, it was not necessarily associated with an unsatisfactory result. The passage of time was the most important factor in determining the result, as only fifteen (37 per cent) of the knees that had been followed for more than nine years were pain-free. We now believe that total knee arthroplasty is a more suitable operation for patients who are more than sixty years old and that high tibial osteotomy should be reserved for patients who have a strenuous occupation or who wish to continue to participate in sports activities.
A stylized wedge-shaped defect was created in the medial plateau of autopsy specimens of the tibia to evaluate methods for fixation in total knee arthroplasty. A series of tibial components was inserted by five different methods. With each method loading of up to 1780 N axially and a varus load of 1340 N at 28 Newton-meters were assessed. The vertical deflections of the medial and lateral sides of the tray relative to the bone were measured while bending of the stem was recorded with strain gauges. The greatest deflections occurred when cement alone filled the defect; only slight improvement resulted from the addition of two cancellous screws to buttress the metal tray. Further improvement occurred when solid spacers of Plexiglas or metal were used. Finally, the most secure support was obtained with an integral custom-made tibial component. A central stem 70 mm long carried 23%-38% of the axial load, considered useful in the situation of deficient proximal bone. A metal wedge was considered an acceptable alternative to a custom-made component and may prove useful in the reconstruction of tibial bone stock defects.
The purpose of this study was to determine whether a brace designed to unload varus degenerative knees actually alters medial compartment loads by decreasing the adduction moment. Eleven patients who had arthrosis confined to the medial compartment were fitted with a valgus brace and tested before and after brace wear with pain and function scoring instruments and by automated gait analysis. The biomechanical data from these patients were compared with those from 11 healthy control subjects. Scores from an analog pain scale decreased 48% with brace wear, and function with activities of daily living increased 79%. Mean adduction moment without the brace measured 4.0 +/- 0.8% body weight times height versus 3.6 +/- 0.8% body weight times height when wearing the brace (10% decrease). The mean adduction moment for control subjects was 3.5 +/- 0.6% body weight times height. Thus, the mean adduction moment decreased from approximately one standard deviation from the normal mean to a value that is similar to the control value. Nine of 11 patients had a decrease in the adduction moment with the brace, five of 11 patients had a reduction higher than 10%, and decreases in this moment were as high as 32%. This study shows that pain, function, and biomechanical knee loading can be altered by a brace designed to unload the medial compartment of the knee.
The purpose of this study was to compare a custom-made valgus-producing functional knee (unloader) brace, a neoprene sleeve, and medical treatment only (control group) with regard to their ability to improve the disease-specific quality of life and the functional status of patients who had osteoarthritis in association with a varus deformity of the knee (varus gonarthrosis). The study design was a prospective, parallel-group, randomized clinical trial. Patients who had varus gonarthrosis were screened for eligibility. The criteria for exclusion included arthritides other than osteoarthritis; an operation on the knee within the previous six months; symptomatic disease of the hip, ankle, or foot; a previous fracture of the tibia or femur; morbid obesity (a body-mass index of more than thirty-five kilograms per square meter); skin disease; peripheral vascular disease or varicose veins that would preclude use of a brace; a severe cardiovascular deficit; blindness; poor English-language skills; and an inability to apply a brace because of physical limitations such as arthritis in the hand or an inability to bend over. Treatment was assigned on the basis of a computer-generated block method of randomization with use of sealed envelopes. The patients were stratified according to age (less than fifty years or at least fifty years), deformity (the mechanical axis in less than 5 degrees of varus or in at least 5 degrees of varus), and the status of the anterior cruciate ligament (torn or intact). The patients were randomly assigned to one of three treatment groups: medical treatment only (control group), medical treatment and use of a neoprene sleeve, or medical treatment and use of an unloader brace. The disease-specific quality of life was measured with use of the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and the McMaster-Toronto Arthritis Patient Preference Disability Questionnaire (MACTAR), and function was assessed with use of the six-minute walking and thirty-second stair-climbing tests. The primary outcome measure consisted of an analysis of covariance of the change in scores between the baseline and six-month evaluations. One hundred and nineteen patients were randomized. The control group consisted of forty patients (thirty-one men and nine women; mean age, 60.9 years); the neoprene-sleeve group, of thirty-eight patients (twenty-seven men and eleven women; mean age, 58.2 years); and the unloader-brace group, of forty-one patients (twenty-eight men and thirteen women; mean age, 59.5 years). Nine patients withdrew from the study. At the six-month follow-up evaluation, there was a significant improvement in the disease-specific quality of life (p = 0.001) and in function (p< or =0.001) in both the neoprene-sleeve group and the unloader-brace group compared with the control group. There was a significant difference between the unloader-brace group and the neoprene-sleeve group with regard to pain after both the six-minute walking test (p = 0.021) and the thirty-second stair-climbing test (p = 0.016). There was a strong trend toward a significant difference between the unloader-brace group and the neoprene-sleeve group with regard to the change in the WOMAC aggregate (p = 0.062) and WOMAC physical function scores (p = 0.081). The results indicate that patients who have varus gonarthrosis may benefit significantly from use of a knee brace in addition to standard medical treatment. The unloader brace was, on the average, more effective than the neoprene sleeve. The ideal candidates for each of these bracing options remain to be identified.
It has been recognised for centuries that various conditions will lead to asymmetries in gait and several researchers have analysed symmetry of gait. However, in general such analyses are based on five steps or fewer. A new system has been designed and manufactured that is based on a motorised treadmill with forceplates (errors +3. 2% and -4.3%) that quickly gathers information on larger numbers of steps. It automatically records the data and then performs a semi automatic analysis to calculate various parameters from each of the measured steps, including: heel strike, toe off, stance phase, swing phase, peak forces and loading and unloading rates. Other parameters can also be easily incorporated into the analysis such as double support time. Student's t tests are performed comparing the means of these parameters. The ratios of the parameters, left to right (or uninvolved to involved limbs), are then quoted as Symmetry Indices. It has been found to be quick and easy to use and produces results that are both readily understood and clinically relevant.