No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Stress on the femoropatellar joint in downhill walking—a biomechanical study
Abstract
Kinematic and kinetic data were collected of 6 male and 6 female healthy subjects. For downhill walking a dismountable slope of 6 m length and a grade of 19.3% was built. Planar net joint moments and mechanical power at the knee joint were calculated for the sagittal view using force platform records based on standard inverse dynamics procedures. On the basis of a two dimensional knee model the patello femoral joint compressive forces were calculated. While the maximal extension moment for level walking was only 1.2 +/- 0.5 Nm/kg bw at a knee flexion angle of 20 degrees it was 2.6 +/- 0.6 Nm/kg bw at an angle of 40 degrees for downhill walking. This increased moment and knee flexion angle yields a 3 to 4 times bigger femoropatellar joint compressive force for downhill walking compared to level walking. Due to a smaller moment arm of female subjects the patello femoral joint compressive forces were bigger for females compared to males (14 N/kg bw for male subjects, 18 N/kg for female subjects during level walking and 50 N/kg bw for male subjects, 70 N/kg for female subjects during downhill walking). The femoropatellar joint compressive force for downhill walking is comparable to running, squatting or downstairs walking. Based on this investigation downhill walking must be considered a strenuous task for the femoro patellar joint and explains well why patients with anterior knee pain or osteoarthritis have problems during downhill walking.
... Follow-up examinations were scheduled at 1, 3, and 6 months after the operations. The evaluations of knee scores and functional scores were based on The Knee Society Clinical Rating System, (16) and The Knee Society Total Knee Arthroplasty Roentgenograhic Evaluation and Scoring System was adapted for radiographic examinations. ...
... Various studies have confirmed the abnormal loading of knee joint during heavy physical activity, particularly kneeling, squatting and crosslegged sitting. [10][11][12][13][14][15][16][17] It has been theorized that the PCL plays an important role in the femoral roll back mechanism, which is responsible for deep knee flexion. Furthermore, preserving the PCL may improve joint proprioception and thus the clinical outcome 18 . ...
Background: This prospective clinical study was performed to compare the clinical outcomes between patients with cruciate-retaining (CR) and cruciate-substituting (CS) total knee arthroplasty (TKA). Methods: from July 2018 to June 2019, 52 patients (32 females and 20 males) with a total of 70 knees with a mean age of 61.11 years (range, 46 to 78 years) were enrolled in this study. Patients were randomly divided into two groups including group A (Cruciate-Retaining Total Knee Arthroplasty (CR-TKA) underwent 35 CR TKA, and group B (Cruciate-Substituting Total Knee Arthroplasty (CS-TKA) underwent 35 CS total knee Arthroplasty. The evaluation parameters included knee scores, pain score, functional scores, radiographs of the knees and ROM (Range of motion). Regular follow up done at 4 weeks, 12weeks and then every 6 months. All data were collected and analyzed with the help of suitable statistical parameters. Results: Both designs give equal and good results. We preferred CR Knees in relatively young patients and patients with smaller knees as its bone conserving implant and CS knees in patients with Inflammatory arthritis, patient with severe Varus or flexion deformity, when tibia cut is more than 10 mm and when intra-operatively findings suggestive of non-functional posterior Cruciate ligament. However, in our short term randomized interventional study Posterior Cruciate substitution Total Knee Arthroplasty had a marginally better outcome than the posterior Cruciate retaining in terms of range of motion but it needs a long-term analysis. Key words: Cruciate substitution Total Knee Arthroplasty, Cruciate-Retaining Total Knee Arthroplasty, Knee scores, Pain score
... This means factors other than the exposure and extensor mechanism violation are involved in the reduced functionality after total knee arthroplasty. Various factors are associated with the onset and progression of osteoarthritis [1][2][3][4][5][6] . These include genetic factors, age, sex, obesity, occupation, abnormal loading of the joint in kneeling, squatting and cross-legged sitting. ...
... He concluded that the tibiofemoral loads range from 3.9 to 6.0 times BW. Jefferson et al 10 25 For some sports activities such as jumping 26 or weightlifting 27 the loads imposed on the patellofemoral joint are close to 20 times BW. A review of the available literature indicates that the majority of authors use the lowest tibiofemoral and patellofemoral joint loads reported for the evaluation of contact stresses in total joint replacement. ...
Estimates of knee joint loadings were calculated for 12 normal subjects from kinematic and kinetic measures obtained during both level and downhill walking. The maximum tibiofemoral compressive force reached an average load of 3.9 times body-weight (BW) for level walking and 8 times BW for downhill walking, in each instance during the early stance phase. Muscle forces contributed 80% of the maximum bone-on-bone force during downhill walking and 70% during level walking whereas the ground reaction forces contributed only 20% and 30% respectively.
Most total knee designs provide a tibiofemoral contact area of 100 to 300 mm ² . The yield point of these polyethylene inlays will therefore be exceeded with each step during downhill walking. Future evaluation of total knee designs should be based on a tibiofemoral joint load of 3.5 times BW at 20° knee flexion, 8 times BW at 40° and 6 times BW at 60°.
... In other words, the knee effectively acts as a torque dampening mechanism during downhill walking. These large extensor forces can lead to muscle fatigue and high stresses on the knee joint in the short term and increased risk of degenerative joint diseases in the long term [2]. Quasipassive exoskeletons have previously been evaluated for assisting the knee during level walking [3], load-carrying [4] and running [5]. ...
A pneumatic exoskeleton intended to decrease the muscle activity of the knee extensors during walking on a negative slope is presented. The device consists of an air spring that can be engaged and disengaged via a solenoid valve. When engaged, the air spring resists knee flexion. A preliminary evaluation of the device was conducted with a single healthy subject. During testing, the EMG activity of the rectus femoris decreased by 15 %, while the EMG activity of the vastus medialis increased by 8 %.
Background: Total knee arthroplasty has evolved over the past decades into a very much reliable surgical treatment for advanced arthritis of knee. Total knee replacement has been shown to restore patient function and relieve pain and deformity that results from knee arthritis. The success of a total knee replacement is determined by many factors like degree of pain relief and functional outcome. The role of Posterior cruciate ligament in total knee replacement is controversial. The first is to retain the ligament and to preserve as much as possible of the normal anatomy and function of the knee. Preservation of the ligament is thought to enhance stability, femoral rollback, mechanical advantage of the quadriceps muscle and proprioceptive properties. Theoretically it has been suggested that PCL retaining can increases the range of flexion and prevents posterior translation which reduces loosening and excessive polyethylene wear by decreasing the shear stresses at the fixation surfaces. We conducted a prospective study to compare resection with retention of PCL using a standard PCL–retaining cemented total knee replacement and assessed the functional outcome using functional knee scores and WOMAC score. Aims and Objectives: The aim of the study is to “prospectively compare the functional outcome between posterior cruciate ligament retaining and posterior cruciate ligament sacrificing total knee arthroplasty. Materials and Methods: The study was done on 20 patients admitted to Hi-Tech Medical College & Hospital, Bhubaneswar. Scoring system formulated by the WOMAC Score, Knee Society Knee Score and Functional Knee Score were used to evaluate the patients before and after surgery. Both knee scores and functional scores are calculated with each amounting to a total of 100 points and WOMAC Score with max of 96 points. All patients were evaluated postoperatively and followed up. Results: Analyzing the functional outcome it was found that all the patients in both the groups had significant improvement in their knee score and the functional knee score. Analyzing the total Knee Scores, the average Knee Society Score for the PS group was 85.80 and that of CR group was 75.60 and statistical analysis revealed a significant difference in the the p-value in favour of Cruciate Sacrificing Prosthesis signifying that Cruciate Sacrificing Prosthesis has better functional outcome. The functional knee society also showed a marked improvement in all patients, for CS group FKS was 99.6 and for CR group it was 91.6.The WOMAC Score also showed a marked improvement. In CS groups it was 24.6 and in CR it was 27.4. Statistical analysis showed a highly significant difference in favor of cruciate sacrificing prosthesis. Conclusions:Total Knee Arthroplasty in patients in whom posterior cruciate ligament was sacrificed was found to have a better functional outcome as compared to the retaining group, which can be mainly attributed to the persistence of flexion deformity in cruciate retaining group. In Indian scenario where knee replacement is done at a late stage of osteoarthritis, sacrificing the contracted posterior cruciate ligament has better outcomes as compared to retaining it.
Athletes who participate in extreme or adrenaline sports accept a certain level of risk of injury. These injuries range in severity from minor abrasions and overuse injuries to fatal and catastrophic. An individual athlete determines an acceptable level of risk within a respective sport. As clinicians, our roles range from emergency medical care in the field or a clinic setting to preseason prevention programs and training. This chapter will focus on the injury prevention and training. The demands vary from sport to sport. For example, backcountry skiing and snowboarding will have obvious varied requirements than mountaineering or climbing. Due to this, preventative measures will be broken down into the following: skiing/snowboarding, climbing/mountaineering, and mountain biking.
This study was conducted to determine whether differences exist in the beliefs of Austrian versus United States mountain runners regarding the potential for downhill running to lead to joint damage in later years. Research design involved statistical analysis of quantitative research gathered by survey form at mountain races in each country, and qualitative research via personal comments obtained from interviews with these runners. The survey form was designed to exclude situations involving muscle damage and delayed onset muscle soreness and, instead, to focus on joint damage. The information was gathered by a short survey form using statements and the Lickert scale administered to race registrants at mountain races in Austria and in the US Rocky Mountains. These responses were then subjected to univariate F-tests of the five dependent variables from the survey form. Statistically significant differences were found in beliefs, with the Austrians more strongly believing that downhill running can lead to joint damage than did the US mountain runners. Further research is indicated to determine which belief is more accurate.
The patellofemoral pain syndrome is of high socioeconomic relevance as it most frequently occurs in young working patients. As its etiology is often unknown there is no standard treatment protocol. Several studies analyzed the different causes of patellofemoral pain and their different therapies. Static problems (pes planovalgus, instabilities, leg length differences) or chronic overuse of the knee extensor mechanism have to be identified and treated.
After exclusion of intra-articular pathologies, the treatment of patellofemoral pain syndrome begins with conservative management. Stretching of the flexor and extensor muscles and training of the quadriceps muscle are the main approaches. If conservative treatment fails and patellofemoral pain persists, there are several surgical procedures for realignment of the patella in the trochlear groove and reduction of the patellofemoral pressure.
Overweight patients exhibit chronic mechanical overuse of the patellofemoral joint. This leads to a higher rate of cartilage degeneration and problems at the inserting tendons and stabilizing tissues.
Estimates of knee joint loadings were calculated for 12 normal subjects from kinematic and kinetic measures obtained during both level and downhill walking. The maximum tibiofemoral compressive force reached an average load of 3.9 times body-weight (BW) for level walking and 8 times BW for downhill walking, in each instance during the early stance phase. Muscle forces contributed 80% of the maximum bone-on-bone force during downhill walking and 70% during level walking whereas the ground reaction forces contributed only 20% and 30% respectively. Most total knee designs provide a tibiofemoral contact area of 100 to 300 mm2. The yield point of these polyethylene inlays will therefore be exceeded with each step during downhill walking. Future evaluation of total knee designs should be based on a tibiofemoral joint load of 3.5 times BW at 20 degrees knee flexion, 8 times BW at 40 degrees and 6 times BW at 60 degrees.
The patellofemoral pain syndrome is of high socioeconomic relevance as it most frequently occurs in young working patients. As its etiology is often unknown there is no standard treatment protocol. Several studies analyzed the different causes of patellofemoral pain and their different therapies. Static problems (pes planovalgus, instabilities, leg length differences) or chronic overuse of the knee extensor mechanism have to be identified and treated. After exclusion of intra-articular pathologies, the treatment of patellofemoral pain syndrome begins with conservative management. Stretching of the flexor and extensor muscles and training of the quadriceps muscle are the main approaches. If conservative treatment fails and patellofemoral pain persists, there are several surgical procedures for realignment of the patella in the trochlear groove and reduction of the patellofemoral pressure. Overweight patients exhibit chronic mechanical overuse of the patellofemoral joint. This leads to a higher rate of cartilage degeneration and problems at the inserting tendons and stabilizing tissues.
A series of in vitro patella damage tests were developed using a knee simulator to investigate electron-beam-irradiated and -melted ultra-high molecular weight polyethylene and conventional ultra-high molecular weight polyethylene at the patellofemoral articulation. Three different simulations were created: (i) normal gait with optimal component alignment, (ii) stair climbing with optimal component alignment, and (iii) stair climbing with 4 degrees of femoral component internal rotation to simulate a component malalignment condition. In the last two simulations, all patellae were artificially aged. In normal gait, the unaged conventional and highly crosslinked patellae demonstrated similar behavior. In both stair climbing tests, unlike the aged highly crosslinked components, the aged conventional patellae developed cracks by 2 million cycles. These results demonstrate the potential advantage of highly crosslinked polyethylene for the patella.
ResearchGate has not been able to resolve any references for this publication.