Knee Adduction Moment Research Articles

Peak knee joint moments accurately predict medial and lateral knee contact forces in patients with valgus malalignment

Compressive knee joint contact force during walking is thought to be related to initiation and progression of knee osteoarthritis. However, joint loading is often evaluated with surrogate measures, like the external knee adduction moment, due to the complexity of computing joint contact forces. Statistical models have shown promising correlations between medial knee joint contact forces and knee adduction moments in particularly in individuals with knee osteoarthritis or after total knee replacements (R2 = 0.44–0.60). The purpose of this study was to evaluate how accurately model-based predictions of peak medial and lateral knee joint contact forces during walking could be estimated by linear mixed-effects models including joint moments for children and adolescents with and without valgus malalignment. Peak knee joint moments were strongly correlated (R2 > 0.85, p < 0.001) with both peak medial and lateral knee joint contact forces. The knee flexion and adduction moments were significant covariates in the models, strengthening the understanding of the statistical relationship between both moments and medial and lateral knee joint contact forces. In the future, these models could be used to evaluate peak knee joint contact forces from musculoskeletal simulations using peak joint moments from motion capture software, obviating the need for time-consuming musculoskeletal simulations.

Cumulative knee adduction moment during jogging causes temporary medial meniscus extrusion in healthy volunteers.

The cumulative knee adduction moment (KAM) is a key parameter evaluated for the prevention of overload knee injuries on the medial compartment. Medial meniscus extrusion (MME), typical in hoop dysfunctions, is a measure for the cumulative mechanical stress in individual knees; however, its correlation with cumulative KAM is unknown. The aim of this study was to investigate the effect of temporary overload stress on MME and its correlation with cumulative KAM. Thirteen healthy asymptomatic volunteers (13 knees) were recruited for a cohort study (mean age, 23.1 ± 3.3years; males: n = 8). The cumulative KAM was calculated using a three-dimensional motion analysis system, in addition to the number of steps taken while jogging uphill or downhill. MME was evaluated using ultrasound performed in the standing position. The evaluations were performed four times: at baseline (T0), before and after (T1 and T2, respectively) jogging uphill or downhill, and 1day after (T3) jogging. Additionally, the Δ-value was calculated using the change of meniscus after efforts as the difference in MME between T1 and T2. The MME in T2 was significantly greater than those in T0 and T1. Conversely, the MME in T3 was significantly lesser than that in T2. No significant difference was found between those in T0 and T1, and T3. ΔMME exhibited a significant positive correlation with the cumulative KAM (r = 0.68, p = 0.01), but not for peak KAM. The temporary reaction of MME observed in ultrasound correlates with the cumulative stress of KAM.

Transverse plane gait variables are better predictors for knee adduction moment than CT-based measures of torsional deformities in children and adolescents

Transverse plane gait variables are better predictors for knee adduction moment than CT-based measures of torsional deformities in children and adolescents

Higher Association of Pelvis-Knee-Ankle Angle Compared With Hip-Knee-Ankle Angle With Knee Adduction Moment and Patient-Reported Outcomes After High Tibial Osteotomy

Background: High tibial osteotomy (HTO) reduces the load distribution of the medial compartment by modifying leg alignment. Knee adduction moment (KAM), a surrogate measure of dynamic loading in the knee joint, decreases after HTO. However, leg alignment does not fully account for KAM. Purpose: To assess the association between the pelvis-knee-ankle angle (PKA), a novel radiographic parameter reflecting leg alignment and pelvic width, and KAM and patient-reported outcomes after HTO. Study Design: Cross sectional study; Level of evidence, 3. Methods: PKA is the angle between the line from the midpoint of the anterior superior iliac spine to the center of the knee joint and the mechanical axis of the tibia. In this study, 54 patients with medial compartment knee osteoarthritis and varus alignment who underwent 3-dimensional gait analysis preoperatively and 2 years after medial open-wedge HTO were evaluated. The primary outcomes were hip-knee-ankle angle (HKA), PKA, KAM peaks, and Knee Society Score (KSS). Single and multivariate regression analysis including PKA and KAM peaks as well as other demographic and radiologic factors was performed. Results: HKA was weakly correlated with the first peak KAM (r = −0.33; P < .01) and second peak KAM (r = −0.27; P = .01) before HTO, but not significantly correlated after HTO. PKA was moderately correlated with the first peak KAM (r = 0.45; P < .01) and second peak KAM (r = 0.45; P < .01) before HTO and with the first peak KAM (r = 0.51; P < .01) and second peak KAM (r = 0.56; P < .01) after HTO. Multivariate linear regression revealed that postoperative PKA was still associated with the KAM peaks after HTO. Only postoperative PKA was correlated with the KSS satisfaction subscale (r = −0.30; P = .03). Conclusion: Although HKA was not correlated with KAM peaks after HTO, PKA was significantly correlated with KAM peaks in patients with varus knee osteoarthritis after HTO.

High tibiofemoral contact and muscle forces during gait are associated with radiographic knee OA progression over 3 years

BackgroundThe objective of this study was to investigate differences in tibiofemoral joint contact forces between individuals with moderate medial OA who exhibit radiographic knee OA progression within 3 years versus those who do not, and to understand the relationship between model-predicted contact forces and net external moments for this population. Methods27 individuals with moderate medial compartment knee OA underwent baseline instrumented gait analysis. OA progressors were defined as those who experienced at least a one grade increase in medial joint space narrowing at three years. An electromyography-driven musculoskeletal model was used to estimate muscle and tibiofemoral contact forces at baseline, which were compared between progressors and non-progressors using t-tests. ResultsSeven individuals experienced radiographic OA progression by 3 years. Progressors walked with significantly higher peaks of medial and total tibiofemoral contact forces, and higher impulse of medial contact forces. Significant and high correlations were found between: first peaks of medial and total contact forces with first peak of the knee adduction moment (R2 = 0.74; R2 = 0.59); second peaks of medial and total knee contact forces with second peaks of knee adduction and flexion moments (R2 = 0.71; R2 = 0.68); medial knee contact force impulse with knee adduction moment impulse (R2 = 0.76). ConclusionsHigher tibiofemoral joint contact forces during walking were associated with three-year radiographic knee OA progression based on medial joint space narrowing. These results support the need for strategies that reduce compressive knee contact forces through the reduction of adduction and flexion moments during walking.

Evaluation of the Effect of Knee Unloader Orthoses, Lateral Wedge Insoles, and Ankle Foot Orthoses on Pain, Function, and Knee Adduction Moment in Subjects with Medial Compartment Knee Osteoarthritis: A Literature Review

ABSTRACT Introduction Osteoarthritis (OA) is a destructive joint disease and a major cause of pain in the elderly. The use of supportive orthoses including valgus knee brace, lateral wedged insole, and ankle-foot orthosis (AFO) is a common treatment for these people. The purpose of this review of the literature is to evaluate the effect of orthoses on pain, function, and adduction moment (AM) of individuals with medial knee OA. Method The search was conducted among articles published from 2010 to 2021 in bibliographic online databases including ISI Web of Science, PubMed, Scopus, and Google Scholar. The potential titles and abstracts were reviewed based on the study inclusion criteria. All randomized controlled trial (RCT) studies on the effectiveness of valgus knee brace, AFO, and lateral wedged insoles in subjects with medial knee OA were reviewed. The search terms were OA, medial knee osteoarthritis, medial joint arthritis, unloader knee brace, valgus knee brace, knee sleeve, lateral wedge insole, AFO, ankle-foot orthosis, function, pain, alignment, kinetic, kinematic, and AM. Result Forty-two articles were reviewed to determine the current research process. Thirteen studies evaluated the effect of lateral wedge insole on pain, function, and AM in subjects with medial compartment knee OA. Ten studies evaluated unloader knee braces. Nine studies evaluated unloader knee brace compared with lateral wedge insole, three studies evaluated AFO, and seven studies examined the combination of knee braces and lateral wedge insoles on pain, function, and AM. Conclusion All three orthoses in short-term follow-up reduced the AM in subjects with medial knee OA. Lateral wedge insoles did not support pain reduction in studies. The results of this study showed that knee braces may have a more lasting effect on the knee joint in the long run than lateral wedge insoles. Although the number of studies that evaluated the effect of AFOs on outcomes of subjects with knee OA is low, this intervention was found to be effective in relieving pain and reducing AM. Clinical Relevance In clinical studies, clinical relevance in patients with medial knee OA, orthoses effectively reduced external knee AM and pain sensation during daily activities. Thus, use of orthoses effectively supports conservative treatment in medial knee OA.

IMU and Smartphone Camera Fusion for Knee Adduction and Knee Flexion Moment Estimation During Walking

Wearable sensing and computer vision could move biomechanics from specialized laboratories to natural environments, but better algorithms are needed to extract meaningful outcomes from these emerging modalities. In this article, we present new models for estimating biomechanical outcomes—the knee adduction moment (KAM) and knee flexion moment (KFM)—from fusion of smartphone cameras and wearable inertial measurement units (IMUs) among young healthy nonobese males. A deep learning model was developed to extract features, fuse multimodal data, and estimate KAM and KFM. Walking data from 17 subjects were recorded with eight IMUs and two smartphone cameras. The model that used IMU-camera fusion was significantly more accurate than those using IMUs or cameras alone. The root-mean-square errors of the fusion model were 0.49 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\%\;\mathbf {BW}\cdot \mathbf {BH}$</tex-math></inline-formula> for KAM and 0.66 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\%\;\mathbf {BW}\cdot \mathbf {BH}$</tex-math></inline-formula> for KFM estimation, which are lower than clinically significant thresholds. With larger and more diverse data, this model could enable assessment of knee moments in clinics and homes.

Prediction of knee adduction moment using innovative instrumented insole and deep learning neural networks in healthy female individuals

BackgroundThe knee adduction moment, a biomechanical risk factor of knee osteoarthritis, is typically measured in a gait laboratory with expensive equipment and inverse dynamics modeling software. We aimed to develop a framework for a portable knee adduction moment estimation for healthy female individuals using deep learning neural networks and custom instrumented insole and evaluated its accuracy compared to the standard inverse dynamics approach. MethodsFeed-forward, convolutional, and recurrent neural networks were applied to the data extracted from five piezo-resistive force sensors attached to the insole of a shoe. ResultsAll models predicted knee adduction moment variables during walking with high correlation coefficients, r > 0.72, and low root mean squared errors (RMSE), ranging from 0.5% to 1.2%. The convolutional neural network is the most accurate predictor of average knee adduction moment (r = 0.96; RMSE = 0.5%) followed by the recurrent and feed-forward neural networks. ConclusionThese findings and the methods presented in the current study are expected to facilitate a cost-effective clinical analysis of knee adduction moment for healthy female individuals and to facilitate future research on prediction of other biomechanical risk factors using similar methods.

Clinically-accessible and laboratory-derived predictors of biomechanical response to standalone and supported lateral wedge insoles in people with knee osteoarthritis

BackgroundLateral wedge insoles (both standalone and those incorporating individualized arch support) have been frequently studied for the effects on knee joint loading and pain in people with knee osteoarthritis. It has been shown that many people who use these insoles do not obtain the intended biomechanical effect, and thus may not experience a clinical benefit. The ability to identify biomechanical responders to lateral wedge insoles before research or clinical intervention is an important objective for efficient resource use and optimizing patient outcomes. The purpose of our exploratory, hypothesis-generating study was to provide an initial assessment of variables that are associated with the biomechanical response to lateral wedge insoles in people with knee osteoarthritis.MethodsWe collected a number of demographic (age, sex, body mass index, foot posture), clinical (knee pain, foot pain, radiographic disease severity), and walking-related (speed, knee alignment, frontal plane subtalar movement, and foot rotation) outcomes from 53 individuals with painful, radiographically-confirmed knee osteoarthritis. The walking-related outcomes were obtained using equipment both from the research laboratory and the clinical setting. We used logistic regression to generate predictive models to determine candidate variables associated with a reduction in the knee adduction moment during walking – a surrogate for tibiofemoral load distribution, and a known biomechanical risk factor for osteoarthritis progression – with the use of standalone and arch-supported lateral wedge insoles. Three different response thresholds (2%, 6%, and 10% reductions in the knee adduction moment) were used.ResultsIn general, biomechanical responders were those who walked faster, were female, had less varus alignment, and had less severe radiographic severity. Findings were similar between the standalone and arch-supported lateral wedge insoles, as well as between models using the laboratory-derived or clinically-available measures of walking performance.ConclusionsOur hypothesis-generating study provides valuable information that will inform future research into the efficient and effective use of lateral wedge insoles in the conservative management of knee osteoarthritis.

The biomechanical effects of insoles with different cushioning on the knee joints of people with different body mass index grades.

Background: Enhancing knee protection for individuals who are overweight and obese is crucial. Cushioning insoles may improve knee biomechanics and play a significant protective role. However, the impact of insoles with varying cushioning properties on knee joints in individuals with different body mass index (BMI) categories remains unknown. Our aim was to investigate the biomechanical effects of insoles with different cushioning properties on knee joints across different BMI grades. Methods: Gravity-driven impact tests were used to characterize the cushioning properties of three types of Artificial Cartilage Foam (ACF18, 28, and 38) and ethylene-vinyl acetate (EVA) insoles. Knee joint sagittal, coronal, and vertical axis angles and moments were collected from healthy-weight (BMI 18.5-23.9kg/m2, n = 15), overweight (BMI 24.0-27.9kg/m2, n = 16), and obese (BMI ≥28.0kg/m2, n = 15) individuals randomly assigned four different insoles during a drop jump. The Kruskal-Wallis test and mixed model repeated measures analysis of variance were used to compare differences among cushioning and biomechanical data across various insoles, respectively. Results: ACF showed higher cushioning than EVA, and ACF38 was the highest among the three types of ACF (all p < 0.001). During the drop jump, the knee flexion angles and moments of the ACF insoles were lower than those of the EVA insoles, the knee adduction angles of the ACF18 and ACF28 insoles were lower than those of the EVA insoles, and ACF18 insoles increased the first cushion time (all p < 0.05) for all participants in whom biomechanical variables demonstrated no interactions between insoles and BMI. Regarding the BMI-dependent biomechanical variables, compared with the EVA insoles, ACF28 insoles decreased the knee flexion angle and ACF38 insoles decreased the knee adduction and rotation moment in the healthy-weight group; ACF18 insoles decreased the knee flexion angle and ACF38 insoles decreased the knee moment in the overweight group; ACF28 insoles decreased the knee flexion and adduction moment, and ACF38 insoles decreased the knee flexion angle and rotation moment in the obese group (all p < 0.05). Conclusion: Insoles with higher cushioning properties could improve knee biomechanics and provide better knee joint protection in people across different BMI ranges.

Effect of foot progression angle alteration on medial-lateral center of pressure position during single-leg standing.

[Purpose] This study aimed to investigate the effect of altering the foot progression angle (FPA) on the center of pressure (COP) position during single-leg standing. [Participants and Methods] Fifteen healthy adult males participated. The participants performed single-leg standing on the left leg in three different FPA conditions, namely toe-in, neutral, and toe-out, in which the FPA was set to 0°, 10°, and 20°, respectively. The COP positions and pelvis angles were measured using a 3D motion analysis system, and each measurement value among the three conditions was compared. [Results] The medial-lateral COP position differed among conditions in the coordinate system based on the laboratory condition but did not differ in the coordinate system based on the longitudinal axis of the foot segment. Moreover, no changes were observed in pelvis angles that would affect COP position. [Conclusion] Altering the FPA does not change the medial-lateral position of the COP during single-leg standing. Here we show that COP displacement based on the laboratory coordinate system is involved in the mechanism-linking alteration of FPA and changes in knee adduction moment.

Native knee kinematics is not reproduced after sensor guided cruciates substituting total knee arthroplasty

PurposeGait analysis was used to evaluate knee kinematics in patients who underwent successful primary total knee arthroplasty (TKA) using two modern bi-cruciate substituting designs. The knee joint was balanced intraoperatively using real-time sensor technology, developed to provide dynamic feedback regarding stability and tibiofemoral load. The authors hypothesized that major differences exist in gait parameters between healthy controls and post-TKA patients.MethodsTen patients who underwent successful TKA using bi-cruciate substituting designs were evaluated at a minimum of 9 months postoperatively using three-dimensional knee kinematic analysis; a multi-camera optoelectronic system and a force platform were used. Sensor-extracted kinematic data included knee flexion angle at heel-strike (KFH), peak midstance knee flexion angle (MSKFA), maximum and minimum knee adduction angle (KAA) and knee rotational angle at heel-strike. Multiple gait analysis data from the study group were compared to a group of ten healthy controls who were matched by age, sex and BMI. Clinical outcome in the TKA group was also measured using the Knee injury and Osteoarthritis Outcome Score (KOOS).ResultsClinically, at final follow-up, a statistically significant difference in pain, general symptoms, and activities of daily living was seen between the groups. From a gait analysis standpoint, TKA patients had significantly less rotation at heel strike (p = 0.04), lower late stance peak extension moments (p = 0.02), and less Knee Adduction Angle excursion during swing phase (p = 0.04) compared to the control group. No statistically significant difference was observed for knee flexion angle at heel strike, knee adduction moment, or peak knee flexion moment between the groups.ConclusionsModern bi-cruciate substituting TKA designs failed to reproduce normal knee kinematics. The lack of full knee extension during the stance phase, absence of the “screw-home mechanism” typical of an ACL functioning knee, and the reduced fluctuation in knee adduction angle during the swing phase still represent major proprioceptive and muscular recruitment differences between normal and replaced knees.

Walking with shorter stride length could improve knee kinetics of patients with medial knee osteoarthritis

Walking with a shorter stride length (SL) was recently proposed for gait retraining in medial knee osteoarthritis; however it was never assessed in this patient population. This study tested the hypothesis that shortening SL while maintaining walking speed reduces knee adduction (KAM) and flexion (KFM) moments in patients with medial knee osteoarthritis. Walking trials with normal SL and SL reduced by 0.10 m and 0.15 m were recorded for 15 patients (10 men, 55.5 ± 8.7 years old, 24.6 ± 3.0 kg/m2). SL was modified using an augmented reality system displaying target footprints on the floor. Repeated one-way ANOVAs and post-hoc paired t-tests were performed to compare gait measures between normal and reduced SL. The individual effects of SL reduction were analyzed using descriptive statistics. Group analysis indicated significant decreases in KAM impulse with both SL reductions (p < 0.05). No systematic change was observed in the first peaks KAM and KFM when walking with reduced SL (p > 0.05). Individually, 33 % of the patients decreased the peak KAM, whereas 20 % decreased the KAM impulse. Among these patients with a decrease in peak KAM or in KAM impulse, 0 % and 33 % had a simultaneous increase in peak KFM, respectively. In conclusion, this study showed that SL shortening can decrease kinetic measures associated with the progression of medial knee osteoarthritis in some patients, demonstrating the importance of considering SL modifications on an individual basis. While further research is necessary, notably regarding dose-response relationships and long-term effects, these findings are particularly encouraging because SL reductions could be easily integrated into rehabilitation protocols.

CARTILAGE THICKNESS, SUBCHONDRAL BONE MINERAL DENSITY, AND AMBULATORY LOADING ARE CORRELATED IN NON-OSTEOARTHRITIC FEMORAL CONDYLES

A few studies have reported correlations between structural and functional parameters in healthy knees, and sometimes alterations of these correlations with OA. These observations suggested a new concept where knee OA could be related to a maladaptation between joint features. However, studies analyzing multiple features from different domains simultaneously are missing, which makes it difficult to fully understand the importance of relationships in maintaining joint homeostasis and their role in the development of OA. To assess the correlations among cartilage thickness (CTh), subchondral bone mineral density (sBMD), and ambulatory loading in non-OA femoral condyles. As commonly done, ambulatory loading was quantified using the peak knee adduction moment during walking (pKAM), which is a proxy for the distribution of load between medial and lateral compartments. To analyze comparable data, CTh and sBMD were expressed as medial-to-lateral (M/L) ratios. Therefore, this study tested the hypothesis that CTh M/L ratios, sBMD M/L ratios, and pKAM are positively correlated in non-OA femoral condyles. This study analyzed a subgroup of 48 young (25.7 ± 4.8 years; 22 males) asymptomatic volunteers with healthy knees enrolled in the HIPPA-compliant IRB-approved Lausanne Knee Study. This study aims at characterizing the structure and function of the knee, with a particular emphasis on the relationships among knee features The study protocol included clinical evaluation, radiographic imaging (weight-bearing Schuss and lateral radiographs of both knees), CT imaging (calibrated by a solid calcium hydroxyapatite-based bone mineral reference phantom) and 3T MRI of one randomly selected knee. 3D gait recordings were performed using a 16-camera motion capture system and force plates. CTh was obtained by manually segmenting the cartilage and bone on the DESS images, building 3D mesh models of bone and cartilage, and calculating the distance between the models. sBMD was obtained by registering the bone models from the DESS segmentation to the CT images and calculating the average CT intensity in the 3 mm of bone adjacent to cartilage. Mean CTh and sBMD were then calculated for six common regions of interest (ROIs) in the medial and lateral condyles and expressed as M/L ratios. pKAM was obtained following a standard inverse dynamics procedure applied to the marker-based motion capture and force plate recordings. Data processing was done using in-house software and algorithms previously validated. The relationship among CTh M/L ratios, sBMD M/L ratios and pKAM were assessed using Pearson correlation, with an α-level set a priori at 5%. All statistically significant correlations were positive, indicating larger CTh M/L ratios in knees with larger sBMD M/L ratios and larger pKAM, and vice versa. Specifically, CTh and sBMD M/L ratios were correlated in 5 of the 6 ROIs (0.31 ≤ r ≤ 0.53; 0.001 ≤ p ≤ 0.035), CTh M/L ratios in 4 ROIs were correlated with pKAM (0.29 ≤ r ≤ 0.33; 0.021 ≤ p ≤ 0.047), and sBMD M/L ratio in one ROI was correlated with pKAM (r = 0.31; p = 0.032). The hypothesis was supported, confirming the idea that structural and mechanical features of the knee are positively correlated, or adapted, in non-OA knees. This first study to show correlations among bone, cartilage, and mechanical loading provided insight into the functioning of the joint and underlined the potential of evaluating knee health based on relationships among features rather than on individual features in isolation. The analyses in this study will be extended to OA knees in future studies in order to determine the alterations of the relationships between knee features with OA.

Gait biomechanical analysis of unaffected knee before and 6 months after total knee arthroplasty

Abstract Study aim: This study aimed to compare gait biomechanical data on the unaffected side before and six months after total knee arthroplasty (TKA) and determine the postoperative changes in medial knee loading on the unaffected side. Material and methods: Three-dimensional gait analysis was performed on 19 female patients who had underwent TKA. Gait parameters were extracted at each time point using the maximum value of the backward (braking phase) and forward components (propulsion phase) of the ground reaction force on the unaffected side, while the knee adduction moment impulse (KAM impulse) was used as an index of medial knee loading. The pre – and post-TKA values of these parameters were compared. The relationship between KAM impulse and gait biomechanical factors on the unaffected side was examined using partial correlation analysis with gait speed as a control factor. Results: KAM impulse was not significantly different on the unaffected side compared to preoperatively. In the braking phase, there were significant differences in hip adduction moment (p = 0.033) and ankle dorsiflexion moment (p = 0.013), and hip flexion angle (p=0.011) in the propulsive phase. The relationship between KAM impulse and gait biomechanical factors on the unaffected side showed a positive correlation between KAM impulse and knee adduction angle (braking phase, propulsion phase; r = 0.671, 0.689) and KAM (braking phase, propulsion phase; r = 0.715, 0.745). Conclusions: There was no significant difference in KAM impulse on the unaffected side before and after TKA, suggesting that TKA did not influence medial knee loading increase on the unaffected side even six months post-TKA.

The Comparison between Pharmaceutical Method and Changes in Speed of Patients with Knee Osteoarthritis

Knee osteoarthritis is the most common degenerative bone and joint disease in the middle-aged and elderly. Here, we compared the diverse formulations of sports intensity and pharmaceutical selection for knee osteoarthritis patients. In this study, we compared and analyzed the differences and characteristics of lower limb joint kinematics, dynamics and muscle contraction function of knee osteoarthritis patients when walking at different speeds and the ones taking pharmaceutical selection including oral non-steroidal antiinflammatory drugs as well as topical capsaicin, so as to explore the impact of walking speed and drugs on the walking ability of knee osteoarthritis patients. 16 patients with left knee osteoarthritis and 16 patients with right knee osteoarthritis were selected and were grouped for different walking speed; 8 subjects were given oral non-steroidal anti-inflammatory drugs and 8 subjects were given topical capsaicin. Kistler threedimensional dynamometer, Noraxon surface electromyography and Qualisys infrared three-dimensional motion analysis were used to record the gait parameters. Compared with walking at low speed, normal walking speed significantly increased the knee maximum flexion angle. For dynamic parameters, the lowest value of first peak knee adduction moment presented in normal speed patients and there was also significant difference between groups for hip flexion torque (p=0.014), the first peak of knee adduction torque (p=0.043) and knee flexion torque (p=0.040). For the electromyographic parameters, in the early period of support, the speed of the lower extremity rectus femoris (p=0.001), anterior tibial muscle (p=0.016), lateral femur muscle (p=0.040) and the average amplitude of electromyography were not equal for distinct groups. We found that the outcome of kinematics parameters for oral non-steroidal anti-inflammatory drug was greatly higher than topical capsaicin. The research conclusion will provide important scientific basis and theoretical support for knee osteoarthritis population to conduct walking exercise scientifically and reasonably.

Managing Genu Varum in Adolescents to Reduce Risks of Progression to Knee Osteoarthrosis

Introduction: Genu varum is not uncommon in adolescents. Managing the condition to reduce its progression may decrease the prevalence of incident knee osteoarthrosis in adulthood. The present review examines studies on risk factors contributing to the progression of genu varum and associated with the degeneration of the medial tibiofemoral joint. We proposed approaches to decrease the magnitude of genu varum and external knee adduction moment, to reduce the incidence of knee osteoarthrosis in the aged population. Methods and Materials: Literature searches were conducted in Pubmed, Embase, and Cochrane Systematic Reviews, using keywords individually and in combinations. We excluded papers on pathological genu varum, tibia vara, Blount disease, nutritional rickets, imaging, and surgery and included only articles on genu varum involving children and young adults. Reference lists of the included papers were also screened manually for additional references. Results and Discussion: Search results showed that many children with physiologic genu varum are deficient or insufficient in vitamin D. High-impact exercises in late children and adolescents promote genu varum. In contrast, therapeutic exercises reduce the magnitude of genu varum in young adults with postural bowlegs. Lateral wedge insoles decrease the external knee adduction moment. We proposed to check the serum vitamin D level of children and adolescents with genu varum. Growing children with genu varum should be advised to reduce the frequency of performing high-impact exercises. Adolescents with genu varum should strengthen the external hip rotators and use lateral wedged insoles.

Delivering Load-Modifying Gait Retraining Interventions via Telehealth in People With Medial Knee Osteoarthritis: A Pilot Randomized Placebo-Controlled Clinical Trial.

We aimed to investigate the effects of delivering 3 gait retraining interventions (toe-in, toe-out, and placebo gait) on proxy measures of medial knee load (early- and late-stance peak knee adduction moment [KAM], KAM impulse, and varus thrust) in people with knee osteoarthritis, using a hybrid model of face-to-face and telehealth-delivered sessions over 5 months. This was an originally planned 3-arm randomized placebo-controlled clinical trial. However, during the 2021 COVID-19 outbreak and lockdown in Sydney, Australia, the study became a pilot randomized controlled trial with the remainder of interventions delivered via telehealth. Nine individuals with symptomatic medial knee osteoarthritis were allocated to receive either a toe-in, toe-out, or posture re-education (placebo) gait retraining intervention. Primary outcomes of early- and late-stance peak KAM, KAM impulse, and varus thrust were assessed at baseline and follow-up. Eight participants returned for their follow-up gait assessment. Participants in both active intervention groups (toe-in and toe-out) achieved foot progression angle changes at follow-up. Overall, knee biomechanics in the placebo group did not change at follow-up. It is possible to achieve biomechanical changes in individuals with medial knee osteoarthritis when delivering gait retraining interventions via a hybrid model of face-to-face and telehealth.

Potential biomechanical risk factors on developing lead knee osteoarthritis in the golf swing

The load on the lead knee joint during a golf swing is greater than that observed during gait. However, current evidence regarding golf swing biomechanics for risks associated with knee osteoarthritis (OA) is limited. Therefore, this study investigated golf swing styles associated with knee adduction and abduction moments, which are considered to be crucial loading regions of the medial and lateral compartments of knee OA, respectively. Thirteen professional male golfers performed five shots using a 5-iron club, and their swings were recorded using a motion capture system with two force platforms for the feet. A regression analysis was performed to calculate the correlation coefficients between the peak knee adduction and abduction moments of the lead leg and varus/valgus angle, toe-out angle, stance width, weight transfer, and shoulder sway. Swinging with a narrower stance width at address (r = − 0.62, p = 0.02) with more weight shift (r = 0.66, p = 0.014) and shoulder sway (r = 0.79, p = 0.001) towards the target during the downswing were associated with a higher peak knee adduction of the lead leg, whereas a greater valgus angle at address (r = 0.60, p = 0.03) was associated with a higher peak knee abduction of the lead leg. Based on these findings, we anticipate future research to support postural changes, particularly a wider stance width and restricted shoulder sway for golfers who are classified to be at high risk of developing medial compartment knee OA, as well as a lower valgus (tibial medial tilt) angle at address for those classified to be at high risk of developing lateral compartment knee OA.

Relationship Between Knee Biomechanics and Pain in People With Knee Osteoarthritis: A Systematic Review and Meta-Analysis.

Our primary aim was to determine the cross-sectional relationship between knee biomechanics during gait and pain in people with medial knee osteoarthritis. Our secondary aim was to evaluate differences in knee biomechanics between symptomatic and asymptomatic participants with medial knee osteoarthritis. Four online databases were searched from inception to July 2021. Eligible studies included people with medial/nonspecific knee osteoarthritis and a reported relationship between knee biomechanics during gait and pain or biomechanics of symptomatic and asymptomatic participants. Two reviewers independently extracted data and evaluated risk of bias. Random-effects meta-analyses were performed when three or more studies reported the same biomechanical variable for pooling (knee adduction moment [KAM], KAM impulse, varus thrust, and peak knee flexion moment [KFM]). Forty studies were included. Methodological quality ranged from 4 to 9/10. Forty-seven unique biomechanical variables were reported. For the KAM, there was no correlation with pain for peak values pooled (early stance and overall) (r=0.00, 95% confidence interval [95% CI]: -0.12, 0.11, k=16), a small negative correlation for early stance peak alone (r = -0.09, 95% CI -0.18, -0.002, k=12), and a medium positive correlation for the overall peak during stance (r=0.30, 95% CI 0.17, 0.42, k=4). Metaregression identified that body mass index moderated the peak KAM-pain relationship (P < 0.001). KAM impulse had a small positive correlation with pain (r=0.23, 95% CI 0.04, 0.40, k=5), and people with varus thrust had 3.84 greater odds of reporting pain compared with people without (95% CI 1.72, 8.53, k=3). Meta-analyses for the peak KFM and pain correlation and secondary aim were nonsignificant. Some knee gait biomechanics were associated with pain in this cohort. Longitudinal studies are required to determine causality.