Adduction Moment Research Articles

Is early trunk rotation really hazardous for shoulder biomechanics in baseball throwing?

Early trunk rotation (ETR), which is a unique kinematics of the trunk that occurs during baseball throwing, is thought to be related to shoulder injuries. Pelvic rotation is a confounder when studying the effects of trunk rotation on shoulder biomechanics. The purpose of this study was to understand the "pure" effects of trunk rotation on shoulder biomechanics, with pelvic rotation under control. Our hypotheses were as follows: (1) throwers with ETR have a different shoulder kinematics pattern compared with throwers without ETR; (2) throwers with ETR have a lower ball speed performance than do throwers without ETR; and (3) throwers with ETR have a greater value of shoulder forces and moments, which may increase risks of shoulder injury, than do throwers without ETR. Fifty-seven elite throwers were enrolled and divided into 2 groups (non-ETR and ETR) using an outdoor motion analysis. Several kinematics and kinetics parameters of the shoulder were analyzed and compared between the 2 groups. Ball velocity was faster in the non-ETR group (127 km/h) compared with the ETR group (120 km/h). The shoulders of throwers in the ETR group showed pathokinematics of "horizontal adduction lag" and "dropped elbow." The increases in maximal posterior force, inferior force, horizontal abduction moment, and vertical adduction moment were 9.2%, 13.6%, 21.3%, and 24.3%, respectively, in the shoulders of throwers in the ETR group. These results indicate that ETR may be hazardous for the throwing shoulder. With lower ball velocity and higher shoulder joint loading, ETR is not a proper pitching pattern for kinetic energy transfer. Improper pitching mechanics among baseball throwers, such as ETR, may result in higher shoulder joint loading and increased risk of shoulder injuries. When treating throwers with shoulder injuries, it is important not only to address shoulder anatomy and pathology but also to understand the possible pathomechanics and pathogenesis of the shoulder caused by ETR. Furthermore, special training programs focusing on trunk flexibility and core muscle strengthening should be implemented to prevent ETR and decrease the risk of shoulder injuries. Motion analysis is useful for the screening and early detection of improper pitching mechanics in throwers.

Knee osteoarthritis: A systematic Review on different Exercise therapy Interventions on K.A.M

Exercise therapy can be part of a conservative treatment plan for knee osteoarthritis. Knee adduction moments (KAMs) are thought to be reduced with exercise therapy. A large study looked at exercise therapy's effect on KAM and other physical factors in persons with knee osteoarthritis. Methods: Searches were performed on the following electronic databases: MEDLINE, Google Scholar, Cochrane Central, EMBASE, and OpenGrey. Study participants with knee osteoarthritis undergoing structured exercise therapy were randomized controlled trials. For every study, we conducted independent analyses to extract data and analyze the bias risks. We calculated the mean differences and 95% confidence intervals for each outcome. Results: In the three studies that involved 233 participants, there were no significant differences in KAMs between intervention and control groups. Two of the studies observed improvements in physical function after exercise therapy and one of them demonstrated significant reductions in pain. All three trials favor the intervention group in terms of muscle strength and torque. Conclusions: A change in knee adduction time was not associated with the therapeutic benefits of exercise therapy. Exercise therapy for knee osteoarthritis may not be effective if there is no momentary adduction. Dynamic joint loading may result from a shift in neuromuscular control after exercise therapy

Biomechanical Effect of Valgus Knee Braces on the Treatment of Medial Gonarthrosis: A Systematic Review.

Background Valgus braces are prescribed as a common conservative treatment option for patients with medial gonarthrosis to improve their quality of life. Many studies had reviewed the effects of the valgus braces on patients with medial gonarthrosis, while they mainly focused on the knee adduction moment (KAM), with less attention paid to other parameters such as spatiotemporal and morphological parameters. Objectives The purpose of this study was to review the effects of valgus braces on the spatiotemporal, kinematic/kinetic, morphological, and muscle parameters. Methods Based on the selected keywords, a survey of literatures was performed in Web of Science, PubMed, Scopus, and Google Scholar using the PRISMA methods, and the search period was established from January 2000 to March 2022. Results Thirty-four articles were included. According to the conclusion of these articles, the valgus brace can be used to relieve the symptoms of patients with medial gonarthrosis by decreasing the varus angle, decreasing the KAM, and redistributing the knee compartment loads. However, the effects of valgus braces on other biomechanical parameters (e.g., walking speed, cadence, joint angle, and joint space) had not reached a consensus. Conclusions The valgus knee brace can effectively relieve the symptoms of medial gonarthrosis through multiple mechanisms, while there is still some confusion about the effectiveness of the valgus brace on the other biomechanical parameters.

The effects of foot orthosis and low-dye tape on lower limb joint angles and moments during running in individuals with pes planus

BackgroundPes Planus or Flat feet is one of the most common lower limb abnormalities. When runners with this abnormality participate in recreational running, interventional therapies could help in pain alleviation and enhance performance. To determine the most effective treatment, however, a biomechanical examination of the effects of each treatment modality is required. Research questionThe aim of the present study was to investigate the effects of Foot Orthoses (FOs) and Low-Dye Tape (LDT) on lower limb joint angles and moments during running in individuals with pes planus. Methodskinematic and kinetic data of 20 young people with pes planus were measured during running in three conditions: (1) SHOD (2) with shoes and FOs (3) with shoes and LDT. One-way repeated measure ANOVA was used to investigate the impacts of the FOs and LDT on the lower limb joint angles and moments throughout the stance phase of the running cycle. ResultsThe results showed that FOs reduced ankle eversion compared to SHOD and LDT (P < 0.001) and decreased the dorsiflexion angle (P = 0.005) and the plantarflexor moment compared to the SHOD (P < 0.001). FOs increased knee adduction angle (P = 0.021) and knee external rotator moment (P < 0.001) compared to both conditions and increased knee extensor and abductor moments compared to SHOD (P < 0.001). At the hip joint, FOs only increased hip external rotation compared with the LDT condition (P = 0.031); and LDT increased hip extensor moment compared to SHOD and FOs (P = 0.037) and also increased hip adduction angle compared to SHOD (P = 0.037). SignificanceFOs with a medial wedge appears to increase the external knee adduction moment and knee adduction angles, which are risk factors for the development and progression of knee osteoarthritis. Further, usage of FOs seems to reduce the ankle joint role in propulsion as it impacts the ankle sagittal angles and moments.

Gait biomechanics phenotypes among total knee arthroplasty candidates by machine learning cluster analysis.

Knee osteoarthritis patient phenotyping is relevant to developing targeted treatments and assessing the treatment efficacy of total knee arthroplasty (TKA). This study aimed to identify clusters among TKA candidates based on demographic and knee mechanic features during gait, and compare gait changes between clusters postoperatively. TKA patients underwent 3D gait analysis 1-week pre (n = 134) and 1-year post-TKA (n = 105). Principal component analysis was applied to frontal and sagittal knee angle and moment waveforms, extracting major patterns of variability. Age, sex, body mass index, gait speed, and frontal and sagittal pre-TKA angle and moment PC scores previously identified as relevant to TKA outcomes were standardized (mean = 0, SD = 1, [134 × 15]). Multidimensional scaling and machine learning-based hierarchical clustering were applied. Final clusters were validated by examining intercluster differences pre-TKA and gait feature changes (PostPCscore - PrePCscore ) by k-way Χ2 and ANOVA tests. Four TKA candidate phenotypes yielded optimum clustering metrics, interpreted as higher and lower functioning clusters that were predominantly male and female. Higher functioning clusters pre-TKA (clusters 1 and 4) had more dynamic sagittal flexion moment (p < 0.001) and frontal plane adduction moment (p < 0.001) loading/un-loading patterns during stance. Post-TKA, higher functioning clusters demonstrated less knee mechanic improvements during gait (flexion angle p < 0.001; flexion moment p < 0.001).TKA candidates can be characterized by four clusters, predominately separated by sex and knee joint biomechanics. Post-TKA knee kinematics and kinetics improvements were cluster-specific; lower functioning clusters experienced more improvement. Cluster-based patient profiling may aid in triaging and developing OA management and surgical strategies meeting group-level function needs.

Predicting knee adduction moment response to gait retraining with minimal clinical data.

Knee osteoarthritis is a progressive disease mediated by high joint loads. Foot progression angle modifications that reduce the knee adduction moment (KAM), a surrogate of knee loading, have demonstrated efficacy in alleviating pain and improving function. Although changes to the foot progression angle are overall beneficial, KAM reductions are not consistent across patients. Moreover, customized interventions are time-consuming and require instrumentation not commonly available in the clinic. We present a regression model that uses minimal clinical data-a set of six features easily obtained in the clinic-to predict the extent of first peak KAM reduction after toe-in gait retraining. For such a model to generalize, the training data must be large and variable. Given the lack of large public datasets that contain different gaits for the same patient, we generated this dataset synthetically. Insights learned from a ground-truth dataset with both baseline and toe-in gait trials (N = 12) enabled the creation of a large (N = 138) synthetic dataset for training the predictive model. On a test set of data collected by a separate research group (N = 15), the first peak KAM reduction was predicted with a mean absolute error of 0.134% body weight * height (%BW*HT). This error is smaller than the standard deviation of the first peak KAM during baseline walking averaged across test subjects (0.306%BW*HT). This work demonstrates the feasibility of training predictive models with synthetic data and provides clinicians with a new tool to predict the outcome of patient-specific gait retraining without requiring gait lab instrumentation.

The dynamic characteristics of the center of pressure for toe-out gait: implications for footwear design

BackgroundToe-out gait is often used as a conservative technique to reduce knee adduction moment, which has been targeted to modify knee osteoarthritis progression. The center of pressure (COP) can not only be used to evaluate gait stability, but is also more reliable and practical than local plantar pressures as it does not depend on accurate foot zone divisions. However, to the authors’ knowledge, few study has reported the influence of the foot progression angle on the dynamic characteristics of the COP.Research questionThe aim of the study was to investigate the effects of the deliberately toe-out gait on the COP trajectory and stability during walking in healthy individuals.MethodsThirty healthy young adults were asked to walk along an 8-m walkway. A Footscan 1 m pressure plate was used to measure the center of pressure during walking.ResultsCompared to the normal gait, the COP of the toe-out gait shifted laterally during the initial contact phase, and shifted laterally and anteriorly during the forefoot contact phase. The mean anterior–posterior velocity of COP reduced by 0.109 m/s during the foot flat phase and the duration of the foot flat phase and forefoot push off phase increased by 4.5% and reduced by 7.0%, respectively.SignificanceCompared to the normal gait, the findings of this study suggest that biomechanical alteration of foot under our experimental conditions may decrease gait stability and increase forefoot load during toe-out walking. The situation may be improved by well-designed footwear or custom-made insole and the biomechanics analysis method can be used to test the efficacy of therapeutic footwear or insole for individuals with deliberately toe-out walking.Graphical

The impact of ankle-foot orthosis's plantarflexion resistance on knee adduction moment in people with chronic stroke.

An ankle-foot orthosis (AFO) is used to assist gait of people with chronic stroke. It is widely accepted that AFO's plantarflexion resistance affects sagittal knee moments during their gait. However, its effect on the coronal knee moment remains unclear. This study aimed to examine the effects of varying articulated AFO's plantarflexion resistance on knee adduction moment in people with chronic stroke. Ten people with chronic stroke participated in this study. Gait performance was measured using a Vicon 3-dimensional motion capture system and a Bertec split-belt instrumented treadmill. The participants walked on the treadmill wearing an articulated AFO whose plantarflexion resistance could be systematically adjusted. The ankle joints were set to four distinct levels of plantarflexion resistance (S1 < S2 < S3 < S4). The coronal ankle and knee joint moment, center of pressure, and ground reaction force were analyzed using Visual3D. The external knee adduction moment increased significantly ( P < .001) and the position of the center of pressure trajectory shifted significantly ( P = .003) in the medial direction as the plantarflexion resistance of the AFO was increased from the least resistive condition (S1) to the most resistive condition (S4). The maximum knee adduction moment (median [interquartile range]) was S1: 0.097 (-0.012 to 0.265) Nm/kg; S2: 0.136 (0.040 to 0.287) Nm/kg; S3: 0.160 (0.465 to 0.289) Nm/kg; and S4: 0.192 (0.080 to 0.288) Nm/kg. This study demonstrated that varying AFO's plantarflexion resistance altered the knee adduction moment, likely by altering the center of pressure trajectory while walking, in people with chronic stroke.

Comparison of the knee joint reaction force between individuals with and without acute anterior cruciate ligament rupture during walking

BackgroundAnterior cruciate ligament plays a significant role in knee joint stability. It is claimed that the incidence of knee osteoarthritis increases in individuals with anterior cruciate ligament (ACL) rupture. The aim of this study was to evaluate the knee joints reaction force in ACL rupture group compared to normal subjects.MethodFifteen patients with acute ACL rupture and 15 healthy subjects participated in this study. The ground reaction force (GRF) and kinematic data were collected at a sampling rate of 120 Hz during level-ground walking. Spatiotemporal parameters, joint angles, muscle forces and moments, and joint reaction force (JRF) of lower extremity were analyzed by OpenSIM software.ResultsThe hip, knee and ankle joints reaction force at loading response and push-off intervals of the stance phase during walking was significantly higher in individuals with ACL rupture compared to healthy controls (p value < 0.05). Walking velocity (p value < 0.001), knee (p value = 0.065) and ankle (p value = 0.001) range of motion in the sagittal plane were significantly lower in the patients with ACL rupture compared to healthy subjects. The mean value of vertical GRF in the mid-stance, the peak of the hip adduction moment in loading response and push-off phases, the hip abductor, knee flexor and vastus intermedius part of quadriceps muscle forces were significantly higher compared to healthy subjects (p < 0.05) while vastus medialis and vastus lateralis produced significantly lower force (p < 0.001).ConclusionsBased on results of this study, lower limb JRF was higher in those with ACL rupture compared to healthy subjects may be due to the compensatory mechanisms used by this group of subjects. An increase in knee JRF in patients with ACL rupture may be the reason for the high incidence of knee OA.

Infraspinatus Muscle Fiber Moment Arms During Abduction: A Biomechanical Comparison of Values for Intact Rotator Cuff, Supraspinatus Tear, Superior Capsular Reconstruction, and Reverse Total Shoulder Arthroplasty.

Background:Lines of action of the superior, middle, and inferior infraspinatus muscle fibers work together to produce moment arms that change throughout abduction in an intact shoulder, after a supraspinatus tear, and after superior capsular reconstruction (SCR) and reverse total shoulder arthroplasty (rTSA).Purpose:To use moment arm values to indicate the efficacy of SCR and rTSA to restore infraspinatus function during shoulder abduction.Study Design:Descriptive laboratory study.Methods:A total of 5 human cadaveric shoulders placed in a testing apparatus were each actively abducted (0°-90°) under the following 4 conditions: intact, complete supraspinatus tear, SCR, and rTSA. The 3-dimensional coordinates of points were tracked along the origin and insertion of the superior, middle, and inferior infraspinatus fibers during abduction. Moment arm values were calculated using the origin-insertion method to determine abduction contribution of infraspinatus fiber sections. Analysis of variance and post hoc Tukey testing were used to compare differences in moment arms between the 4 conditions and between fiber sections.Results:In the intact condition, the superior infraspinatus fibers had an abduction moment that decreased with elevation until shifting to adduction. Conversely, the middle and inferior fibers had an adduction moment that turned to abduction (mean moment arm values from 0° to 90°: inferior, from –5.9 to 19.4 mm; middle, from –4.7 to 15.9 mm; superior, from 5.6 to –5.1 mm; P < .05). After a supraspinatus tear, superior fibers lacked any torque, and inferior and middle fibers lost adduction potential (inferior, from 4.8 to 14.0 mm; middle, from –0.2 to 9.6 mm; superior, from 1.0 to 0.7 mm; P < .05). SCR restored the initial superior fiber abduction moment (5.6 mm at 0°; P < .05); middle and inferior fibers had some restoration but were weaker than intact fibers. Loss of abduction moment in all fibers was seen with rTSA (inferior, from –9.6 to –1.6 mm; middle, from –10.5 to –3.6 mm; superior, from –1.7 to –4.6 mm; P < .05).Conclusion:Infraspinatus fiber groups had different and inverse moment arms during scapular plane elevation. SCR most closely resembled the intact shoulder, whereas rTSA transformed the infraspinatus into an adductor.Clinical Relevance:These results support the efficacy of SCR at restoring biomechanical muscle function and suggest that the changes in moment arms for each fiber group be considered when choosing treatment modalities and rehabilitation protocols after rotator cuff tear.

Sexual Dimorphism Impact on the Ground Reaction Force Acting on the Mediolateral Direction During Level Walking: Hip Abductor Muscle Biomechanics and Its Correlation to GRF Moment Arm.

The female pelvis morphology represents an evolved compensation between two opposing needs: a broad pelvis enough to deliver a sizeable brained offspring while remaining narrow enough to allow for effective bipedal gait. The precise expectation of hip abductor force generation is critical in anthropological studies and experimental practice of human stride mechanics. Hip implants and surgical procedures for hip anatomy reconstruction are based on the static single-leg stance paradigm. The current work investigated the impact of sexual dimorphism on the ground reaction force (GRF) acting on the mediolateral direction during level walking, emphasizing the difference in hip abductor muscle biomechanics and its correlation to ground reaction force moment arm, R. The ground reaction force in the mediolateral direction, hip abduction and adduction moments during the gait cycle and ground reaction force moment arm, R were measured. The current study concludes that the male individuals exhibit significantly higher mass-specific mediolateral ground reaction force during level walking. In contrast, hip abductor moments/kg body weight, medialization of the trochanter, R, and hip coronal were more significant in female individuals. We conclude that increased abductor moment and medialization of the greater trochanter will increase R, hip coronal and decrease abductor moment arm, r, in female individuals, affecting the effective mechanical advantage (EMA) of hip abductors in single-limb stance during level walking.

Modulation of internal tissue stresses of the knee via control of variable-stiffness properties in a 3D-printed footwear: A combined experimental and finite element analysis

Aims: Therapeutic footwear with variable-stiffness properties has been shown to be effective in reducing the external knee adduction moment. However, the exact changes of internal tissue stresses following intervention with variable-stiffness footwear remains unknown. The objective of this study is to construct a finite element model of the foot-ankle-knee complex to investigate the therapeutic efficacy of the variable-stiffness footwear in modulating internal knee joint stress distributions. Methods: Footwear with lateral-to-medial stiffness ratio of 1.00, 1.33, 1.49 and 1.77 were designed and 3D-printed as lattice structures at different porosity levels. A three-dimensional finite element model of the foot-ankle-knee complex was constructed with cartilage-meniscus structures characterized by magnetic resonance imaging. Ground reaction forces and muscular loads estimated from gait experiments with 3D-printed variable-stiffness footwear were used to drive the model, and effects of footwear intervention with four stiffness ratios on tibiofemoral joint loads were evaluated during the simulated instant in gait. Results: Compared with the constant-stiffness design, the variable-stiffness footwear reached a maximum reduction of the first peak knee adduction moment up to 17.1%. As the lateral-to-medial stiffness ratio increases, the peak stresses at the meniscus in the medial compartment of the knee were reduced by 5.0%, 7.9%, and 16.4%, respectively. The stress-modifying effects were less pronounced for the lateral compartment of the knee. Conclusion: The variable-stiffness footwear design produced stress relieving to the cartilage and meniscus structures, and the fact that lower stiffness ratio had reached significantly less effects, suggesting a favourable stress-relief effect should consider footwear with a higher lateral-to-medial stiffness ratio.

Variable Stiffness Shoes for Knee Osteoarthritis: An Evaluation of 3-Dimensional Gait Mechanics and Medial Joint Contact Forces.

The study aim was to quantify the impact of a commercially available variable stiffness shoe (VSS) on 3-dimensional ankle, knee, and hip mechanics and estimated knee contact forces compared with a control shoe. Fourteen participants (10females) with knee osteoarthritis completed gait analysis after providing informed consent. Shoe conditions tested were control shoe (New Balance MW411v2) and VSS (Abeo SMART3400). An OpenSim musculoskeletal model with static optimization was used to estimate knee contact forces. There were no differences in joint kinematics or in the knee adduction or flexion moments (P = .06; P = .2). There were increases in the knee internal and external rotation (P = .02; P = .03) and hip adduction and internal rotation moments for VSS versus control (P = .03; P = .02). The estimated contact forces were not different between shoes (total P = .3, medial P = .1, and lateral P = .8), but contact force changes were correlated with changes in the knee adduction moment (medial r2 = .61; P < .007). High variability in knee flexion moment changes and increases in the internal rotation moment combined with small decreases in the knee adduction moment did not lead to decreases in estimated contact forces. These results suggest that evaluation of VSS using only the knee adduction moment may not adequately capture its impact on osteoarthritis.

Analysis of Lower Limb Joint Kinetics With Increasing Running Speed

Purpose: Due to the paucity of information regarding the lower limb biomechanics in running at slow speed, as well as the concentration of most previous studies on a single movement plane, this study aimed to investigate lower limb joint kinetics with increasing running speed. Methods: Twenty-eight runners were asked to stay on the treadmill at a bent velocity which was incrementally increased to 2.5 m/s, 3.5 m/s, and 4.5 m/s speeds. The three-dimensional joint moment and sagittal mechanical muscle power of the lower limb were calculated during the stance phase of running. Repeated measures analysis of variance (ANOVA) with Bonferroni post hoc test was used to examine the variables during running at various speeds. Results: The results showed that at the hip joint in the frontal plane, an adduction moment developed in the middle of the stance phase, and the highest peak adduction moment was obvious at the highest speed condition (4.5 m/s). Also, the time elapsed to peak in the highest speed condition was less than the others. In the transverse plane, although the 3.5 m/s-speed condition experienced the maximum external rotation peak moment, the 4.5 m/s-condition speed reached the internal status earlier than the two other speeds. In the sagittal plane, the highest speed condition showed the highest extension and flexion moments. Conclusion: Increasing running speed in runners leads to more kinetic output and mechanical power gradient.

MOVEMENT STARTEGIES ADOPTED BY INDIVIDUALS WITH MEDIAL KNEE OA IN RESPONSE TO PRESSURE-BASED AUDITORY FEEDBACK GAIT RERAINING

Purpose: Structural progression of medial knee osteoarthritis (OA) is associated with an increased knee adduction moment (KAM), a surrogate measure of the compartmental knee loads. The KAM is thus a target for mechanical intervention. Based on real-time pressure data and individualized training thresholds, the use of plantar pressure-based auditory feedback to shift weight medially was found to reduce the KAM in individuals with medial knee OA. However, its potential mechanisms remain unclear. Thus, this study aimed to elucidate movement strategies adopted by individuals with medial knee OA in response to pressure-based feedback gait retraining and compare movement strategies of substantial and partial responders of the intervention.

TOE-IN AND TOE-OUT GAIT RETRAINING FOR PEOPLE WITH MEDIAL KNEE OSTEOARTHRITIS: A PILOT RANDOMISED CLINICAL TRIAL

Purpose: Gait retraining has the potential to offload the medial tibiofemoral compartment to potentially reduce pain and slow osteoarthritis (OA) progression. Altering the foot progression angle (FPA), by toeing-in or toeing-out has demonstrated immediate proportional loading effects on indices of the knee adduction moment (KAM), a valid and reliable proxy measure of load, and a confirmed risk factor of disease progression. Previous randomised controlled trials (RCTs) have independently assessed either toe-in or toe-out gait, and it remains unknown which intervention is most achievable and their effects on proxy measures of medial knee load have not been directly compared.

NOVEL ‘APP’ AND WEARABLE INSOLE BASED REMOTE GAIT RETRAINING SHOW POTENTIAL TO ALTER GAIT MECHANICS TWO YEARS AFTER ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION

Purpose: Anterior cruciate ligament (ACL) injury substantially increases the risk for developing post-traumatic osteoarthritis (PTOA). While ACL reconstruction (ACLR) surgery is successful at stabilizing the knee, abnormal gait mechanics may develop and persist, establishing altered loading conditions that contribute to the development of OA. Increased knee adduction moment (KAM) in individuals 2 years following ACLR has been associated with increased cartilage matrix degeneration and reduced patient reported outcomes (PRO).

EFFECTS OF STEP WIDTH MODIFICATIONS ON KNEE KINETICS OF PATIENTS WITH MEDIAL KNEE OSTEOARTHRITIS WALKING WITH A DECREASED FOOT PROGRESSION ANGLE

Purpose: Gait retraining strategies are being developed worldwide to improve the mechanical loading of knee joints with medial osteoarthritis (OA). A dual kinetic change (DKC), aimed to decrease the peak knee adduction moment (pKAM) by at least 10% without increasing the peak knee flexion moment (pKFM), is particularly sought in this case. Interesting results have been obtained by instructing the patients to modify their footprint parameters, particularly reducing the foot progression angle (FPA), a modification also known as toeing-in, and more recently, by modifying step-width (SW).

ESTIMATION OF KNEE ADDUCTION MOMENT USING A SINGLE INERTIAL MEASUREMENT UNIT AND DEEP LEARNING

Purpose: Knee adduction moment (KAM) during gait is an index of medial joint loads of the knee, and have been used to help to identify the tipping point between a healthy knee and an at-risk/early osteoarthritis (OA) knee, and to intervene before further degradation occurs. To measure KAM, motion capture system and gait laboratory is required, and this fact limits to evaluate OA patients in clinic or hospital. Several systems have been developed that used inertial measurement units (IMUs) to capture joint motion, although those systems are not capable to evaluate ground reaction force and joint moments such as KAM.

IS REMOTE ACTIVE FEEDBACK GAIT RETRAINING COMPARABLE TO IN-PERSON RETRAINING 2 YEARS POST ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION?

Purpose: Anterior cruciate ligament (ACL) tear greatly increases the risk of osteoarthritis, a leading cause of chronic pain and disability. At 2 years post ACLR, altered knee mechanics have been associated with structural changes and longitudinal patient-reported outcomes (PROs). Specifically, increased knee adduction moment (KAM) correlated with cartilage deep tissue matrix degeneration, and greater KAM and flexion moment (KFM) predicted worse PROs in 8 years. In-person laboratory based active feedback gait retraining to produce medial weight shift under the foot has been shown to reduce KAM without increasing KFM in healthy and osteoarthritic knees.