# Background and Purpose Isometric strength testing is an important tool for detecting deficits in injured populations and monitoring strength changes during rehabilitation and training. However, it is unclear whether strength measurements obtained from low-cost, inline force sensors match measurements from large, expensive, lab-based dynamometers. Therefore, the purpose of this study was to investigate agreement in maximum voluntary isometric knee extension torque measurements between a lab-based dynamometer, a low-cost wireless inline force sensor, and a wired inline force sensor. # Design Prospective cross-sectional study # Setting Laboratory # Methods Fourteen healthy adult participants (age >18 years) were recruited from the university community using posters, email, and social media advertisements. Peak isometric knee extension torque was measured for two repetitions at each of three knee angles (90°, 45° and 15°) using a lab-based dynamometer (Humac, CSMI Medical Solutions, USA). Then, all six trials were repeated while simultaneously recording strength using a low-cost wireless inline force sensor (Tindeq, Trondheim, Norway) and a wired inline force sensor wired (MLP, Transducer Techniques, CA, USA). Peak electromyography (EMG) magnitude was recorded for knee extensors and flexors, and electrical stimulation was used to quantify the level of voluntary activation (VA) for knee extensors. Agreement between torque measurement systems was assessed using Pearson’s Correlation (r), Interclass Correlation Coefficients (ICC3,1, absolute agreement), Minimum Detectable Change, and Bland-Altman Limits of Agreement (LOA). Additionally, peak torque was compared at each knee angle using a repeated measures ANOVA, and peak EMG outputs were compared using paired t-tests. # Results Fourteen participants completed the study (3 male, 11 female; 26 ± 8.97 years; 1.71 ± 0.11 m; 66.75 ± 15.9 kg). The mean (95% CI) difference in torque between Tindeq and Humac dynamometers was 0.16 Nm/kg (−0.07 to 0.26 Nm/kg) at a knee angle of 15 degrees, −0.02 Nm/kg (−0.19 to 0.14 Nm/kg) at 45 degrees, and −0.10 Nm/kg (−0.32 to 0.13 Nm/kg) at 90 degrees. Bland-Altman LOA were −0.86 to 0.67 Nm/kg at 15 degrees, −0.60 to 0.55 Nm/kg at 45 degrees, and −0.86 to 0.67 Nm/kg at 90 degrees. Bias and LOA were similar for the MLP device. All participants achieved >90% VA. Results were more similar between Tindeq and MLP inline force sensors (r = 1.0, ICC3,1 = 0.94-1.00) than between inline force sensors and the Humac device (r <0.81, ICC3,1 = 0.37-0.80). # Conclusions Although sample size was small and only a single testing session was performed, the Tindeq device showed small measurement bias, underestimating the Humac torque by less than 0.1 Nm at 45 and 90 degrees. However, relatively large LOA indicated that individual measurement errors could exceed 25%. Low-cost wireless force sensors (e.g. Tindeq) show promise for clinical use, but individual measurements should be interpreted with caution. # Level of Evidence 2 (measurement agreement and validity study)

Background: The Mercer Universal Prosthesis (MUP), designed with a default “neutral” (vertical) socket alignment, was developed to simplify transtibial prosthetic fitting, reduce labor costs, and improve access to prosthetic care in low-resource settings. Methods: This present longitudinal study evaluated biomechanical and functional outcomes at baseline, 6 months, and 12 months in 20 transtibial amputees fitted with the MUP. Results: Functional outcomes, assessed using the SF-36, showed significant improvement in overall health scores at 12 months (p < 0.001), while physical function and energy/fatigue domains remained unchanged (p = 0.686 and p = 0.211, respectively). Biomechanically, sagittal kinematics, measured using inertial motion capture, revealed significant limb × time interactions for hip flexion, knee flexion, and ankle plantarflexion. At 6 months, maximum hip flexion (−7°, p = 0.008) and knee flexion (−11°, p = 0.005) of the prosthetic limb were decreased versus baseline. At 12 months, the only observed difference was increased maximum ankle plantarflexion of the intact limb (+5° vs. baseline, p = 0.016). Muscle effort, quantified via the integral of EMG throughout the gait cycle, did not differ significantly between prosthetic and intact limbs across time points. Gait symmetry index (GSI) scores for hip, knee, and ankle range of motion trended toward gradual improvement but without statistical significance (p > 0.05). Conclusions: The MUP performance was maintained over 12 months, with stable biomechanical performance and meaningful quality-of-life gains. These findings support its potential as a cost-effective solution to expand prosthetic accessibility in low- and middle-income countries.

Background: Wearable inertial measurement units (IMoCAPs) are increasingly used in clinical gait analysis due to their portability and ability to capture data outside laboratory settings; however, validation across operating conditions is essential. Objective: To evaluate the concurrent validity and reliability of the Noraxon Ultium™ IMU system against a Vicon optical motion capture (OMC) system for lower-limb kinematics during walking across different speeds and time intervals. Methods: Ten healthy adults performed overground walking at slow, normal, and fast self-selected speeds. Kinematics were recorded simultaneously using both systems. Discrete variables (Max, Min, ROM) were analyzed using three-factor repeated-measures ANOVA (Device × Speed × Time, p < 0.05). Agreement was assessed using Bland-Altman analysis, RMSE, and ICC (3,1), and waveform differences were evaluated using Statistical Parametric Mapping (SPM). Results: Time effects were minimal across all planes. Sagittal-plane kinematics showed strong agreement, with small biases (<3°), low RMSE (≤2.5°), and moderate reliability (ICC = 0.65-0.74). Both systems detected increased hip and knee motion with speed, although Device × Speed interactions indicated greater IMoCAP underestimation at higher speeds. Frontal-plane agreement was poor to moderate (RMSE: 1-3°, ICC: 0.42-0.74). Transverse-plane kinematics demonstrated the largest discrepancies (RMSE up to 6-7°, ICC: 0.17-0.26), particularly for hip rotation. SPM revealed significant waveform differences across all planes. Conclusions: The Noraxon Ultium™ IMU provides valid sagittal-plane gait assessment, moderate frontal-plane agreement, and limited reliability for transverse-plane kinematics, requiring cautious interpretation at higher speeds.

Standardizing socket design and maintaining a default socket alignment in transtibial prostheses are innovations that aim to simplify fitting procedures and reduce prosthetic service costs, particularly in low-income countries. Objectives: This study evaluated the Mercer Universal Prosthesis (MUP) with a standardized “neutral alignment” against custom-made conventional prostheses (CVPs). Methods: Twenty transtibial amputees (n = 20) completed gait assessments using their CVP and immediately after fitting with an MUP. Temporal–spatial and sagittal plane kinematics (hip, knee, and ankle angles) were analyzed, along with a gait symmetry index. Results: the MUP group reported a significant difference between the prosthetic and the intact limb for both hip and knee kinematics (p < 0.05), but there was no change in the CVP group. When compared with the sound limb in the MUP group, post hoc analysis showed that both hip flexion and the hip range of motion (ROM) in the MUP limb significantly increased by 5.7° and 7.3° (p = 0.002 and p < 0.001, respectively). Spatial and temporal gait parameters were comparable between the MUP and CVP groups, and gait symmetry showed no significant differences. The CVP showed greater symmetry in terms of hip (19%, p = 0.012) and knee flexion (8%, p = 0.026) compared to the MUP, while the MUP had higher plantarflexion symmetry (24.4%, p = 0.013). Conclusions: Immediately post fitting, MUP improved joint mobility in the prosthetic limb, potentially enhancing kinematics. While short-term benefits are evident, further research is needed to assess long-term gait adaptation and quality of life impacts.

Adhesive-augmented sternal fixation (AASF) has been investigated as an alternative to the clinical standard of cerclage wires; however, previous studies have focused on a full adhesive layer across the sternal midline, which acts as a barrier to bone healing. This study used a human cadaveric model to investigate if partial coverage AASF used in combination with wired fixation could provide adequate stability. Median sternotomies were performed on fifteen human cadaveric sterna. Three groups (n = 5) with varying adhesive coverage (50 %, 62.5 %, 75 %) of the sternal midline and traditional wiring were investigated. Cyclic lateral distraction loading of 10 N to 100 N was applied at 50 N/s. Every 30 cycles, the maximum load was increased by 100 N to a maximum of 500 N. Displacement was measured using transducers spanning the transection line at the manubrium, body, and xiphoid. Mean maximum total displacement (MMTD) for all groups was significantly below 2 mm (p < 0.001) with 1.49 mm ± 0.82 mm, 0.97 mm ± 0. 55 mm, and 0.67 mm ± 0.65 mm in the 50 %, 62.5 %, and 75 % groups respectively. MMTD in the 50 % group was significantly greater than MMTD in the 62.5 % and 75 % groups. AASF improved stability as coverage of the sternal surface with adhesive increased. Partial coverage of the sternal midline with adhesive may provide similar rigidity to a full layer while enabling earlier sternal ossification at the transection line compared to wiring alone.

Dynamic loads have short and long-term effects in the rehabilitation of lower limb joints. However, an effective exercise program for lower limb rehabilitation has been debated for a long time. Cycling ergometers were instrumented and used as a tool to mechanically load the lower limbs and track the joint mechano-physiological response in rehabilitation programs. Current cycling ergometers apply symmetrical loading to the limbs, which may not reflect the actual load-bearing capacity of each limb, as in Parkinson's and Multiple Sclerosis diseases. Therefore, the present study aimed to develop a new cycling ergometer capable of applying asymmetric loads to the limbs and validate its function using human tests. The instrumented force sensor and crank position sensing system recorded the kinetics and kinematics of pedaling. This information was used to apply an asymmetric assistive torque only to the target leg using an electric motor. The performance of the proposed cycling ergometer was studied during a cycling task at three different intensities. It was shown that the proposed device reduced the pedaling force of the target leg by 19% to 40%, depending on the exercise intensity. This reduction in pedal force caused a significant reduction in the muscle activity of the target leg (p < 0.001), without affecting the muscle activity of the non-target leg. These results demonstrated that the proposed cycling ergometer device is capable of applying asymmetric loading to lower limbs, and thus has the potential to improve the outcome of exercise interventions in patients with asymmetric function in lower limbs.

Lower limb tissue stiffness is contingent on various factors, including location, tissue composition, loading rates, and the geometry of the indenting object. Previous studies demonstrated that tissue stiffness varies greatly between individuals and between locations on an individual. Additionally, some studies have shown that activation of underlying muscle tissue increases bulk soft tissue stiffness. Yet, few studies have simultaneously considered both location and activation; this could be particularly important for measuring and predicting the function of devices such as prostheses and exoskeletons that interact with limbs at various locations during dynamic movement. In the present study, a custom handheld indentation device was used to explore changes in bulk leg tissue stiffness at rest and during isometric contractions. The indentation force-displacement curves were modelled using a Hertz model. At each level of activation (active/inactive), the shank had dramatically (∼150%) greater tissue stiffness than the thigh (p < 0.001). However, results suggested location independence for stiffness ratio (active/inactive, p = 0.42); for either location, stiffness was approximately 2x greater for active vs inactive muscle. These results should be considered during the development of biomechanical models to simulate human tissue indentation stiffness across a range of activation states and locations.

Machine learning-based activity and gait phase recognition algorithms are used in powered motion assistive devices to inform control of motorized components. The objective of this study was to develop a supervised multiclass classifier to simultaneously detect activity and gait phase (stance, swing) in real-world walking, stair ascent, and stair descent using inertial measurement data from the thigh and shank. The intended use of this algorithm was for control of a motion assistive device local to the knee. Using data from 80 participants, two decision trees and five long short-term memory (LSTM) models that each used different feature sets were initially tested and evaluated using a novel performance metric: proportion of perfectly classified strides (PPCS). Based on the PPCS of these initial models, five additional posthoc LSTM models were tested. Separate models were developed to classify (i) both activity and gait phase simultaneously (one model predicting six states), and (ii) activity-specific models (three individual binary classifiers predicting stance/swing phases). The superior activity-specific model had an accuracy of 98.0% and PPCS of 55.7%. The superior six-phase model used filtered inertial measurement data as its features and a median filter on its predictions and had an accuracy of 92.1% and PPCS of 22.9%. Pooling stance and swing phases from all activities and treating this model as a binary classifier, this model had an accuracy of 97.1%, which may be acceptable for real-world lower limb exoskeleton control if only stance and swing gait phases must be detected. Keywords: machine learning, deep learning, inertial measurement unit, activity recognition, gait.

Purpose The fused filament fabrication (FFF) process is an additive manufacturing technique used in engineering design. The mechanical properties of parts manufactured by FFF are influenced by the printing parameters. The mechanical properties of rigid thermoplastics for FFF are well defined, while thermoplastic elastomers (TPE) are uncommonly investigated. The purpose of this paper is to investigate the influence of extruder temperature, bed temperature and printing speed on the mechanical properties of a thermoplastic elastomer. Design/methodology/approach Regression models predicting mechanical properties as a function of extruder temperature, bed temperature and printing speed were developed. Tensile specimens were tested according to ASTM D638. A 3×3 full factorial analysis, consisting of 81 experiments and 27 printing conditions was performed, and models were developed in Minitab. Tensile tests verifying the models were conducted at two selected printing conditions to assess predictive capability. Findings Each mechanical property was significantly affected by at least two of the investigated FFF parameters, where printing speed and extruder temperature terms influenced all mechanical properties ( p < 0.05). Notably, tensile modulus could be increased by 21%, from 200 to 244 MPa. Verification prints exhibited properties within 10% of the predictions. Not all properties could be maximized together, emphasizing the importance of understanding FFF parameter effects on mechanical properties when making design decisions. Originality/value This work developed a model to assess FFF parameter influence on mechanical properties of a previously unstudied thermoplastic elastomer and made property predictions within 10% accuracy.

When runners impact the ground, they experience a sudden peak ground reaction force (GRF), which may be up to 4x greater than their bodyweight. Increased GRF impact peak magnitude has been associated with lower limb injuries in runners. Yet, shoe midsoles are capable of cushioning the impact between the runner and the ground to reduce GRF. It has been proposed that midsoles should be tunable with subject mass to minimize GRF and reduce risk of injury. Auxetic metamaterials, structures designed to achieve negative Poisson's ratios, demonstrate superior impact properties and are highly tunable. Recently, auxetic structures have been introduced in footwear, but their effects on GRF are not documented in literature. This work investigates the viability of a three-dimensional auxetic impact structure with a tunable force plateau as a midsole through mass-spring-damper simulation. An mass-spring-damper model was used to perform 315 simulations considering combinations of seven subject masses (45-90 kg), 15 auxetic plateau forces (72-1080 N), and three auxetic damping conditions (450, 725, and 1000 Ns/m) and regression analysis was used to determine their influence on GRF impact peak, energy, instantaneous, and average loading rate. Simulations showed that tuning auxetic plateau force and damping based on subject mass may reduce GRF impact and loading rate versus simulated conventional midsoles. Auxetic plateau force and damping conditions of 450 Ns/m and similar to 1 bodyweight (BW), respectively, minimized peak impact GRF. This work demonstrates the need for tunable auxetic midsoles and may inform future work involving midsole testing.

Background: The 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 rela-tionship between model-predicted contact forces and net external moments for this pop-ulation.Methods: 27 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.Results: Seven 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).Conclusions: Higher 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.(c) 2023 Elsevier B.V. All rights reserved.

Objective: Off-loader knee braces have traditionally focused on redistributing loads away from either the medial or lateral tibiofemoral (TF) compartments. In this article, we study the potential of a novel “tricompartment unloader” (TCU) knee brace intended to simultaneously unload both the patellofemoral (PF) and TF joints during knee flexion. Three different models of the TCU brace are evaluated for their potential to unload the knee joint.Methods: A sagittal plane model of the knee was used to compute PF and TF contact forces, patellar and quadriceps tendon forces, and forces in the anterior and posterior cruciate ligaments during a deep knee bend (DKB) test using motion analysis data from eight participants. Forces were computed for the observed (no brace) and simulated braced conditions. A sensitivity and validity analysis was conducted to determine the valid output range for the model, and Statistical Parameter Mapping was used to quantify the effectual region of the different TCU brace models.Results: PF and TF joint force calculations were valid between ~0 and 100 degrees of flexion. All three simulated brace models significantly (p < 0.001) reduced predicted knee joint loads (by 30–50%) across all structures, at knee flexion angles >~30 degrees during DKB.Conclusions: The TCU brace is predicted to reduce PF and TF knee joint contact loads during weight-bearing activity requiring knee flexion angles between 30 and 100 degrees; this effect may be clinically beneficial for pain reduction or rehabilitation from common knee injuries or joint disorders. Future work is needed to assess the range of possible clinical and prophylactic benefits of the TCU brace.

To evaluate the effect of the braced arm-to-thigh technique (BATT) (versus self-selected techniques) on three-dimensional trunk kinematics and spinal loads for three common activities of daily living (ADLs) simulated in the laboratory: weeding (gardening), reaching for an object in a low cupboard, and car egress using the two-legs out technique. Ten young healthy males performed each task using a self-selected technique, and then using the BATT. The pulling action of weeding was simulated using a magnet placed on a steel plate. Cupboard and car egress tasks were simulated using custom apparatus representing the dimensions of a kitchen cabinet and a medium-sized Australian car, respectively. Three-dimensional trunk kinematics and L4/L5 spinal loads were estimated using the Lifting Full-Body OpenSim model and compared between techniques. Paired t-tests were used to compare peak values between methods (self-selected vs BATT). The BATT significantly reduced peak extension moments (13–51%), and both compression (27–45%) and shear forces (31–62%) at L4/L5, compared to self-selected techniques for all three tasks (p < 0.05). Lateral bending angles increased with the BATT for weeding and cupboard tasks, but these changes were expected as the BATT inherently introduces asymmetric trunk motion. The BATT substantially reduced L4/L5 extension moments, and L4/L5 compression and shear forces, compared to self-selected methods, for three ADLs, in a small cohort of ten young healthy males without prior history of back pain. These study findings can be used to inform safe procedures for these three ADLs, as the results are considered representative of a mature population.

Osteoarthritis knee braces require large brace-leg interface forces to stabilize and unload the joint during weight bearing. Actively removing support while the user is in a non-weight-bearing state could improve the comfort of the brace but requires the timing of weight-bearing states to be known. This study presents two artificial neural networks (ANNs) for predicting time-to-next heelstrike during walking using only data from two accelerometers placed on the thigh and shank. One ANN used teacher forcing and the other did not. Walking data were collected from 10 subjects and leave-one-subject-out cross-validation was used to evaluate the performance of the two models. Input features for the ANNs included tibial and femoral accelerations, concatenated into one array. The teacher forcing ANN and the non-teacher forcing ANN performed equally well (RMSE = 0.23 +/- 0.13s for the non-teacher forcing ANN, RMSE = 0.27 +/- 0.08s for the teacher forcing ANN). The performances of the models were worse than those of previously published studies that predicted heelstrike events. Accelerations were insufficient for an ANN to predict time-to-next heelstrike during walking.

The Static Optimization (SO) solver in OpenSim estimates muscle activations and forces that only equilibrate applied moments. In this study, SO was enhanced through an open-access MATLAB interface, where calculated muscle activations can additionally satisfy crucial mechanical stability requirements. This Stability-Constrained SO (SCSO) is applicable to many OpenSim models and can potentially produce more biofidelic results than SO alone, especially when antagonistic muscle co-contraction is required to stabilize body joints. This hypothesis was tested using existing models and experimental data in the literature. Muscle activations were calculated by SO and SCSO for a spine model during two series of static trials (i.e. simulation 1 and 2), and also for a lower limb model (supplementary material 2). In simulation 1, symmetric and asymmetric flexion postures were compared, while in simulation 2, various external load heights were compared, where increases in load height did not change the external lumbar flexion moment, but necessitated higher EMG activations. During the tasks in simulation 1, the predicted muscle activations by SCSO demonstrated less average deviation from the EMG data (6.8% −7.5%) compared to those from SO (10.2%). In simulation 2, SO predicts constant muscle activations and forces, while SCSO predicts increases in the average activations of back and abdominal muscles that better match experimental data. Although the SCSO results are sensitive to some parameters (e.g. musculotendon stiffness), when considering the strategy of the central nervous system in distributing muscle forces and in activating antagonistic muscles, the assigned activations by SCSO are more biofidelic than SO.

There is currently no validated full-body lifting model publicly available on the OpenSim modelling platform to estimate spinal loads during lifting. In this study, the existing full-body-lumbar-spine model was adapted and validated for lifting motions to produce the lifting full-body model. Back muscle activations predicted by the model closely matched the measured erector spinae activation patterns. Model estimates of intradiscal pressures and in vivo measurements were strongly correlated. The same spine loading trends were observed for model estimates and reported vertebral body implant measurements. These results demonstrate the suitability of this model to evaluate changes in lumbar loading during lifting.

Despite the common use of one-handed lifting techniques for activities of daily living, these techniques have received little attention in the biomechanics literature. The braced arm-to-thigh technique (BATT) is a one-handed lifting method in which the dominant hand picks up objects, while the free hand braces the trunk on the ipsilateral thigh. The aim of this study was to compare the BATT to two-handed or unsupported one-handed lifting techniques with loads of 2 and 10 kg, by evaluating trunk motion and spine loading at L4/L5. Twenty healthy participants (30-70 years old) matched in age and sex to 18 participants with low back pain were recruited to the study. A three-axis load cell secured to the distal anterior thigh measured the bracing forces applied by the hand. The OpenSim Lifting Full-Body model was used to estimate trunk kinematics and spinal loading at L4/L5. Linear mixed-effects models were developed to compare trunk angles and L4/L5 moments and forces between lifting techniques. Trunk flexion angles were significantly reduced for the BATT lift compared to one-handed and two-handed stoop lifts (9-20%). However, the BATT also increased asymmetric trunk kinematics and moments at L4/L5. The BATT produced significantly lower moments (28-38%), and compressive (25-32%) and antero-posterior shear (25-45%) forces at L4/L5, compared to unsupported lifting techniques. Bracing the hand on the thigh to support the trunk can substantially reduce low back loading during lifting tasks of 2 to 10 kg. (C) 2019 Elsevier Ltd. All rights reserved.

BACKGROUND:Braces for medial knee osteoarthritis can reduce medial joint loads through a combination of three mechanisms: application of an external brace abduction moment, alteration of gait dynamics, and reduced activation of antagonistic muscles. Although the effect of knee bracing has been reported independently for each of these parameters, no previous study has quantified their relative contributions to reducing medial knee loads.METHODS:In this study, we used a detailed musculoskeletal model to investigate immediate changes in medial and lateral loads caused by two different knee braces: OA Assist and OA Adjuster 3 (DJO Global). Seventeen osteoarthritis subjects and eighteen healthy controls performed overground gait trials in unbraced and braced conditions.RESULTS:Across all subjects, bracing reduced medial loads by 0.1 to 0.3 times bodyweight (BW), or roughly 10%, and increased lateral loads by 0.03 to 0.2 BW. Changes in gait kinematics due to bracing were subtle, and had little effect on medial and lateral joint loads. The knee adduction moment was unaltered unless the brace moment was included in its computation. Only one muscle, biceps femoris, showed a significant change in EMG with bracing, but this did not contribute to altered peak medial contact loads.CONCLUSIONS:Knee braces reduced medial tibiofemoral loads primarily by applying a direct, and substantial, abduction moment to each subject's knee. To further enhance brace effectiveness, future brace designs should seek to enhance the magnitude of this unloader moment, and possibly exploit additional kinematic or neuromuscular gait modifications.

Valgus unloader knee braces are a conservative treatment option for medial compartment knee osteoarthritis (OA). These braces are designed to reduce painful, and potentially injurious compressive l...

Injuries to the anterior cruciate ligament (ACL) and menisci commonly lead to early onset osteoarthritis. Treatments that can restore normative cartilage loading patterns may mitigate the risk of osteoarthritis, though it is unclear whether such a goal is achievable through conservative rehabilitation. We used musculoskeletal simulation to predict cartilage and ligament loading patterns during walking in intact, ACL deficient, menisci deficient, and ACL-menisci deficient knees. Stochastic simulations with varying coordination strategies were then used to test whether neuromuscular control could be modulated to restore normative knee mechanics in the pathologic conditions. During early stance, a 3 mm increase in anterior tibial translation was predicted in the ACL deficient knee. Mean cartilage contact pressure increased by 18% and 24% on the medial and lateral plateaus, respectively, in the menisci deficient knee. Variations in neuromuscular coordination were insufficient to restore normative cartilage contact patterns in either the ACL or menisci deficient knees. Elevated cartilage contact pressures in the pathologic knees were observed in regions where cartilage wear patterns have previously been reported. These results suggest that altered cartilage tissue loading during gait may contribute to region-specific degeneration patterns, and that varying neuromuscular coordination in isolation is unlikely to restore normative knee mechanics.