Biomechanical Symmetry Research Articles

Association Between Pediatric International Knee Documentation Committee (Pedi-Ikdc) Score and Sagittal Knee Biomechanical Testing Following Anterior Cruciate Ligament Reconstruction

OBJECTIVE: to compare the Pediatric International Knee Documentation Committee (Pedi-IKDC) scores with sagittal knee kinematics and kinetics during the vertical drop jump test in pediatric athletes who had undergone primary unilateral anterior cruciate ligament reconstruction (ACLR), and determine if the two measures captured overlapping aspects of knee recovery. DESIGN: Retrospective Cohort Study METHODS: Seventy pediatric athletes who recently underwent ACLR completed biomechanical testing and the Pedi-IKDC survey. Limb symmetry for peak knee flexion angle (PKF), peak external knee flexion moment (PEKFM), and integral of power absorption (IPA) were evaluated and compared to Pedi-IKDC score using multivariate linear regressions controlling for time since surgery. Inter-knee symmetry was calculated using a limb symmetry index (LSI) by dividing the scores of the injured knee by the scores of the uninjured knee and multiplying by 100. RESULTS: There was a statistically significant positive relationship between Pedi-IKDC and LSI in PKF (R2=0.163, p=0.001) PEKFM (R2=0.067, p=0.033), and IPA (R2=0.087, p=0.014), indicating that higher Pedi-IKDC scores were associated with greater biomechanical symmetry when controlled for time. There were weak and significant positive relationships between time since surgery and PEKFM (R2=0.172, p<0.001) and IPA (R2=0.255, p<0.001) indicating improved biomechanical testing the further along from surgery, but there was no statistical significance between time since surgery and Pedi-IKDC or PKF. CONCLUSION: Pedi-IKDC and drop jump biomechanics were weakly related but mainly captured different aspects of recovery after ACLR. They can be considered as complementary tools when evaluating patients post-ACLR.

Evaluating Gait with Force Sensing Insoles 6 Months after Anterior Cruciate Ligament Reconstruction: An Autograft Comparison.

Aberrant knee mechanics during gait 6 months after anterior cruciate ligament reconstruction (ACLR) are associated with markers of knee cartilage degeneration. The purpose of this study was to compare loading during walking gait in QT, bone-patellar tendon-bone (BPTB), and hamstring tendon (HT) autograft patients 6 months post-ACLR using loadsol single sensor insoles, and to evaluate associations between loading and patient reported outcomes. 72 patients (13-40 years) who underwent unilateral, primary ACLR with BPTB, QT, or HT autograft completed treadmill gait assessment, the International Knee Documentation Committee (IKDC) survey and the ACL-Return to Sport after Injury (ACL-RSI) survey 6 ± 1 months post-ACLR. Ground reaction forces were collected using loadsols. Limb symmetry indices (LSI) for peak impact force (PIF), loading response instantaneous loading rate (ILR), and loading response average loading rate (ALR) were compared between groups using separate ANCOVAs. Survey scores were compared between groups using one-way ANOVAs. The relationships between IKDC, ACL-RSI, and LSIs were compared using Pearson's product moment correlation coefficients. There were no significant differences between graft sources for LSI in PIF, ILR, ALR, nor impulse. Patient-reported knee function was significantly different between graft source groups with the BPTB group reporting the highest IKDC scores; however, there was no significant difference between groups for ACL-RSI score. There were no significant associations between IKDC score, ACL-RSI score, and biomechanical symmetry among any of the graft source groups. Autograft type does not influence PIF, ILR, ALR, or impulse during walking 6 months post-ACLR. Limb symmetry during gait is not strongly associated with patient reported outcomes regardless of graft source. Loadsols appear to be a suitable tool for use in the clinical rehabilitation setting.

Hop Distance Symmetry Moderately Reflects Knee Biomechanics Symmetry During Landing But Not For Controlled Propulsions.

Landing with poor knee sagittal plane biomechanics has been identified as a risk factor for Anterior Cruciate Ligament (ACL) injury. However, it is unclear if the horizontal hop test battery reflects knee function and biomechanics. To investigate the correlation between clinical limb symmetry index (LSI) and landing and propulsion knee biomechanics during the hop test battery using markerless motion capture. Cross-sectional biomechanics laboratory study. Forty-two participants with and without knee surgery (age 28.0 ± 8.0 years) performed the hop test battery which consisted of a single hop for distance, crossover hop, triple hop, and 6-m timed hop in the order listed. Eight high speed cameras were used to collect simultaneous 3D motion data and Theia 3D (Theia Markerless Inc.) was used to generate 3D body model files. Lower limb joint kinematics were calculated in Visual3D. Correlation (Spearman's ρ) was computed between clinical LSI and symmetry in peak and initial contact (IC) knee flexion angle during propulsion and landing phases of each movement. In the single hop, clinical LSI showed positive correlation with kinematic LSI at peak landing (ρ= 0.39, p=0.011), but no correlation at peak propulsion (ρ= -0.03, p=0.851). In the crossover hop, non-significant correlations were found in both propulsion and landing. In the triple hop, positive correlation was found at peak propulsion (ρ= 0.38, p=0.027), peak landing (ρ= 0.48 - 0.66, p<0.001), and last landing IC (ρ= 0.45, p=0.009). In the timed hop, peak propulsion showed positive correlation (ρ= 0.51, p=0.003). Single hop and triple hop distance symmetry reflected landing biomechanical symmetry better than propulsion symmetry. Poor scores on the hop test battery reflect asymmetrical knee landing biomechanics, emphasizing the importance of continuing to use the hop test battery as part of clinical decision making. 3b.

Lower-extremity inter-joint coordination variability in active individuals with transtibial amputation and healthy males during gait.

This study was aimed to compare the variability of inter-joint coordination in the lower-extremities during gait between active individuals with transtibial amputation (TTAs) and healthy individuals (HIs). Fifteen active male TTAs (age: 40.6±16.24years, height: 1.74±0.09m, and mass: 71.2 ± 8.87kg) and HIs (age: 37.25±13.11years, height: 1.75±0.06m, and mass: 74 ± 8.75kg) without gait disabilities voluntarily participated in the study. Participants walked along a level walkway covered with Vicon motion capture system, and their lower-extremity kinematics data were recorded during gait. The spatiotemporal gait parameters, lower-extremity joint range of motion (ROM), and their coordination and variability were calculated and averaged to report a single value for each parameter based on biomechanical symmetry assumption in the lower limbs of HIs. Additionally, these parameters were separately calculated and reported for the intact limb (IL) and the prosthesis limb (PL) in TTAs individuals. Finally, a comparison was made between the averaged values in HIs and those in the IL and PL of TTAs subjects. The results showed that the IL had a significantly lower stride length than that of the PL and averaged value in HIs, and the IL had a significantly lower knee ROM and greater stance-phase duration than that of HIs. Moreover, TTAs showed different coordination patterns in pelvis-to-hip, hip-to-knee, and hip-to-ankle couplings in some parts of the gait cycle. It concludes that the active TTAs with PLs walked with more flexion of the knee and hip, which may indicate a progressive walking strategy and the differences in coordination patterns suggest active TTA individuals used different neuromuscular control strategies to adapt to their amputation. Researchers can extend this work by investigating variations in these parameters across diverse patient populations, including different amputation etiologies and prosthetic designs. Moreover, Clinicians can use the findings to tailor rehabilitation programs for TTAs, emphasizing joint flexibility and coordination.

Effects of a Total Motion Release (TMR®) Protocol for the Single Leg Squat on Asymmetrical Movement Patterns.

Improving single leg squat (SLS) movement symmetry may benefit rehabilitation protocols. The Total Motion Release® (TMR®) protocol has been theorized to evaluate and improve patient-perceived movement asymmetries. The purpose of this study was to evaluate whether perceived asymmetries identified by a TMR® scoring protocol were related to biomechanical asymmetries and whether improving perceived asymmetries influenced movement mechanics. It was hypothesized that participants with perceived asymmetries would also present with biomechanical asymmetries. A secondary hypothesis was that participants would reduce their perceived asymmetries after performing the TMR® protocol and subsequently have greater biomechanical symmetry. Descriptive Cohort (Laboratory Study). Twenty participants (10 female, 10 male) with self-identified bilateral differences of 10 points or greater on the TMR® scoring scale were recruited for the study. The non-preferred side was defined as the side that scored higher. 3Dimensional motion capture was used to bilaterally assess baseline SLS depth as well as hip, knee, and ankle kinematics and kinetics. For the TMR® protocol, sets of 10 SLSs were performed on the preferred leg until their perceived asymmetries were resolved (i.e., both sides scored equally), or four sets had been completed. Kinematics and kinetics were collected immediately after the intervention and after a 10-minute rest period. Participants had biomechanical asymmetries at baseline for knee flexion, ankle flexion, and knee moments. Following the intervention, participants had reduced TMR® scores on the non-preferred leg, and this coincided with increased knee joint moments on that side. Although perceived asymmetries were resolved after the intervention, kinematic and kinetic asymmetries at the knee and ankle were still present. A TMR® intervention could benefit rehabilitation protocols by reducing factors of dysfunction and increasing the ability of patients to load the non-preferred knee. Further investigations are necessary to elucidate the importance of asymmetrical movement patterns. 3b.

Functional Resistance Training After Anterior Cruciate Ligament Reconstruction Improves Knee Angle and Moment Symmetry During Gait: A Randomized Controlled Clinical Trial

The purpose of this study was to determine 1) whether progressive functional resistance training (FRT) during walking would improve knee biomechanical symmetry after anterior cruciate ligament (ACL) reconstruction and 2) whether the mode of delivery of FRT would have a differential effect on symmetry. Thirty individuals who underwent primary ACL reconstruction at a single institution volunteered for this study. Participants were randomized into one of three groups: 1) BRACE, 2) BAND, or 3) CONTROL. The BRACE group received FRT with a novel robotic knee brace along with real-time kinematic feedback. The BAND group received FRT with a custom resistance band device along with real-time kinematic feedback. The CONTROL group received only real-time kinematic feedback. Participants in all groups received training (2-3/week for 8 weeks) while walking on a treadmill. Knee angle and moment symmetry were calculated immediately prior to beginning the intervention and within 1 week of completing the intervention. Statistical Parametric Mapping was used to assess differences in biomechanical symmetry between groups across time. There was a significant interaction in knee moment symmetry from 21 and 24% of the stance phase (P= .046), in which the BAND group had greater improvements following training compared with both BRACE (P= .043) and CONTROL groups (P= .002). There was also a significant time effect in knee angle symmetry from 68 to 79% of the stance phase (P= .028) and from 97 to 100% of the swing phase (P=.050) in which only the BRACE group showed significant improvements after the intervention (stance: P= .020 and swing: P < .001). The results of this randomized controlled clinical trial indicate that 8 weeks of progressive FRT during treadmill walking in individuals with ACL reconstruction improves knee angle and moment symmetry during gait. The findings suggest that FRT could serve as a potential therapeutic adjuvant to traditional rehabilitation after ACL reconstruction and can help restore knee joint biomechanical symmetry. Level II, randomized controlled trial.

Biomechanical Symmetry During Drop Jump Landing And Takeoff In Adolescent Athletes Following Recent ACL Reconstruction

Biomechanical Symmetry During Drop Jump Landing And Takeoff In Adolescent Athletes Following Recent ACL Reconstruction

Biomechanical Symmetry during Drop Jump Landing and Takeoff in Adolescent Athletes Following Recent Anterior Cruciate Ligament Reconstruction

This study investigated asymmetry between lower extremities during the landing and takeoff phases of a vertical drop jump (VDJ) in adolescent athletes following anterior cruciate ligament reconstruction (ACLR) and examined if performance was affected by reducing jump height. Thirty-three athletes who underwent ACLR and were referred for 3D biomechanical assessment before returning to play (mean age 15.9, SD 1.3 years; 16/33 female; mean time since surgery 7.4, SD 1.2 months) completed the VDJ while kinematics and kinetics were collected using motion capture. Lower extremity symmetry was compared between phases using paired t-tests. Jump height was calculated to measure performance. Asymmetries in ankle inversion, ankle adduction, knee adduction, hip adduction, hip adduction moment, and hip rotation moment were observed in both phases. Asymmetry was also observed in both phases for sagittal moments and power integrals at the knee and ankle and total power integral, with the magnitude of asymmetry being smaller during takeoff for power absorption/generation. Jump height was related to power generation integrals during takeoff but not to the asymmetry of power generation. Since asymmetries are translated from landing through takeoff, rehabilitation should address both phases to decrease injury risk and maximize performance after return to play.

Factors That Predict Sagittal Plane Knee Biomechanical Symmetry After Anterior Cruciate Ligament Reconstruction: A Decision Tree Analysis.

Biomechanical knee asymmetry is commonly present after anterior cruciate ligament (ACL) reconstruction. Factors that could assist in identification of asymmetrical biomechanics after ACL reconstruction could help clinicians in making return-to-play decisions. The purpose of this study is to determine factors that may contribute to knee biomechanical asymmetry present after ACL reconstruction. We hypothesized that quadriceps strength and activation and patient-reported function would allow for identification of patients with symmetrical knee biomechanics. Cross-sectional study. Level 3. Thirty-one subjects (18 women; time since ACL reconstruction = 284.4 ± 53.6 days) who underwent ACL reconstruction and were to return to activity were recruited. Participants completed bilateral assessments of isokinetic quadriceps strength, quadriceps activation using the superimposed burst technique, and biomechanical function testing during a single-leg forward hop. The International Knee Documentation Committee (IKDC) subjective knee form was also completed. Symmetry values were calculated for each variable. Decision trees were utilized to determine which input factors (quadriceps strength symmetry, quadriceps activation symmetry, IKDC score, age, sex, height, mass, graft type) were able to identify participants who had symmetrical knee flexion angles (KFAs) and extension moments. Angles and moments were considered symmetrical if symmetry values were ≥90%. Quadriceps strength and activation symmetry were able to predict whether a patient landed with symmetrical or asymmetrical KFAs, with thresholds of 77.2% strength symmetry and 91.3% activation symmetry being established. Patient-reported function and quadriceps strength were factors that allowed for classification of participants with symmetrical/asymmetrical knee extension moments, with thresholds of 89.1 for the IKDC and 80.0% for quadriceps strength symmetry. Quadriceps strength contributed to both models and appears to be a critical factor for achieving symmetrical knee biomechanics. High patient-reported function and quadriceps activation are also important for restoring knee biomechanical symmetry after ACL reconstruction. Quadriceps strength and activation and patient-reported function may be able to assist clinicians in identifying ACL patients with symmetrical/asymmetrical knee biomechanics.

Limb Stiffness Is Lower In Those Who Rupture Contralateral Non-ACLR Knee Post Primary ACL Surgery

PURPOSE: The aim of this study was to identify biomechanical differences during jump and CoD testing 9 months after ACL reconstruction (ACLR) between those that went on to injure their non-ACLR limb and those that did not at 2 year follow up. METHODS: Nine months after ACLR, 105 males athletes who were returning to pre-injury sport participation (55 going on to suffer contralateral ACL injury/60 matched subjects with no second injury at 2 years post op) were prospectively assessed using isokinetic strength testing and 3D biomechanical analysis of double leg drop jump (DLDJ), single leg drop jump (SLDJ) and planned and unplanned 90° change of direction (CoD) as well as an IKDC questionnaire. Differences in IKDC, strength and jump height measures on the non-ACLR side and in limb symmetry index between groups were analysed with statistical parametric mapping (SPM, 0D unpaired t-test). Biomechanical differences in the jump and CoD tests on the non-ACLR side and in symmetry between groups was analysed with SPM (1d, unpaired t-test). Effect size was calculated using Cohen’s D for all analyses. RESULTS: There was no difference in IKDC score between groups. There was a small effect size difference in quadriceps strength on the non-ACLR side in the group that went on to injure that limb (ES 0.39) with no difference in LSI or across the hamstring strength and jump height tests. There was no difference in measures of biomechanical symmetry between groups for any of the tests and no difference on the non-ACLR side for the CoD tests. There were large effect size differences on the non-ACLR side in the SLDJ and DLDJ for COM stiffness (ES 0.78 & 0.82), ground contact time (ES 0.73 & 0.85), lowering of COM to ankle and knee (ES 0.7 to 0.81), vertical ground reaction force (ES 0.63 to 0.78) representing less stiffness on the non-ACLR side in the group that went on to injure non-ACLR limb after return to sport. CONCLUSION: This study demonstrated clear biomechanical differences on the non-ACLR side in those that went on to injure the ACL in the limb despite little difference in strength and jump measures and measures of symmetry. These results suggest plyometric exercises to improve limb stiffness may be important to reduced injury risk to the non-ACLR limb after primary ACLR.

BIOMECHANICAL SYMMETRY DURING DROP JUMP AND SINGLE-LEG HOP LANDING IN UNINJURED ADOLESCENT ATHLETES

BACKGROUND Symmetry of strength, thigh girth and hop distance is often used as a benchmark in return to sport testing. Using symmetry as a gold standard has been translated into biomechanical testing; however, kinematic and kinetic symmetry during dynamic tasks in adolescents without lower extremity injury is not well understood. The purpose of this study was to assess symmetry in uninjured adolescent athletes during double and single-leg landing tasks. METHODS 36 uninjured athletes (ages 7-15 years, mean 12.4, SD 2.4; 47% female) completed vertical drop jump (DJ) and single-leg hop (SLH) for distance tasks; lower extremity kinematics and kinetics were collected through 3-D motion analysis using a 6 degree-of-freedom model; 2-3 trials per participant per side were analyzed. Differences between dominant and non-dominant limbs from initial contact to peak knee flexion were examined using statistical parametric mapping (SPM), a methodology for performing statistics on time series data. The SPM method allows differences between dominant and non-dominant limbs to be evaluated for statistical significance at all time points throughout the landing movement. RESULTS During both DJ (Figure 1) and SLH (Figure 2), the dominant limb tended to be more internally rotated at the hip throughout landing, but the asymmetry was significant only for short periods early in landing during the DJ (p&lt;0.05) and at mid-landing in the SLH (p=0.01). Additionally, the dominant hip tended to have less abducted positioning throughout both tasks, but differed significantly only shortly after initial contact in the SLH landing (p=0.04). The dominant limb ankle was less inverted (p&lt;0.001) with a lower external inversion moment (p&lt;0.001) during early to mid-landing in the DJ, and less everted (p=0.04) with higher external inversion moment (p=0.05) early in SLH landing. The only asymmetry observed in either task in the sagittal plane was slightly higher external ankle flexion moments (p=0.05) just after initial contact in the DJ. No asymmetries were detected in peak vertical ground reaction force or knee kinematics/kinetics for either task. CONCLUSION/SIGNIFICANCE Uninjured adolescent athletes exhibited only slight asymmetries during double and single-leg landing, primarily at the hip and ankle in the frontal and transverse planes. The hip may perform larger adjustments to accommodate center of mass location, while the ankle fine-tunes the landing as the closest segment to the ground. This study supports that normal biomechanics are symmetric during double and single-leg landing. Biomechanical symmetry is therefore a reasonable target in return to sport assessment. While only small regions of statistically significant asymmetry were identified, it is possible that greater asymmetries are present within individuals. In the grouped analysis, asymmetry towards the dominant side for one individual could offset asymmetry towards the non-dominant side of another individual. In future analysis, we will examine the magnitude and significance of within-subject asymmetry.

Continued Improvements in Quadriceps Strength and Biomechanical Symmetry of the Knee After Postoperative Anterior Cruciate Ligament Reconstruction Rehabilitation: Is It Time to Reconsider the 6-Month Return-to-Activity Criteria?

Patients who undergo anterior cruciate ligament reconstruction (ACLR) present with strength and biomechanical deficits at return to activity (RTA). Deficits in strength and biomechanical symmetry impair function during activity and may predispose patients to subsequent injury. To compare strength and biomechanical function in patients with ACLR at RTA and more than 12 months post-ACLR. Descriptive laboratory study. Research laboratory. A total of 20 participants (12 females, 8 males; age = 21.40 ± 5.60 years, height = 171.3 ± 10.2 cm, mass = 73.21 ± 19.41 kg) who had undergone ACLR and were cleared to RTA were recruited. Strength was measured during knee extension and evaluated by the isometric and isokinetic quadriceps index. Biomechanical function was evaluated using symmetry values for sagittal-plane knee-joint rotations, changes in sagittal-plane knee-joint rotation, knee-extension moments, and changes in knee-extension moment that were recorded during a single-legged forward hop. Self-reported function was measured using the International Knee Documentation Committee Subjective Knee Evaluation Form. Participants were assessed at RTA (212.25 ± 28.11 days) and more than 12 months post-ACLR (556.25 ± 230.89 days). At RTA, strength and biomechanical values were less than 80% symmetric. We observed improvements from RTA to more than 12 months post-ACLR for the isometric quadriceps index ( F1,18 = 29.22, P < .001), isokinetic quadriceps index ( F1,18 = 10.88, P = .004), sagittal-plane knee-joint rotations ( F1,19 = 9.58, P = .006), change in sagittal-plane knee-joint rotations ( F1,19 = 7.83, P = .01), knee-extension moments ( F1,19 = 5.73, P = .03), change in knee-extension moments ( F1,19 = 21.10, P < .001), and self-perceived function ( F1,19 = 11.50, P = .003). Of the 7 variables that showed improvement at more than 12 months post-ACLR, only 3 met the recommended criteria (≥90%). Patients with ACLR showed asymmetry in strength and biomechanics at RTA. These asymmetries, along with self-perceived function, improved over time. However, despite improvements in strength and biomechanics at RTA, asymmetries of more than 10% were still present more than 12 months post-ACLR.

Biomechanical symmetry in elite rugby union players during dynamic tasks: an investigation using discrete and continuous data analysis techniques

BackgroundWhile measures of asymmetry may provide a means of identifying individuals predisposed to injury, normative asymmetry values for challenging sport specific movements in elite athletes are currently lacking in the literature. In addition, previous studies have typically investigated symmetry using discrete point analyses alone. This study examined biomechanical symmetry in elite rugby union players using both discrete point and continuous data analysis techniques.MethodsTwenty elite injury free international rugby union players (mean ± SD: age 20.4 ± 1.0 years; height 1.86 ± 0.08 m; mass 98.4 ± 9.9 kg) underwent biomechanical assessment. A single leg drop landing, a single leg hurdle hop, and a running cut were analysed. Peak joint angles and moments were examined in the discrete point analysis while analysis of characterising phases (ACP) techniques were used to examine the continuous data. Dominant side was compared to non-dominant side using dependent t-tests for normally distributed data or Wilcoxon signed-rank test for non-normally distributed data. The significance level was set at α = 0.05.ResultsThe majority of variables were found to be symmetrical with a total of 57/60 variables displaying symmetry in the discrete point analysis and 55/60 in the ACP. The five variables that were found to be asymmetrical were hip abductor moment in the drop landing (p = 0.02), pelvis lift/drop in the drop landing (p = 0.04) and hurdle hop (p = 0.02), ankle internal rotation moment in the cut (p = 0.04) and ankle dorsiflexion angle also in the cut (p = 0.01). The ACP identified two additional asymmetries not identified in the discrete point analysis.ConclusionsElite injury free rugby union players tended to exhibit bi-lateral symmetry across a range of biomechanical variables in a drop landing, hurdle hop and cut. This study provides useful normative values for inter-limb symmetry in these movement tests. When examining symmetry it is recommended to incorporate continuous data analysis techniques rather than a discrete point analysis alone; a discrete point analysis was unable to detect two of the five asymmetries identified.Electronic supplementary materialThe online version of this article (doi:10.1186/s13102-015-0006-9) contains supplementary material, which is available to authorized users.

Quadriceps Strength Asymmetry After Anterior Cruciate Ligament Reconstruction Alters Knee Joint Biomechanics and Functional Performance at Time of Return to Activity

Background: Quadriceps strength deficits are observed clinically after anterior cruciate ligament (ACL) injury and reconstruction and are often not overcome despite rehabilitation. Given that quadriceps strength may be important for achieving symmetrical joint biomechanics and promoting long-term joint health, determining the magnitude of strength deficits that lead to altered mechanics is critical. Purpose: To determine if the magnitude of quadriceps strength asymmetry alters knee and hip biomechanical symmetry as well as functional performance and self-reported function. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A total of 73 patients were tested at the time they were cleared for return to activity after ACL reconstruction. Quadriceps strength and activation, scores on the International Knee Documentation Committee form, the hop for distance test, and sagittal plane lower extremity biomechanics were recorded while patients completed a single-legged hop. Results: Patients with high and moderate quadriceps strength symmetry had larger central activation ratios as well as greater limb symmetry indices on the hop for distance compared with patients with low quadriceps strength symmetry (P < .05). Similarly, knee flexion angle and external moment symmetry were higher in the patients with high and moderate quadriceps symmetry compared with those with low symmetry (P < .05). Quadriceps strength was found to be associated with sagittal plane knee angle and moment symmetry (P < .05). Conclusion: Patients with low quadriceps strength displayed greater movement asymmetries at the knee in the sagittal plane. Quadriceps strength was related to movement asymmetries and functional performance. Rehabilitation after ACL reconstruction needs to focus on maximizing quadriceps strength, which likely will lead to more symmetrical knee biomechanics.

Improvements in biomechanical symmetry are related to improved functional performance following total knee arthroplasty

Improvements in biomechanical symmetry are related to improved functional performance following total knee arthroplasty