To evaluate the current evidence concerning kinematic and kinetic strategies adopted during dynamic landing tasks by patients with anterior cruciate ligament reconstruction (ACLR).
PubMed, Web of ...Science.
Original research articles that evaluated kinematics or kinetics (or both) during a landing task in those with a history of ACLR were included.
Methodologic quality was assessed using the modified Downs and Black checklist. Means and standard deviations for knee or hip (or both) kinematics and kinetics were used to calculate Cohen d effect sizes and corresponding 95% confidence intervals between the injured limb of ACLR participants and contralateral or healthy matched limbs. Data were further stratified by landing tasks, either double- or single-limb landing. A random-effects-model meta-analysis was used to calculate pooled effect sizes and 95% confidence intervals.
The involved limbs of ACLR patients demonstrated clinically and significantly lower knee-extension moments during double-legged landing compared with healthy contralateral limbs and healthy control limbs (Cohen d range = -0.81 to -1.23) and decreased vertical ground reaction forces when compared with healthy controls, regardless of task (Cohen d range = -0.39 to -1.75).
During single- and double-legged landing tasks, individuals with ACLR demonstrated meaningful reductions in injured-limb knee-extension moments and vertical ground reaction forces. These findings indicate potential unloading of the injured limb after ACLR, which may have significant implications for secondary ACL injury and long-term joint health.
Anterior cruciate ligament (ACL) injury and ACL reconstruction (ACLR) result in persistent alterations in lower extremity movement patterns. The progression of lower extremity biomechanics from the ...time of injury has not been described.
To compare the 3-dimensional (3D) lower extremity kinematics and kinetics of walking among individuals with ACL deficiency (ACLD), individuals with ACLR, and healthy control participants from 3 to 64 months after ACLR.
We searched PubMed and Web of Science from 1970 through 2013.
We selected only articles that provided peak kinematic and kinetic values during walking in individuals with ACLD or ACLR and comparison with a healthy control group or the contralateral uninjured limb.
A total of 27 of 511 identified studies were included. Weighted means, pooled standard deviations, and 95% confidence intervals were calculated for the healthy control, ACLD, and ACLR groups at each reported time since surgery. The magnitude of between-groups (ACLR versus ACLD, control, or contralateral limb) differences at each time point was evaluated using Cohen d effect sizes and associated 95% confidence intervals. Peak knee-flexion angle (Cohen d = -0.41) and external knee-extensor moment (Cohen d = -0.68) were smaller in the ACLD than in the healthy control group. Peak knee-flexion angle (Cohen d range = -0.78 to -1.23) and external knee-extensor moment (Cohen d range = -1.39 to -2.16) were smaller in the ACLR group from 10 to 40 months after ACLR. Reductions in external knee-adduction moment (Cohen d range = -0.50 to -1.23) were present from 9 to 42 months after ACLR.
Reductions in peak knee-flexion angle, external knee-flexion moment, and external knee-adduction moment were present in the ACLD and ACLR groups. This movement profile during the loading phase of gait has been linked to knee-cartilage degeneration and may contribute to the development of osteoarthritis after ACLR.
Anterior cruciate ligament (ACL) injury and ACL reconstruction (ACLR) result in persistent alterations in lower extremity movement patterns. The progression of lower extremity biomechanics from the ...time of injury has not been described.
To compare the 3-dimensional (3D) lower extremity kinematics and kinetics of walking among individuals with ACL deficiency (ACLD), individuals with ACLR, and healthy control participants from 3 to 64 months after ACLR.
We searched PubMed and Web of Science from 1970 through 2013.
We selected only articles that provided peak kinematic and kinetic values during walking in individuals with ACLD or ACLR and comparison with a healthy control group or the contralateral uninjured limb.
A total of 27 of 511 identified studies were included. Weighted means, pooled standard deviations, and 95% confidence intervals were calculated for the healthy control, ACLD, and ACLR groups at each reported time since surgery. The magnitude of between-groups (ACLR versus ACLD, control, or contralateral limb) differences at each time point was evaluated using Cohen d effect sizes and associated 95% confidence intervals. Peak knee-flexion angle (Cohen d = -0.41) and external knee-extensor moment (Cohen d = -0.68) were smaller in the ACLD than in the healthy control group. Peak knee-flexion angle (Cohen d range = -0.78 to -1.23) and external knee-extensor moment (Cohen d range = -1.39 to -2.16) were smaller in the ACLR group from 10 to 40 months after ACLR. Reductions in external knee-adduction moment (Cohen d range = -0.50 to -1.23) were present from 9 to 42 months after ACLR.
Reductions in peak knee-flexion angle, external knee-flexion moment, and external knee-adduction moment were present in the ACLD and ACLR groups. This movement profile during the loading phase of gait has been linked to knee-cartilage degeneration and may contribute to the development of osteoarthritis after ACLR.
To compare the effects of power training (PWT) and a high-speed yoga program on physical performances in older patients with Parkinson disease (PD), and to test the hypothesis that both training ...interventions would attenuate PD symptoms and improve physical performance.
Randomized controlled trial.
A laboratory of neuromuscular research and active aging.
Patients with PD (N=41; mean age ± SD, 72.2 ± 6.5y).
Two high-speed exercise interventions (specifically designed yoga program and PWT) were given for 12 weeks (twice a week), and 1 nonexercise control group.
Unified Parkinson Disease Rating Scale motor score (UPDRSMS), Berg Balance Scale (BBS), Mini-Balance Evaluation Systems Test (Mini-BESTest), Timed Up and Go, functional reach, single leg stance (SLS), postural sway test, 10-m usual and maximal walking speed tests, 1 repetition maximum (RM), and peak power (PPW) for leg press.
For the posttests, both training groups showed significant improvements (P<.05) in all physical measurements except functional reach on the more affected side, SLS, and postural sway compared with the pretests, and significantly better scores for UPDRSMS, BBS, Mini-BESTest, Timed Up and Go, functional reach on the less affected side, 10-m usual and maximal walking speed tests, 1RM, and PPW than controls, with no differences detected between the yoga program and PWT.
Both the specially designed yoga program and PWT programs can significantly improve physical performance in older persons with PD.
Previously, the most common treatment for a concussion was prolonged physical and cognitive rest. Recently, researchers have suggested that earlier physical activity (PA) may be better at promoting ...recovery. Researchers have not evaluated the relationship between free-living PA (eg, walking) and symptom reporting or recovery duration.
To assess the relationship between free-living PA participation and 2 recovery outcomes in college-aged adults with a concussion.
Prospective cohort.
National Collegiate Athletic Association Division I and III universities.
Thirty-two college-aged adults (68.8% female, age = 19.8 ± 1.4 years) with a concussion.
Participants completed a postconcussion symptom evaluation at visits 1 (<72 hours from concussion) and 2 (8 days later). Between visits, each participant's PA was monitored using an Actigraph GT9X Link PA monitor and expressed as total PA (counts per minute) and percentage of PA time spent in moderate-to-vigorous intensity (%MVPA). Recovery time was the number of days from injury occurrence to medical clearance. With separate hierarchical multiple regressions, we evaluated the relationship between total PA and each recovery variable (visit 2 symptom severity, recovery time). Additionally, with separate exploratory hierarchical multiple regressions, we evaluated the relationship between %MVPA and each recovery variable. Statistical significance was set a priori at P ≤ .05.
Participants averaged 2446 ± 441 counts per minute and spent 12.1% ± 4.2% of their PA performing MVPA. Participants yielded median (interquartile) symptom severities of 28 (24) and 2 (8) for visit 1 and 2, respectively. Average recovery time was 14.7 ± 7.5 days. Total PA did not significantly contribute to the model for visit 2 symptom severity (P = .122) or recovery time (P = .301). Similarly, %MVPA had little contribution to the model for visit 2 symptom severity (P = .358) or recovery time (P = .276).
We suggest that free-living PA may not be enough to reduce symptoms or shorten recovery. Thus, clinicians may need to provide patients with more structured PA protocols mimicking findings from previous researchers.
Context:
Quadriceps function is a significant contributor to knee joint health that is influenced by central and peripheral factors, especially after anterior cruciate ligament reconstruction (ACLR).
...Objective:
To assess differences of unilateral quadriceps isometric strength and activation between the involved limb and contralateral limb of individuals with ACLR and healthy controls.
Data Sources:
Web of Science, SportDISCUS, PubMed, CINAHL, and the Cochrane Database were all used during the search.
Study Selection:
A total of 2024 studies were reviewed. Twenty-eight studies including individuals with a unilateral history of ACLR, isometric knee extension strength normalized to body mass, and quadriceps activation measured by central activation ratios (CARs) through a superimposed burst technique were identified for meta-analysis. The methodological quality of relevant articles was assessed using a modified Downs and Black scale. Results of methodological quality assessment ranged from low to high quality (low, n = 10; moderate, n = 8; high, n = 10).
Study Design:
Meta-analysis.
Level of Evidence:
Level 2.
Data Extraction:
Means, standard deviations, and sample sizes were extracted from articles, and magnitude of between-limb and between-group differences were evaluated using a random-effects model meta-analysis approach to calculate combined pooled effect sizes (ESs) and 95% CIs. ESs were classified as weak (d < 0.19), small (d = 0.20-0.49), moderate (d = 0.50-0.79), or large (d > 0.80).
Results:
The involved limb of individuals with ACLR displayed lower knee extension strength compared with the contralateral limb (ES, –0.78; lower bound LB, –0.99; upper bound UB, –0.58) and healthy controls (ES, –0.76; LB, –0.98; UB, –0.53). The involved limb displayed a lower CAR compared with healthy controls (ES, –0.84; LB, –1.18; UB, –0.50) but not compared with the contralateral limb (ES, –0.15; LB, –0.37; UB, 0.07). The ACLR contralateral limb displayed a lower CAR (ES, –0.73; LB, –1.39; UB, –0.07) compared with healthy control limbs but similar knee extension strength (ES, –0.24; LB, –0.68; UB, –0.19).
Conclusion:
Individuals with ACLR have bilateral CAR deficits and involved limb strength deficits that persist years after surgery. Deficits in quadriceps function may have meaningful implications for patient-reported and objective outcomes, risk of reinjury, and long-term joint health after ACLR.
Birchmeier, T, Lisee, C, Geers, B, and Kuenze, C. Reactive strength index and knee extension strength characteristics are predictive of single-leg hop performance after anterior cruciate ligament ...reconstruction. J Strength Cond Res 33(5): 1201-1207, 2019-Single-leg hop distance is incorporated into return to sport criteria after anterior cruciate ligament reconstruction (ACLR) because of its relationship with knee extension strength; however, it may be related to other strength and plyometric characteristics. The purpose of this study was to assess the association between isometric knee extension strength and plyometric characteristics, including amortization and reactive strength index (RSI), measured during a single-leg drop vertical jump and single-leg hop performance in individuals with unilateral ACLR. Participants attended 2 testing sessions. During the first session, a biomechanical analysis using a 3D motion capture system was performed to measure RSI and amortization during a single-leg drop vertical jump for maximal height. Participants completed a single hop and a triple hop for maximal distance. During the second session, isometric knee extension strength was measured during a maximal voluntary isometric contraction. Strength characteristics included peak torque, rate of torque development (RTD), RTD 0-100 ms (RTD 100), and RTD 100-200 ms (RTD 200). Fifty-two individuals (17 men/35 women) participated. Multivariable regression models revealed jump height, peak torque, and RTD 200 explained 60.9% of the variance in normalized single-leg hop distance (p < 0.001). Reactive strength index, peak torque, RTD 200, and RTD 100 significantly explained 61.8% of the variance in normalized triple hop distance (p < 0.001). Single hop distance may indicate improved knee extension strength, whereas triple hop distance may indicate improvement in reactive strength. Training to improve RSI may improve triple hop performance and clinical outcomes in this population.
Assessments using dynamic postural control tests, like the Star Excursion Balance Test (SEBT), in combination with three-dimensional (3D) motion analysis can yield critical information regarding a ...subject’s lower limb movement patterns. 3D analysis can provide a clear understanding of the mechanisms that lead to specific outcome measures on the SEBT. Currently, the only technology for 3D motion analysis during such tests is expensive marker-based motion analysis systems, which are impractical for use in clinical settings. In this study we validated the use of the Microsoft Kinect as a cost-effective and marker-less alternative to more complex and expensive gold-standard motion analysis systems. Ten healthy subjects performed the SEBT while their lower limb kinematics were measured concurrently using a traditional motion capture system and a single Kinect v2 sensor. Analyses revealed errors in lower limb kinematics of less than 5°, except for the knee frontal-plane angle (5.7°) in the posterior-lateral direction. Ensemble curve analyses supported these findings, showing minimal between-system differences in all directions. Additionally, we found that the Kinect displayed excellent agreement (ICC3,k=0.99) and consistency (ICC2,k=0.99) when assessing reach distances in all directions. These results indicate that this low-cost and easy to implement technology may provide to clinicians a simple tool to simultaneously assess reach distances while developing a clearer understanding of the lower extremity movement patterns associated with SEBT performance in healthy and injured populations.
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