Knee Offloading by Patients During Walking and Running After Meniscectomy.

Background: Changes in knee loading have been reported after meniscectomy. Knee loading has previously been assessed during jogging and treadmill running rather than overground running, which could give altered results. Purpose/Hypothesis: The purpose of this study was to evaluate knee function during overground running and walking after meniscectomy. It was hypothesized that the affected limb would demonstrate higher external knee adduction moment, lower knee flexion moment (KFM), and lower knee rotation moment (KRM) compared with the contralateral limb and with healthy individuals. Study Design: Controlled laboratory study. Methods: Kinematic and kinetic data were collected during running and walking in individuals after a meniscectomy and healthy individuals. Total knee joint moments (TKJM) were calculated from the sagittal, frontal, and transverse knee moments. Isometric quadriceps strength, perceived knee function, and kinesiophobia were also assessed. A mixed linear model compared differences between the affected leg, the contralateral leg, and the healthy leg. Results: Data were collected on 20 healthy individuals and 30 individuals after a meniscectomy (mean ± SD, 5.7 ± 2.9 months postsurgery), with 12, 16, and 2 individuals who had medial, lateral, and both medial and lateral meniscectomy, respectively. The affected limb demonstrated lower TKJM (P < .001), KFM (P = .004), and KRM (P < .001) during late stance of walking compared with the healthy group. Lower TKJM and KFM were observed during running in the affected limb compared with the contralateral limb and healthy group. No significant differences were observed between contralateral and healthy limbs except for KRM during late stance of walking. Lower quadriceps strength was observed in the affected (P < .001) and contralateral limbs (P = .001) compared with the healthy group. Individuals after a meniscectomy also reported greater kinesiophobia (P = .006) and lower perceived knee function (31.1%; P < .001) compared with the healthy group. Conclusion: After meniscectomy, individuals who sustained a traumatic meniscal injury showed lower TKJM in the affected limb compared with the contralateral limb and healthy individuals. This decrease in TKJM can be attributed to altered knee-loading strategies in the sagittal and transverse planes. Clinical Relevance: Improving movement strategies, quadriceps strength, and kinesiophobia through rehabilitation approaches will allow individuals to load their knee appropriately when returning to sport. Registration: NCT03379415 (ClinicalTrials.gov identifier).

No differences in knee joint loading between individuals who had a medial or lateral meniscectomy: An ancillary study.

BACKGROUND: Arthroscopic partial meniscectomy is a frequently undertaken procedure for traumatic meniscal injuries. The location of knee joint degeneration and long-term prognosis differs between knees who have had a medial or lateral meniscectomy. However, there is no evidence comparing knee loading following a medial or lateral meniscectomy during sporting tasks. This study compared knee loading during walking and running between individuals who either had a medial or lateral meniscectomy. METHODS: Knee kinematic and kinetic data were collected during walking and running in individuals three to twelve months post-surgery. Participants were grouped according to the location of surgery (medial, n = 12, and lateral, n = 16). An independent t-test compared knee biomechanics between the groups and Hedge's g effects sizes were also conducted. RESULTS: External knee adduction and knee flexion moments were similar between groups for walking and running with negligible to small effect sizes (effect size, 0.08-0.30). Kinematic (effect size, 0.03-0.22) and spatiotemporal (effect size, 0.02-0.59) outcomes were also similar between the groups. CONCLUSIONS: The lack of differences in surrogate knee loading variables between medial and lateral meniscectomy groups was unexpected. These findings suggest that combining groups in the short-term period following surgery is applicable. However, the data presented in this study cannot explain the differences in long-term prognosis between medial and lateral meniscectomies.

Use of an isometric mid-thigh pull test during musculoskeletal rehabilitation: can the criterion values from the updated British Army physical employment standards be used to inform UK Defence Rehabilitation practice?

INTRODUCTION: Objective outcome measures that can quantify the force generating capacity of the lower limb are required to allow clinicians to accurately measure functional status and treatment adaptations over time. The aim of this prospective observational cohort study is to: (1) evaluate the acceptability of the isometric mid-thigh pull (IMTP) test as a measure of functional strength with military personnel undergoing residential hip pain rehabilitation; (2) compare the peak force values recorded against the updated Army physical employment standards (PES) assessment criteria and (3) assess if the minimum PES required of military personnel has the potential to inform clinical decision making and return to duty criteria within UK Defence Rehabilitation. METHODS: Acceptability was assessed against patient's adherence to the testing procedures and test burden. Clinician acceptability was assessed against ease of administration and safety of test procedure. Hip pain was recorded before, immediately following and 1 hour after testing. Net peak force was recorded using portable force plates. RESULTS: Full patient and clinician acceptability to IMTP testing procedures were demonstrated. Minimal changes in visual analogue scale (VAS) pain scores were demonstrated between baseline values at rest and follow-up. Despite being medically downgraded and functionally compromised due to chronic hip pain, 100% of patients met the PES expected on entry to the British Army and 79% met the PES expected at the end of basic training. CONCLUSION: The IMTP provides rehabilitation clinicians with an objective quantifiable measure of maximum muscle strength that can be used early in the rehabilitation care pathway. Based on our finding, it is unclear if the current British Army PES can be used as a criterion standard in Defence Rehabilitation. Therefore, further research focused on generating clinically relevant patient-specific IMTP score criteria, with a larger sample of diverse diagnostic sub-groups is required.

Evaluation of a multi-sensor Leap Motion setup for biomechanical motion capture of the hand.

The Leap Motion controller (LMC) offers a low-cost means of markerless hand tracking, however, its utility is limited by a small field of view and reliance on appropriate sensor positioning. A recent update from Leap Motion has enabled the use of a multiple LMC device on a single computer, allowing the tracking of hands from multiple orientations, potentially overcoming the aforementioned limitations. This study describes a method of implementing a multi-LMC setup and evaluates its effect on the validity and reliability of the derived kinematics. This study implemented a Kabsch algorithm and Kalman filter to re-orientate and fuse the trajectories captured by three LMC at different orientations. Reliability was assessed by comparing between-day differences in maximum joint angles (ΔMJA) and a calculated coefficient of multiple correlations (CMC). Validity was assessed by comparing the LMC to the gold standard, a Vicon markered motion capture (MMC) system, and calculating the ΔMJA and applying the linear fit method. The proposed method was evaluated by comparing the reliability and validity of the single-LMC setups to the multi-LMC setup. A multi-LMC setup proved successful in improving the reliability and validity of kinematic data, most notably where reliability and validity were poor and variation was high between the single-LMC setups. Findings suggest that through implementing the proposed method, limitations associated with single-LMC setups, notably its reliance on optimal sensor positioning, can be overcome.

Biomechanical differences between military patients with patellar tendinopathy and asymptomatic controls during single-leg squatting and gait - A statistical parametric mapping study.

BACKGROUND: Prior identification of biomechanical differences between patients with patellar tendinopathy and healthy controls has utilised time-discrete analysis which is susceptible to type I error when multiple comparisons are uncorrected. We employ statistical parametric mapping to minimise the risk of such error, enabling more appropriate clinical decision-making. METHODS: Lower-limb biomechanics of 21 patients with patellar tendinopathy and 22 controls were captured during walking and three types of squats. A statistical parametric mapping two-sample t-test was used to identify kinematic and kinetic differences between groups for each joint. Paired t-tests were used to compare pain before and after tasks, in patients with patellar tendinopathy. FINDINGS: During walking, cases demonstrated reduced knee joint power during initial contact and hip joint power during terminal stance. In squatting, cases demonstrated increased knee abduction angles at various time points of the small knee bend and single-leg squat. Cases demonstrated reduced knee internal rotation moment during the deepest portion of the single-leg squat and single-leg decline squat. INTERPRETATION: Gait appears unaffected by patellar tendinopathy, likely due to low task difficulty. Elevated knee abductions angles during squatting were confirmed as a key difference in patients with patellar tendinopathy. Reduced knee internal rotation moments in patients were attributed to a potential reduction in hip external rotator strength and possible pain avoidance strategy; however further evidence is required to substantiate these claims. Findings provide a clear rationale for rehabilitation programs to focus on knee stabilisation and strengthening of the muscles surrounding the hip.