Multi-plane, multi-joint lower extremity support moments during a rapid deceleration task: Implications for knee loading.

The principle of lower limb support, and the contribution of hip, knee and ankle moments to an overall limb support strategy for an impact-like, rapid deceleration movement may help explain individual moment magnitude changes, thereby providing insight into how injury might occur or be avoided. Twenty subjects performed single limb, impact-like, deceleration landings at three different knee flexion angles in the range of 0-25, 25-50 and 50-75°. Kinematic and kinetic measures identified hip, knee and ankle moment contribution to limb support moments (LSMs) in three planes.

The effect of augmented somatosensory feedback on standing postural sway.

Impaired balance resulting from reduced postural control occurs with aging and various medical conditions. Sensory input for balance control is provided by the visual, vestibular and somatosensory systems. Previous research suggests that increased proprioceptive feedback from various lower extremity devices improves balance.

The effect of firefighter protective garments, self-contained breathing apparatus and exertion in the heat on postural sway.

Fire suppression wearing thermal protective clothing (TPC) and self-contained breathing apparatus (SCBA) challenges a firefighter's balance and may explain firefighter falls. Postural control based on force plate centre of pressure (COP) was compared for healthy subjects wearing TPC and SCBA before and after 20 min of heavy physical exertion in hot conditions. Baseline measures with and without TPC and SCBA (two different SCBA cylinder masses) were compared before and after exertion that included elements of fire suppression activities in an environmental chamber.

Posterior glenohumeral thermal capsulorraphy, capsular imbrication and labral repair with complication of adhesive capsulitis: a modified rehabilitation approach.

Background: Isolated atraumatic posterior glenohumeral instability is rare. Use of thermal capsulorraphy for glenohumeral instability is considered controversial. This case study describes a modified rehabilitation protocol for a patient who underwent a multistep arthroscopic procedure for isolated posterior glenohumeral instability with a postoperative complication of adhesive capsulitis.

Effect of knee flexion angle on ground reaction forces, knee moments and muscle co-contraction during an impact-like deceleration landing: implications for the non-contact mechanism of ACL injury.

Investigating landing kinetics and neuromuscular control strategies during rapid deceleration movements is a prerequisite to understanding the non-contact mechanism of ACL injury. The purpose of this study was to quantify the effect of knee flexion angle on ground reaction forces, net knee joint moments, muscle co-contraction and lower extremity muscles during an impact-like, deceleration task. Ground reaction forces and knee joint moments were determined from video and force plate records of 10 healthy male subjects performing rapid deceleration single leg landings from a 10.

Skeletal muscle fiber types in the ghost crab, Ocypode quadrata: implications for running performance.

Ghost crabs possess rapid running capabilities, which make them good candidates for comparing invertebrate exercise physiology with that of more extensively studied vertebrates. While a number of studies have examined various aspects of running physiology and biomechanics in terrestrial crabs, none to date have defined the basic skeletal muscle fiber types that power locomotion. In the current study, we investigated skeletal muscle fiber types comprising the extensor and flexor carpopodite muscles in relation to running performance in the ghost crab.

Altering asymmetric limb loading after hip arthroplasty using real-time dynamic feedback when walking.

Objective: To evaluate a walking program incorporating real-time biofeedback to reduce asymmetric limb loading after total hip arthroplasty (THA).

Design: Within-subject clinical intervention.

Setting: Biomechanics laboratory.

Differences in peak knee valgus angles between individuals with high and low Q-angles during a single limb squat.

Background: Differences in anatomical alignment between genders have been suggested as causes of the disparity in anterior cruciate ligament injury rates. A larger Q-angle may be associated with increased knee valgus during movement resulting in anterior cruciate ligament strain. This study investigated whether healthy college-aged subjects with a large Q-angle display greater peak knee valgus during a single limb squat compared to those with a small Q-angle.

Kinetic changes with fatigue and relationship to injury in female runners.

Purpose: This research examined how ground reaction forces (GRF) changed with fatigue induced by an exhaustive treadmill run in female runners. A separate retrospective and prospective analysis correlated initial magnitude of GRF and fatigue-induced changes in GRF with lower-extremity injury.

Methods: Ninety adult female runners had vertical GRF measured before and after an exhaustive treadmill run.

Asymmetric limb loading with true or simulated leg-length differences.

Unequal leg lengths result in asymmetric limb loading but opinions vary on the size of the difference inducing abnormal loading, and which limb sustains the greater load. Our study compared limb-loading asymmetries during walking for subjects with anatomic leg-length discrepancies between 1.0 and 3 cm, subjects without length discrepancies, and for subjects with a simulated a 1.