CONTEXT Little is known about the effects of static alignment on neuromuscular control of the knee during dynamic motion. OBJECTIVE To evaluate the isolated and combined effects of quadriceps angle (QA) and navicular drop (ND) on neuromuscular responses to a weight-bearing perturbation. DESIGN Mixed-model, repeated-measures design. SETTING Sports medicine and athletic training research la...

In the surgery of cerebral palsy, tenotomy of the hamstrings near their insertion, with or without reinsertion into the femur, is an established and useful operation (Eggers 1952, Pollock and Sharrard 1958). Division of the tendinous origin of the hamstring muscles is not so well known. We have done this operation with considerable success when the quadriceps muscle is acting strongly and tight...

PURPOSE Children with cerebral palsy (CP) often use a crouch gait pattern that has disturbances in the knee joint kinematics. Although the length and rate of lengthening of the hamstring musculature have been speculated to be the reason that these disturbances are not adequately dissipated, this relationship has not been adequately explored. The purpose of this exploratory investigation was to ...

BACKGROUND AND PURPOSE Despite the belief that after cerebral infarction only limited functional gains are possible beyond the subacute period, we tested the hypothesis that a 12-week program of "task-oriented" treadmill exercise would increase muscle strength and decrease spastic reflexes in chronic hemiparetic patients. METHODS Fourteen subjects, aged 66+/-3 (mean+/-SEM) years, with residua...

Harness supported treadmill ambulation has been recommended for patients as a way of decreasing loads on the healing tissues, conserving energy and reducing pain. We quantified muscle activation levels around the knee and metabolic responses during harness supported treadmill walking. Ten healthy recreational athletes (age 28.9+/-7.8 years) walked on the treadmill (1.34 m/s) for 5 min each at f...

Our purpose was to determine if females demonstrate decreased hamstrings to quadriceps peak torque (H/Q) ratios compared to males and if H/Q ratios increase with increased isokinetic velocity in both sexes. Maturation disproportionately increases hamstrings peak torque at high velocity in males, but not females. Therefore, we hypothesised that mature females would demonstrate decreased H/Q rati...

INTRODUCTION Hamstring strain injuries are common in sports that involve high-speed running. It remains uncertain whether the hamstrings are susceptible to injury during late swing phase, when the hamstrings are active and lengthening, or during stance, when contact loads are present. In this study, we used forward dynamic simulations to compare hamstring musculotendon stretch, loading, and wor...

PURPOSE The purpose of this study was to investigate the effects of a progressive 10-wk aquatic resistance training on neuromuscular performance and muscle mass of the knee extensors and flexors in healthy women. METHODS Twenty-four healthy women (34.2 +/- 3.9 yr) were randomly assigned into aquatic exercise (N = 12) and control group (N = 12). Maximum knee extension and flexion torques were ...

OBJECTIVE To determine the association of quadriceps and hamstrings strength to anterior cruciate ligament (ACL) injury risk in female athletes. The primary hypothesis was that there would be decreased knee flexor and increased knee extensor strength in female athletes who went on to ACL injured status (FACL) compared to uninjured female (FC) and male (MC) control subjects. STUDY DESIGN Match...

The objective of this study was to examine the response and recovery to a single set of maximal, low and high angular velocity isokinetic leg extension-flexion contractions with boys. Sixteen boys (11-14 yrs) performed 10 isokinetic contractions at 60°.s-1 (Isok60) and 300°.s-1 (Isok300). Three contractions at both velocities, blood lactate and ratings of perceived exertion were monitored prete...