Computer models of the musculoskeletal system frequently represent the force-length behavior of muscle with a lumped-parameter model. Lumped-parameter models use simple geometric shapes to characterize the arrangement of muscle fibers and tendon; this may inaccurately represent changes in fiber length and the resulting force-length behavior, especially for muscles with complex architecture. The...

Arthroscopy is a surgical technique useful in the treatment of intra- and extra-articular hip pathologies, including femoroacetabular impingement (FAI). In the arthroscopic treatment of pincer-type FAI, tendon interposition of the reflected head of the rectus femoris frequently hinders acetabular edge resection in the anterior-superior region (acetabuloplasty) and labrum repositioning, even cau...

The currently most plausible pathophysiologic theory for the etiology of pain in patients with patellofemoral pain syndrome involves abnormal mechanical stress to the patellofemoral joint. At this time, there is no consensus nor is there a sufficient body of research evidence to guide management of patients with patellofemoral pain syndrome. This means that clinicians have to rely to some exten...

BACKGROUND Rectus femoris injuries are common among athletes, especially in kicking sports such as soccer; however, proximal rectus femoris avulsions in athletes are a relatively rare entity. PURPOSE/HYPOTHESIS The purpose of this study was to describe and report the results of an original technique of surgical excision of the proximal tendon remnant followed by a muscular suture repair. Our ...

[Purpose] The purpose of this study was to show the effect of different forefoot and heel support surfaces on the activities of the rectus femoris and medial hamstring muscles during the sit-to-stand task while wearing high-heel shoes. [Subjects] Fifteen female subjects were recruited. [Methods] The muscle activities of the rectus femoris and hamstring muscles were recorded using an MP150 syste...

This study investigated the time course of changes of bone and muscle atrophy in mice with immobilization by denervation and fixation. The animals were fifty-two male C57 BL/6J mice, aged 10 weeks old. Eight mice were used as the base line, and the remaining ones were cut at the sciatic nerve of the left hind limb and fixed with a plaster cast. At week 1, 2, 3, and 4 after the operation, a cros...

[Purpose] The purpose of the study was to design and implement a multichannel dynamic functional electrical stimulation system and investigate acute effects of functional electrical stimulation of the tibialis anterior and rectus femoris on ankle and knee sagittal-plane kinematics and related muscle forces of hemiplegic gait. [Subjects and Methods] A multichannel dynamic electrical stimulation ...

The aim of this investigation was to study the effect of non-involved-side exercise on the involved (paretic) leg-muscle of patients with stroke. Each of the ten adults studied attempted to perform, while seated, a predetermined sequence of the following actions : (1) a voluntary knee extension on the involved side; (2) a maximal, isometric knee-flexion on the non-involved side; (3) a maximal, ...

A study was conducted to evaluate nutritional value for twenty-one pork muscles. Ten market-weight crossbred pigs (five gilts and five barrows) were used for evaluating proximate chemical composition, cholesterol, total iron, calorie and fatty acid contents. As preliminary analysis revealed no noticeable sex effect, pooled data from both sexes were used for the final analysis. M. rectus femoris...

This study was designed to measure in vivo muscle architecture of the rectus femoris in adults with Down syndrome, testing possible relationships with functional parameters of the knee motion. Ten adults with Down syndrome and ten typically developed participated in the study. Pennation angle and thickness of the rectus femoris and subcutaneous layer of the thigh were measured via ultrasound im...