This review describes a series of experiments in which sarcomere length was measured in human wrist muscles to understand their design. Sarcomere length measurements were combined with studies on cadaveric extremities to generate biomechanical models of human wrist function and to provide insights into the mechanism by which wrist strength balance is achieved. Intraoperative measurements of the...

OBJECTIVE Analize data on patients submitted to transfer of the pronator teres (PT) or the flexor carpi ulnaris (FCB) to the extensor carpi radialis longus/brevis (ECRL/B) in order to correct flexed wrist deformity in patients with cerebral palsy. METHOD Patients were divided into two groups: PT group and FCU group to ECRL/B. The results were evaluated by goniometry and by the functional hand...

The aim of the study was to compare the theoretical indicator of upper limb load with the physiological indicator of musculoskeletal load, which is present while performing a repetitive task (a normalized electromyography [EMG] amplitude recorded from the muscles of the upper limb involved in the performed task). In an experimental study of a repetitive task, the EMG signal from 5 main muscles ...

Human subjects performed step-tracking movements of the wrist in the radial direction. Movement amplitude, external load, and accuracy instructions were varied. We used surface electrodes to record muscle activity from an agonist, extensor carpi radialis longus, and an antagonist, extensor carpi ulnaris. When subjects performed movements “as fast as possible” that were opposed by different exte...

In many species of frog, the forelimb muscles important in amplexus are known to be much larger in males than in females. We studied this dimorphism in three forelimb muscles in the bullfrog [abductor indicus longus (AIL), flexor carpi radialis (FCR) and extensor carpi radialis (ECR)] by testing their isometric contractile properties. One muscle that is not dimorphic, the extensor carpi ulnaris...

The aims of this study were to explore muscle activity levels during different violin repertoires, quantify the general bilaterally in upper extremity muscles, and evaluate associations between anthropometrics characteristics. In 18 skilled players surface EMG was recorded from trapezius (UT), flexor digitorum superficialis (FDS), extensor carpi ulnaris (ECU), cummunis (EDC), radialis (ECR) A E...

BACKGROUND On the one hand, stimulating the motor cortex at different spots may activate the same muscle and result in a muscle-specific cortical map. Maps of different muscles, which are functionally coupled, may present with a large overlap but may also show a relevant variability. On the other hand, stimulation of the motor cortex at one spot with different stimulation intensities results in...

Avulsion fractures of the radial wrist extensor from the metacarpal base are rare injuries, and have previously been reported in only a few papers. Although 2 cases of closed rupture of the extensor carpi ulnaris (ECU) were mentioned in 1 report, no case of avulsion fracture of the ECU from its insertion was found in the literature. We recently encountered such a case. The patient, a machine op...

Extraarticular pigmented villonodular synovitis (PVNS) is very rare in the distal forearm. There has only been one previous case report of this disease in the extensor tendons of a child. We report a case of PVNS of the distal forearm that presented as two nodules over the radial aspect and a separate nodule on the ulnar aspect beneath the flexor carpi ulnaris tendon. Surgical exploration revea...

BACKGROUND Previous studies have indicated that the demands placed on the medial ulnar collateral ligament of the elbow when it is subjected to valgus torque during throwing exceed its failure strength, which suggests the necessary dynamic contribution of muscle forces. We hypothesized that the flexor-pronator mass assists the medial ulnar collateral ligament in stabilizing the elbow against va...