Electrode placement for isolated thumb extension. The very small negative electrode is placed about two thirds of the way down the forearm over the extensor surface. The positive electrode is over the extensor tendons.
Electrode placement for isolated thumb extension. The very small negative electrode is placed about two thirds of the way down the forearm over the extensor surface. The positive electrode is over the extensor tendons.
Stimulation results in isolated thumb extension, which would be graded three out of five in a muscle grade.
Muscles involved in thumb extension:
Extensor Pollicis Longus
Origin: Middle third of posterior surface of
ulna, interosseous membrane
Insertion: thumb, distal phalanx
Nerves involved in thumb extension:
Extensor Pollicis Longus
Nerve innervation: innervated by the posterior interosseous nerve which is a continuation of the deep branch of the radial nerve after it passes through the supinator muscle
Nerve root: C7, C8