Anconeus Muscle - Innervation

Innervation

Anconeus is innervated by the radial nerve (cervical roots 7 and 8) from the posterior cord of the brachial plexus. The somatomotor portion of radial nerve innervating anconeus bifurcates from the main branch in the radial groove of the humerus. This innervation pattern follows the rules of innervation of the musculature of the posterior forearm (extensor) compartment by the radial nerve.

Pathology: Trauma to the anconeus muscle can usually result from a shoulder dislocation or fractures of the upper part of the humerus or around the olecranon, or any injury that damages the radial nerve. Harm inflicted upon the radial nerve through these mechanisms can paralyze the anconeus muscle as well as other extensors of the elbow and wrist. There are no specific acquired injuries that exclusively affect the anconeus muscle; however, any disease that compromises muscular functions, particularly arm extension (i.e. muscular dystrophy) will affect this particular accessory muscle. Heterotrophic ossification can result from certain trauma as it is an abnormal growth of osseous tissue in non-osseous tissue (e.g. muscle tissue). The condition is usually found in the hips, although there have been documented cases of certain individuals with it occurring in the arms and legs. The cause for the process to initiate is not well understood, only that it typically results from surgery or trauma.