Although paralysis of the posterior interosseous nerve is relatively unusual, there has been over the years a large measure of uncertainty about the nature of the causative lesion. In the literature, there is a paucity of pathologic proof about this disorder. The purpose of this paper is to demonstrate a specific causative lesion capable of producing such paralysis, to elucidate the pathologic processes which are very likely causative in many cases, and to demonstrate the recovery which may follow definitive surgical correction of the offending lesion.
Anatomy and Function
After the radial nerve gives off its branches to the extensor carpi radialis longus and the extensor carpi radialis brevis, it enters the antecubital fossa on its lateral aspect between the biceps and brachialis, medially, and the brachioradialis, laterally. It then divides into a superficial (sensory) branch and a deep, or posterior, interosseous branch, which has a very short course before
WHITELEY WH, ALPERS BJ. Posterior Interosseous Nerve Palsy with Spontaneous Neuroma Formation. AMA Arch Neurol. 1959;1(2):226–229. doi:10.1001/archneur.1959.03840020100012