The motor branching of the median nerve in forearm in human fetuses

Median nerve innervates the most of the forearm muscles of the anterior compartment. Surgical procedure, electrical stimulation, injection of botulinum toxin are carried out in the treatment of median nerve injury. The application of these methods especially on the motor entry point of these muscles increases the success of the treatment. The present study is aimed to determine the innervation pattern of the median nerve to the forearm muscles and the locations of the motor nerve entry points in forearm. Twelve forearms of 6 human fetuses (4 female, 2 male) are dissected. Forearms are divided into proximal, intermedial and distal parts equally by horizontal lines and lateral-medial parts by a median line. The muscles that innervated by median nerve are morphologically identified. The relationships between these muscles and the median nerve are examined. The branching pattern of the median nerve to the muscles are determined. The branching pattern of the median nerve to MPT, MFCR, MFDS, MFPoL, MFDS and MPQ are established, and the types of branching patterns for these muscles are 7, 3, 4, 3, 2 and 1 respectively. The motor nerve entry points to the anterior compartment muscles of forearm are determined according to proximal-lateral, proximal-medial, intermedial-lateral, intermedial-medial, distal-lateral and distal?medial parts, and the percentages are 41.1%, 38.9%, 30.1% , 18.3%, 1.4% and 0.7% respectively. As a result, detailed anatomical knowledge about the innervation of the forearm muscles increases the success of the surgery techniques on this region or treatment tecniques like electrotherapy and botulinum toxin injection.