The technique of restoring extension of the hand and fingers is described in an inveterate injury of the brachial plexus. The insertion of m. flexor carpi ulnaris was transferred with an intact nervous and vascular supply to different tendons of the m. extensor digitorum closely above the retinaculum extensorum. The muscle strength was 4-using Janda’s muscle test. Dorsal flexion of the hand was possible from the basic position, with extension of the fingers to their full extent. Anatomical investigation revealed that the mean length of the caput humerale m. flexor carpi ulnaris is 26.5 cm, the number of final nerve branches 2–3, the mean length of the nerves varies between 1.3–2.3 cm, the vascular supply is in 90 % directly from the ulnar artery. In 10 % of dissections the vascular supply is from the anterior ulnar recurrent artery. The length of the vascular bundle is 3.2 cm. In 10 % of upper extremities examined an additional vascular bundle was present which was 2 cm distal from the main hilus, also from the a. ulnaris. The pattern of the neurovascular supply is no impediment for the transposition of the insertion tendon into the regio antebrachii posterior. The transfer of the insertion tendon of the m. flexor carpi ulnaris in inveterate injuries of the brachial plexus is a useful alternative for the reconstruction of nerves to restore the extension of the hand and fingers.

        Key words: reconstruction of elbow flexion, reconstruction of wrist extension, transposition of pedicled muscles, flexor carpi ulnaris muscle