Combined distal nerve and tendon transfer in drop wrist for treatment of high injuries of the radial nerve

Abstract

The aim of direct distal selective nerve transfer close to the end organ with high radial nerve injury is restoration of the paretic function before irreversible atrophy of the target muscle. Simultaneous tendon transfer enables direct functional correction of wrist drop. Selective nerve and tendon transfer of the lower arm is indicated if a)the primary nerve lesion is located proximally distant and reinnervation by direct nerve repair would take too long to reach aparetic muscle because of the long distance involved, b)direct repair of the nerve lesion is impossible or c)there has been a substantial delay after the primary injury. Aviable donor nerve must be available. A) After final denervation of amuscle, which occurs approximately 1.5years after a nerve injury, the atrophy is irreversible and a nerve transfer can no longer restore the paretic muscle. Only younger patients under 30 years old might benefit from delayed nerve transfer. B) When no sufficient donor nerve is available only tendon transfer is possible. Direct nerve transfer from the median nerve to the radial nerve as well as direct functional correction of wrist drop by tendon transfer of the pronator teres muscle. Immobilization of the arm for 3 days, wrist orthosis for 6weeks for protection of the tendon transfer, ergotherapy and physiotherapy preferably by a hand therapist. Active wrist and finger extension 2years after transfer, with individualized extension of the thumb and index finger is possible, wrist drop reversed.