Brachioradialis to Extensor Carpi Ulnaris Transfer – An Additional Transfer to Prevent Radial Deviation Deformity of the Wrist following Tendon Transfers for Posterior Interosseous Nerve Palsy

The usual recommendation in posterior interosseous nerve (PIN) palsy is to use the flexor carpi radialis instead of the flexor carpi ulnaris (FCU) for restoration of digital extension. The use of FCU takes away the only remaining ulnar deviator of the wrist. Although preserving the FCU prevents severe radial deviation deformity, we found that some patients still develop a radial deviation deformity, especially during wrist extension. We have used a brachioradialis (BR) to extensor carpi ulnaris (ECU) transfer to prevent the development of a radial deviation deformity and find that it restores the normal radio-ulnar balance of the wrist by providing a dynamic ulnar stabiliser. It is a simple addition to the standard two tendon transfers for PIN palsy with minimal donor morbidity. We have used this triple transfer for PIN palsy in seven patients with satisfactory results and no complications. Level of Evidence: Level V (Therapeutic)