Reconstruction of Thumb and Index Flexion in High Median Nerve Paralysis Using a Single Radial Wrist Extensor Tendon Transfer.

Abstract

Chronic paralysis of the flexor pollicis longus (FPL) and the index flexor digitorum profundus (FDP) is commonly treated with brachioradialis transfer to the FPL and side-to-side suturing of the index FDP to the FDPs of the ulnar digits. We report the clinical outcomes of nine patients in whom the extensor carpi radialis brevis (ECRB) or longus (ECRL) was transferred to both the FPL and index FDP. We reviewed nine patients who underwent tendon transfer of the ECRB/L to both the FPL and index FDP. Postoperative assessments included strength grading of the FPL and index FDP using the Medical Research Council (MRC) scale, range of motion, and key pinch strength. The follow-up ranged from 4 to 58 months. Flexor pollicis longus and index FDP paralysis resulted from traumatic high median nerve injuries (n = 4), infraclavicular brachial plexus injuries (n = 3), Parsonage-Turner syndrome (n = 1), and neurofibromatosis type 2 (n = 1). All nine patients regained full thumb range of motion with MRC grade 4 strength. Seven patients achieved full active and passive range of motion of the index finger, although one required a secondary procedure to adjust index FDP tension. All patients had MRC grade 4 strength at the index distal interphalangeal joint. The mean key pinch strength was 3.4 kg, approximately 40% of the contralateral hand. Tendon transfer of ECRB/L to both the FPL and index FDP is a viable surgical alternative for restoring thumb and index finger flexion. Therapeutic V.