Outcomes and Complications of Tendon Transfers to Address Pinch and Grasp Weakness: A Systematic Review of the Operative Management of Ulnar Nerve Paralysis

Abstract

In the hand, the ulnar nerve characteristically innervates the adductor pollicis, deep head of the flexor pollicis brevis, all the interossei, the lumbricals of the ring and small fingers, and the hypothenar muscles-although anatomical variations of innervation have been documented. 1,2 Ulnar nerve paralysis manifests clinically as weakness, deformity, asynchronous motion, and loss of abduction/adduction control. 1 The adductor pollicis and first dorsal interosseous muscles provide up to 75 percent of the adduction force of the thumb, and the intrinsic muscles of the hand account for approximately 50 percent of grip strength. 3 Consequently, following ulnar nerve injury a reduction in pinch strength by up to 83