Claw deformity is most associated with injury to which nerve?

Study for the NBCOT Hand Injuries and Intervention Test. Prepare with flashcards and multiple choice questions, each question offers hints and explanations. Get ready for success!

Claw deformity stems from loss of intrinsic hand muscle function, which normally coordinates finger flexion and extension. The ulnar nerve supplies most of those intrinsic muscles, especially the interossei and the medial two lumbricals. When the distal ulnar nerve is injured, these intrinsic muscles can no longer flex the metacarpophalangeal joints and extend the interphalangeal joints. As a result, the extensor digitorum tends to hyperextend the MCP joints while the flexors of the fingers pull the IP joints into flexion, producing the characteristic clawing, most evident in the ring and little fingers. Other nerves produce different patterns of hand weakness (median nerve injury leading to hand of benediction, radial nerve causing wrist drop, musculocutaneous affecting elbow flexion), but claw deformity is classically linked to distal ulnar nerve injury.