Asked by FCU
Ulnar nerve injury results in clawing of hands. Clawing is characterized by:
- Hyperextension of MCP joints: Unopposed action of extensors (lumbricals paralyzed)
- Injury at wrist (lower level):
- FDP spared: Flexion of IPJ (more clawing visually)
- Injury at elbow (higher level):
- FDP injured: No flexion of IPJ (less clawing visually)
Lesions at the elbow often have less clawing, since the ulnar half of FDP is paralyzed. This phenomenon is known as ulnar paradox.
