Ulnar claw HP:0001178 An abnormal hand position characterized by hyperextension of the fourth and fifth fingers at the metacarpophalangeal joints and flexion of the interphalangeal joints of the same fingers such that they are curled towards the palm. An ulnar claw, also known as claw hand, is an abnormal hand position that is associated with lesions of the ulnar nerve. Note that ulnar claw is to be distinguished from ectrodactyly, which also can be referred to as claw hand. UMLS:C4025799 Abnormal hand morphology