Duchenne's Sign (Ulnar Clawing)

Historical Overview

• Guillaume-Benjamin-Amand Duchenne, an early neurologist, first described this sign in 1870.¹

Description

• Also known as a “claw deformity,” Duchenne’s sign affects the ring and little fingers and is characterized by hyperextension of the metacarpophalangeal (MP) joints and flexion of the proximal interphalangeal (PIP) joints.²

Pathophysiology

• Duchenne’s sign arises from low lesions of the ulnar nerve that cause loss of the lumbricals and the dorsal and palmar interosseous muscles that normally flex the MP joints and extend the PIP joints.²

Instructions

• The presence or absence of Duchenne’s sign is determined by examiner observation.

Variations

• Patients may exhibit minor variations in how they present with Duchenne’s sign.

Related Signs and Tests

• Bouvier’s sign
• Jeanne’s sign
• Froment’s sign

Diagnostic Performance Characteristics

• As a clinical sign, Duchenne’s sign is relevant to the medical condition of interest, but its diagnostic performance is often not evaluated in the same way as a diagnostic test. 

• A positive result occurs when the patient exhibits a weak “claw deformity” of the ring and little fingers.

• A negative result occurs when the patient does not exhibit a weak “claw deformity” of the ring and little fingers.

• By testing both the intrinsic and extrinsic ulnar-innervated muscles, the level of injury can be determined.³

1. Plotogea AV, Kereszites A, and Moarcas M. Guillaume-Benjamin-Amand Duchenne - Between Medicine And Art. Bull Transylvania Univ Brasov 2009;6(51):185-8.
2. Doyle JR. Hand and Wrist (Orthopaedic Surgery Essentials Series). Philadelphia: Lippincott Williams & Wilkins, 2006.
3. Culp R and Jacoby SM. Musculoskeletal Examination of the Elbow, Wrist, and Hand: Making the Complex Simple. Thorofare: Slack Inc., 2012.