Ulnar neuropathy
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Joseph Nasr, M.D.[2]
Overview
Ulnar neuropathy is a peripheral nerve disorder involving dysfunction of the ulnar nerve, most commonly due to compression or ischemia at the elbow (cubital tunnel) or wrist (Guyon canal). It presents with sensory disturbances in the fourth and fifth digits and weakness of intrinsic hand muscles. Ulnar neuropathy occurs with increased frequency in patients undergoing long-term hemodialysis.
Causes
Common causes of ulnar neuropathy include:
- Prolonged or repetitive elbow flexion and external compression
- Entrapment at the cubital tunnel or Guyon canal
- Trauma or repetitive mechanical stress
- Metabolic and systemic conditions causing nerve vulnerability
In patients undergoing hemodialysis, additional contributing mechanisms include prolonged arm positioning during dialysis sessions, arteriovenous access–related alterations in blood flow, and dialysis-related amyloid deposition.[1]
Clinical features[1]
Clinical manifestations may include:
- Numbness and paresthesia of the fourth and fifth digits
- Medial hand pain
- Weakness of finger abduction and adduction
- Loss of grip strength
- Atrophy of the first dorsal interosseous muscle in advanced cases
- Development of ulnar claw hand in severe or chronic disease
Symptoms may be unilateral or bilateral and can progress gradually.
Diagnosis[1]
Diagnosis is based on clinical examination demonstrating sensory and motor deficits in the ulnar nerve distribution. Electromyography and nerve conduction studies are used to confirm the diagnosis and localize the site of nerve involvement.
In hemodialysis patients, ulnar neuropathy should be differentiated from access-related hand ischemia and ischemic monomelic neuropathy, which present with ischemic features or acute global neurologic deficits.
Management[1]
Initial management is typically conservative and includes activity modification, avoidance of prolonged elbow flexion or pressure, and physical therapy. Splinting or padding may be beneficial.
Surgical decompression may be considered in patients with persistent symptoms, progressive weakness, or evidence of severe nerve compression on electrodiagnostic testing.
References
- ↑ 1.0 1.1 1.2 1.3 Nardin R, Chapman KM, Raynor EM. Prevalence of ulnar neuropathy in patients receiving hemodialysis. Arch Neurol. 2005;62(2): 271-275. doi:10.1001/archneur.62.2.271