Carpal Tunnel Syndrome — ABOS Oral Boards Preparation

A 48-year-old right-hand-dominant female dental hygienist presents to your office with an 18-month history of progressive numbness and tingling in her right hand. Symptoms are worst at night, waking her from sleep, and she finds relief by shaking her hand. Over the past 3 months, she has noticed difficulty with fine motor tasks — buttoning shirts and gripping dental instruments. She has no history of wrist trauma, thyroid disease, diabetes, or inflammatory arthritis. She tried a wrist splint at night for 8 weeks and a corticosteroid injection 4 months ago, both with temporary improvement.

On exam, she has diminished two-point discrimination at 8 mm (normal < 6 mm) in the index and middle fingers. Thenar atrophy is visible compared to the left hand. Tinel sign is positive at the carpal tunnel. Phalen test reproduces symptoms at 15 seconds. Durkan compression test is positive. Grip strength is diminished at 18 kg (compared to 28 kg on the left). Sensation in the dorsal hand and small finger is normal. No Wartenberg sign. Allen test shows normal vascular inflow.

Electrodiagnostic studies confirm severe carpal tunnel syndrome with prolonged distal motor and sensory latencies and reduced thenar motor amplitudes. There is no evidence of cervical radiculopathy or ulnar neuropathy.

You performed a mini-open carpal tunnel release through a 2 cm incision ulnar to the thenar crease. The transverse carpal ligament was divided under direct visualization from distal to proximal. A thickened, fibrotic flexor synovium was noted but no formal synovectomy was performed. The median nerve appeared flattened with a visible hourglass deformity at the distal edge of the ligament. Post-operatively, the patient was placed in a soft dressing with immediate finger and wrist range of motion encouraged.