Presentation
Bilateral wrist and hand pain for about 10 to 15 years. Recent onset of the right wrist radial side pain with difficulty in thumb movements. No trauma.
Patient Data
Loss of the thenar eminence on both sides.
Just proximal to the right carpal tunnel, there is diffuse edema and hypoechogenicity of the median nerve with a cross-sectional area of about 30 mm2. The superficial most thenar muscle shows fatty infiltration and volume loss. The retinaculum of the right 1st extensor compartment is thickened with a common synovial sheath of abductor pollicis longus and extensor pollicis brevis up to the distal end radius.
The left median nerve shows similar findings with a cross-sectional area of about 38 mm2 just proximal to the carpal tunnel.
Case Discussion
A female presented with long-term bilateral hand-wrist pain. Loss of bilateral thenar eminence favors muscle atrophy due to carpal tunnel syndrome. The ultrasound shows a notch sign of carpal tunnel syndrome bilaterally. Recent right thumb painful movements are due to De Quervain tenosynovitis.
When the median nerve edema is distal to the carpal tunnel, it is known as an inverted notch sign.