A Case of Atraumatic Acute Carpal Tunnel Syndrome Requiring Emergency Surgery.

Acute carpal tunnel syndrome (ACTS) is an urgent condition in which symptoms progress rapidly on an hourly basis, and emergency surgery may be required to treat it. ACTS often occurs after a traumatic event such as a fracture of the distal radius, and rarely occurs non-traumatically. We present a case of a 60-year-old male with ACTS secondary to acute synovitis due to rheumatoid arthritis. The patient complained of strong numbness from the thumb to the ring finger and pain in the palm, and he was unable to actively flex or extend his fingers. In addition, severe tenderness was observed in the palm; on the contralateral side, no obvious tenderness of the forearm and wrist joint was observed. Due to the intolerable pain and numbness, ACTS was suspected. Internal pressure from the forearm to the palm was measured, and it was found that the internal pressure of the carpal tunnel was elevated at 150 mmHg. Based on these findings, non-traumatic ACTS was diagnosed, and emergency surgery was performed. The transverse carpal ligament was exposed, an incision was made from the distal end, and the proximal part was fully incised to the forearm fascia so that the carpal tunnel was completely released. The synovial membranes around the median nerve were peeled off, confirming that the nerve had been loosened sufficiently. After the operation, finger pain and numbness improved dramatically from the day after surgery. Proper diagnosis and prompt treatment with surgical median nerve decompression are crucial for good functional recovery in these patients.