Muscle belly in the tunnel: an unusual cause of carpal tunnel syndrome in a patient with spinal cord injury

Carpal tunnel syndrome is a common nerve issue in the wrist, especially for people with spinal cord injuries who use wheelchairs. This case report highlights an unusual cause: a muscle belly encroaching the median nerve within the carpal tunnel. A wheelchair basketball player with a spinal cord injury experienced hand numbness. An ultrasound revealed an abnormal muscle in the carpal tunnel, causing the nerve compression. Identifying the cause of carpal tunnel syndrome is crucial for individuals with spinal cord injuries as they heavily rely on their arms for daily activities.

• 1
  An aberrant muscle belly of the flexor digitorum superficialis of the index finger was found to be compressing the median nerve in the carpal tunnel of a patient with a spinal cord injury.
• 2
  Dynamic imaging confirmed the entrapment of the median nerve with flexion of the index finger.
• 3
  The patient had previously undergone carpal tunnel release surgery without complete relief, suggesting aberrant muscles can be a cause of recurrence.