Palmar Cutaneous Branch of the Median Nerve

  • To assess the palmar cutaneous branch of the median nerve. Examine the sensation in the base of the thenar eminence.
  • Always compare the sensory findings to the opposite uninjured side.
  • Check for scars along the course of the palmar cutaneous branch of the median nerve.
  • Check for a positive Tinel’s sign along the course of the palmar cutaneous branch of the median nerve’
  • Symptoms from a palmar cutaneous branch of the median nerve neuroma can be aggravated by wrist motion, especially dorsiflexion.
  • Neuroma pain weakens grip strength.
Diagrams & Photos
  • Note the palmar cutaneous nerve branch (dash line) and its sensory area (purple circle).
    Note the palmar cutaneous nerve branch (dash line) and its sensory area (purple circle).
  • Examining the sensation in the area of the palmar cutaneous nerve branch of the median nerve (PCBMN).
    Examining the sensation in the area of the palmar cutaneous nerve branch of the median nerve (PCBMN).
Key Points
  • The palmar cutaneous branch of the median nerve is subject to iatrogenic injury during carpal tunnel release or any surgery in the section 9 area between the distal palmaris longus and flexor carpi radialis.
  • Injury to the palmar cutaneous branch of the median nerve can cause a neuroma with resultant pain, paresthesias, and numbness in the base of the thenar eminence.
Grading of Muscle Strength
Exam References
Anatomic Abbreviations
Hand Surgery Resource Exams & Signs Library