Cutaneous innervation of the distal forearm and hand - Minimizing complication rate by defining danger zones for surgical approaches.

BACKGROUND: The aim of this study was to investigate the course of the lateral, medial and posterior antebrachial cutaneous nerves, the superficial branch of the radial nerve, the dorsal branch of the ulnar nerve and the palmar branches of the median and ulnar nerve and to determine their relationship to osseous and tendinous landmarks in order to define danger zones for open and arthroscopic approaches in this region.

METHODS: The cutaneous nerves were dissected on 20 embalmed forearms and hands of anatomical specimens. The position and distribution of nerves and landmarks were measured at pre-determined positions. After statistical analysis danger zones were defined.

RESULTS: Based on the course of the subcutaneous nerves, specific danger zones were defined for the palmar, the dorsal, the radial and the ulnar region of the distal forearm, wrist and hand. For the palmar and dorsal regions, specific recommendations for surgical approaches were made, approaches at the ulnar and radial aspect were considered being at high risk for nerve injury.

CONCLUSIONS: The method presented in this study allows the distinction of danger-zones for surgical approaches considering both normal and aberrant courses of cutaneous nerves, including all cutaneous nerves in the distal forearm, wrist and hand. Converting absolute measurements into relative numbers allowed to eliminate proportional differences in morphology and could help guide surgeons to estimate the course of cutaneous nerves in this area, thus helping to avoid iatrogenic nerve injury.