Study of branching pattern of median nerve at carpal tunnel and its importance in surgical anatomy

Abstract

Introduction: Median nerve is called labourers nerve as it supplies large flexor muscles of forearm and five intrinsic muscles of hand which help in movement of the thumb. Comprehensive knowledge pertaining to its variations is extremely important in clinical and surgical procedures so as to avoid injury to it. The precise knowledge of level of origin of muscular branches of median nerve is essential in free muscular transfers to restore the mobility of fingers after trauma and to prevent the complications during the carpal tunnel decompression. Objective: In present study the objectives are to know the branching pattern of median nerve at carpal tunnel and its variations. Materials and Methods: The study included 51 human cadaver upper limb specimens at the Department of Anatomy, Mysore Medical College and Research Institute, Mysore during 2011-13. The specimens fixed in 10% formalin were finely dissected and median nerve was traced for branching pattern at carpal tunnel. Results: Out of 51 human cadaver specimens, thenar branch of median nerve originated at three different sites, median nerve divided into medial and lateral trunks at different levels with respect to flexor retinaculum, communicating branch between ulnar and median nerve was observed, third lumbrical and adductor pollicis received branches from median nerve. Conclusion: In the present study an attempt is made to know the possible variations of median nerve branching pattern and termination in carpal tunnel so as to provide additional information which may help to decrease the risk of diagnostic and operative complications.