Study on variations in the palmar cutaneous branch of median nerve

Abstract

Introduction: Variations in the anatomy of nerves at wrist have been recognised to be of importance to surgeon. Attention has been called for injury to palmar cutaneous branch of median nerve as a cause of the painful dysesthesia that follows carpal tunnel surgery.A comprehensive evaluation in wrist region is essential to avoid complications. Objective: In present study the objective was to study the anatomic variationsin number and side of origin of palmar cutaneous branch from median nerve. Materials and Methods: The study included 51 hands from human cadavers at Department of Anatomy, Mysore Medical College and Research Institute, Mysore during the time period of 2011-13. The specimens were fixed in 10% formalin, finely dissected and the numbers and side of origin were noted. Results: The palmar cutaneous branch was present in all 51 specimens and it was located under the tendons of palmaris longus and flexor carpi radialis. The palmar cutaneous branch of median nerve was single in 46 specimens (90.18%) and in 5 specimens it was observed to be multiple (9.8%). In 50 specimens the palmar cutaneous branches originated from radial side of the median nerve (98.04%) and in only one specimen (1.96%) it originated on ulnar side of the median nerve. Conclusion: A key to carry out therapeutic and diagnostic procedures successfully on carpal tunnel depends on the knowledge of the possible variations of nerves which may be encountered. Such variations are not only more prone to iatrogenic injuries but they interfere in the correct interpretation of clinical conditions as well.