Superficial branch of the radial nerve in adult cadavers; course and branching pattern

Aim: It is important to have a good understanding of the anatomy and topography of the superficial branch of the radial nerve (SBRN), which is one of the two terminal branches of the radial nerve, in order to avoid overlooking rare diseases, complications in the surgery of this region etc. The aim of this study is to investigate the course, branching pattern, and relationship of SBRN with adjacent structures to provide insights to clinical physicians and especially surgeons. Materials and Methods: The study was conducted on 20 upper extremities (11 adult cadavers; 5 male, 6 female) fixed with formaldehyde, ethanol and glycerol solution in the laboratory of Istanbul University-Cerrahpasa, Cerrahpasa Faculty of Medicine, Department of Anatomy. The distances between the points where SBRN surfaces and branches to the fixed bony landmarks were measured and recorded. The measurements were evaluated using statistical methods. Results: All upper extremities used in our study were included in the Type 1 group. The level where SBRN separated from the radial nerve was distal to the biepicondylar line in 13 (65%) cases and proximal to this line in 7 cases (35%). In all cases, SBRN coursed deep to the m. brachioradialis and superficial to the m. extensor carpi radialis longus and became superficial approximately 7,37 cm proximal to the radial styloid process (RSP). On all sides, the nerve progressed slightly distally in the superficial fascia and divided into medial and lateral branches at an average of 4,20 cm proximal to the RSP. The lateral branch (SBRN-3) reached the lateral aspect of the thumb and thenar eminence, while the medial branch bifurcated to innervate the first dorsal web (SBRN-2) and extend distally to the middle phalanges of the index and middle finger (SBRN-1). Conclusion: In this study, which had similar results as the previous literature, did not encounter any rare variations. We believe that these data will assist clinicians in both diagnosis and treatment as well as in preventing complications.