Morphology and innervation of brachioradialis and flexor carpi radialis and their utility in tendon transfer surgeries: A Cadaveric Study

Introduction: The Brachioradialis (BR) muscle flap is easy to harvest, provides a stable coverage to the cubital fossa as it is well vascularized. The BR andflexor carpi radialis (FCR) tendons are utilized in tendon transfer to restore the normal hand function. Therefore, the present study describes the morphology of the muscle bellies and the tendons of BR and FCR along with their pattern of innervation.

Materials and methods: The study was carried out on 27 upper limbs of formalin-fixed, adult human cadavers. Length and width of the bellies of BR and FCR were measured. The number of motor branches and their distances from the bi-epicondylar line was measured.

Results: The mean lengths of BR and FCR bellies were 21.22±2.18cm and 16.15±2.39cm, and the lengths of their tendons were, 12.67±1.13cm and 12.48±1.72cm respectively. BR received a single motor branch in 19 upper limbs. However, FCR received single motor branch in 25 limbs as a common trunk. One upper limb received three motor branches to BR, and two upper limbs received two motor branches to FCR. The most proximal and distal branches to the BR were ranged between 6.3-2.2cm proximal to the bi-epicondylar line. Those to the FCR were ranged between 3.5-6.9cm distal to the bi-epicondylar line.

Conclusion: The motor branches to the BR and FCR are variable in their origin, and the knowledge of such variations is essential for identifying them while performing selective neurotomy surgeries.