Morphological Variations of Biceps Brachii Muscle in Eastern Indian Population: A Cadaveric Study

Abstract

Background and Aims Biceps brachii (BB) is the commonest muscle in the upper limb showing variations. Supernumerary heads of biceps brachii have been frequently reported in literature. The aim of the present study is to report the occurrence and detailed anatomy of the supernumerary heads of biceps brachii, including its nerve supply among the Eastern Indian population. Materials and Methods A total of 50 upper limbs (25 right and 25 left upper limbs) of embalmed cadavers were dissected and examined for the variation in the origin of BB. Observations Out of 50 upper limbs, five upper limbs (10%) showed supernumerary heads of BB. Inferomedial humeral type of supernumerary head was predominant. A significant percentage (80%) of the supernumerary heads were associated with the nervous variation. Conclusion Biceps muscle is well-known for variation in its origin. Anomalous muscle tear may present as shoulder pain in these patients, magnetic resonance imaging (MRI) may be diagnostic. Detailed anatomy of supernumerary heads serves as a potential tool for graft or flap surgeries with preservation of the function of superior extremities. The awareness of supernumerary heads of biceps brachii in relation to adjacent neurovascular bundles is necessary for modern-day imaging techniques and surgeries.