Supernumerary Head of the Biceps Brachii Muscle: Physical Therapy Considerations for Musculocutaneous Nerve Entrapment
Justin Behnke
Co-Presenters: Thomas Koc
College: The College of Health Professions and Human Services
Major: Physical Therapy (DPT)
Faculty Research Mentor: Thomas Koc
Abstract:
Anatomical variations are crucial considerations for Physical Therapists when evaluating and managing neuromuscular dysfunctions. The anterior compartment of the arm typically consists of the biceps brachii, coracobrachialis, and brachialis. A supernumerary head of the biceps brachii occurs in 7.5% to 18.3% of individuals. This case report examines a supernumerary head of the biceps that was identified in an adult female human (cadaveric) donor and explores its clinical implications, particularly its potential role in musculocutaneous nerve entrapment and double crush syndrome.Although isolated musculocutaneous nerve injuries are rare, anatomical variations can increase the risk of nerve entrapment. A supernumerary biceps head may serve as a proximal entrapment site, predisposing the nerve to further compression distally, as seen in conditions like carpal tunnel syndrome and cervical radiculopathy. Physical therapy interventions should incorporate targeted neurodynamic techniques, including nerve sliders, gliders, and tensioners, to enhance nerve mobility and adaptability. Additionally, manual therapy, postural education, flexibility, and strengthening exercises can optimize nerve function and prevent symptom progression.By integrating neurodynamic principles with comprehensive rehabilitation strategies, physical therapists can improve patient outcomes in cases of musculocutaneous nerve dysfunction. This report highlights the importance of considering anatomical variations during clinical examination and treatment planning.Word count 197Keywords:Biceps brachii variation, musculocutaneous nerve entrapment, double crush syndrome, neurodynamic techniques, physical therapy