MRN findings of lateral antebrachial cutaneous nerve impingement in a collegiate athlete

A Rare Cause of Lateral Antebrachial Cutaneous Neuropathy Secondary to Internal Fixation of a Supracondylar Humeral Fracture: A Case Report

CASE

We discuss a patient with a 6-month history of episodic elbow and forearm pain 6 years after supracondylar humeral fracture fixed with Steinmann pins at the age of 10 years and 5-year follow-up data at the age of 21 years. Electrodiagnostic studies exhibited no response from the lateral antebrachial cutaneous (LABC) nerve, and anesthetic injection demonstrated relief. Surgical intervention provided immediate relief of symptoms without recurrence for 5 years postsurgery.

CONCLUSION

Atypical LABC neuromas can be found after operative fixation of supracondylar humerus fractures. Neuroma excision and intramuscular burying of affected nerve ends remains a viable treatment option for patients with late-presenting traumatic neuromas.

Axillary and musculocutaneous neuropathies

This chapter covers axillary and musculocutaneous neuropathies, with a focus on clinically relevant anatomy, electrodiagnostic approaches, etiologic considerations, and management principles. Disorders of the lateral antebrachial cutaneous nerve, a derivative of the musculocutaneous nerve, are also reviewed. We emphasize the importance of objective findings, including the physical examination and electrodiagnostic evaluation in confirming the isolated involvement of each nerve which, along with the clinical history, informs etiologic considerations. Axillary and musculocutaneous neuropathies are both rare in isolation and most frequently occur in the setting of trauma. Less commonly encountered etiologies include external compression or entrapment, neoplastic involvement, or immune-mediated disorders including neuralgic amyotrophy, postsurgical inflammatory neuropathy, multifocal motor neuropathy, vasculitic neuropathy, and multifocal chronic inflammatory demyelinating polyradiculoneuropathy.

Lacertus syndrome: Use of pre- and post-exercise MRI to aid in diagnosis and treatment

Lacertus syndrome is a chronic exertional compartment syndrome of the forearm that is unlike exertional compartment syndrome of the lower extremity. It differs from traditional exertional compartment syndrome in terms of the anatomy, symptoms and physical exam findings. This is a case where dynamic magnetic resonance imaging is used to confirm the diagnosis rather than relying solely on a clinical diagnosis or invasive compartment pressure monitoring. Surgical release of the lacertus fibrosis can effectively relieve the pressure over the pronator and allow the patient to resume previous activities.