Lacertus Fibrosus Syndrome: A Case Report

Abstract

Lacertus fibrosus syndrome is described as compression of the median nerve, which takes place beneath a layer of ligamentous tissue (lacertus fibrosus, also known as bicipital aponeurosis) slightly beyond the elbow joint. Both sexes can develop lacertus fibrosus syndrome, most often after the age of 35. The possible risk factors are repetition of movements, overwork, and manual work while the forearm is pronated. Lacertus fibrosus syndrome presents a distinct diagnostic challenge because it is a somewhat unknown and nondocumented disease. Its symptoms are often mistaken for those of carpal tunnel syndrome, which complicates the differential diagnosis and management of the patient. All patients who report tingling, numbness, loss of strength, muscle loss, manual endurance, or dexterity should be investigated and tested for both carpal tunnel syndrome and lacertus syndrome. Here, a case of a 43-year-old woman is discussed, who presented with chief complaints of pain and tingling sensation in the left upper limb, which was associated with loss of thumb pinch grip. The pain was aggravated with elbow extension and relieved with rest. The patient underwent left elbow median nerve decompression and was discharged in steady condition. This case report highlights the accurate clinical presentation and surgical intervention for the syndrome, for which the outcome turned out to be satisfying.

Three-Headed Biceps Brachii Muscle: A Rare Site of Proximal Median Nerve Entrapment

“…The two heads of the biceps brachii converge to form a single common tendon that attaches to the radial tuberosity. Additionally, there are aponeurotic fibers derived from the tendon, termed "bicipital aponeurosis" (BA) (lacertus fibrosus [1]), that extends medially and inferiorly to blend with the antebrachial fascia over the superficial layer of forearm flexors. The biceps brachii is innervated by the musculocutaneous nerve, and the main actions are supination and flexion of the elbow, with the short head of biceps brachii aiding in adduction and flexion of the shoulder joint [2].…”