C h a p t e r 2 0 Lacertus Syndrome: Median Nerve Release at the Elbow

Abstract

Lacertus syndrome is characterized by compression of the median nerve under the lacertus fibrosus (bicipital aponeurosis) at the elbow. You can easily release this with good results in the right patients, as described in Clip 20-1. It is a simple procedure, similar to carpal tunnel release with WALANT. You make the diagnosis of lacertus syndrome on a clinical examination triad consisting of: 1. Weakness in the flexor carpi radialis (FCR), flexor pollicis longus (FPL), and flexor digitorum profundus muscles of the index finger (FDP2) 2. Pain over the median nerve at the medial edge of the lacertus fibrosus 1 3. A positive scratch collapse test over the median nerve at the elbow Clip 20-2 demonstrates clinical examination of lacertus syndrome showing weakness of FCR, FDP2, FPL, tenderness under lacertus fibrosis, and posi-tive scratch collapse test. • Although less prominent than motor signs, sensory symptoms in the median nerve distribution are present in some patients, especially in the palmar cutaneous branch distribution. • Consider this diagnosis if patients complain of weakness or numbness in the palmar cutaneous distribution, or after failed carpal tunnel release. • You will not make this diagnosis with nerve conduction studies. You make the diagnosis of lacertus syndrome through a history and a thor-ough physical motor examination. 2 ADVANTAGES OF WALANT VERSUS SEDATION AND TOURNIQUET IN MEDIAN NERVE RELEASE AT THE ELBOW • You can see that you have solved your patient's problem by watching him get the power back to his FPL, FDP2, and FCR on the operating table before you close the skin, as shown in four videos in this chapter. • Your patient can see that you have solved his problem when he watches power return to his FPL, FDP2, and FCR on the operating table.