Effect of lacertus fibrosus release on perineural pressure of the median nerve at the elbow: a cadaveric study

Purpose: The lacertus fibrosus (or bicipital aponeurosis) is a potential site of proximal median neuropathy at the elbow. Lacertus syndrome with motor and/or sensory symptoms has been addressed with a minimally invasive surgical lacertus release. This study evaluates if a lacertus release alters the maximal perineural pressure (Pmax) of the median nerve at the level of the lacertus fibrosus during elbow flexion.

Methods: Seven upper limbs from four fresh cadavers were included. Perineural pressure of the median nerve at the level of the lacertus fibrosus was measured continuously during automated elbow flexions by the biceps brachii muscle.

Results: The mean Pmax before the lacertus release was significantly different than the mean Pmax after the lacertus release (669.15 mmHg vs 77.01 mmHg, p = 0.0180). The mean Pmax after the lacertus release decreased with an average 81.41%.

Conclusion: A simple surgical release of the lacertus fibrosus significantly decreases the maximal perineural pressure of the median nerve at the level of the lacertus fibrosus during elbow flexion.