Cutaneous nerves at risk during the posterior midline approach to the elbow.

The purpose of this study was to investigate the cutaneous nerves at risk during the posterior midline approach to the elbow and proximal ulna. Ten fresh frozen cadaver upper extremities were used for this study. A posterior midline skin incision extending from 10 cm proximal to 15 cm distal to the olecranon tip was created. All superficial nerves were identified and preserved. Nerve diameters were measured, their distance from the olecranon tip assessed, and they were dissected proximally to confirm their nerve of origin. Point of nerve arborization to skin from the midline incision was quantified. An average of one confirmed nerve proximal and five distal to the olecranon tip were identified with an average diameter of 0.9 mm proximal and 1.3 mm distal to the olecranon. The largest nerves were typically located 2 cm proximal (range 7-46 mm) and 45 mm distal (range 9-135 mm) to the olecranon. The branches arborized into the skin an average of 5.2 mm lateral to the incision. All nerves joined the posterior medial antebrachial cutaneous nerve. The branches of the medial antebrachial cutaneous nerve are at risk with a straight posterior midline elbow incision, though the clinical significance of injury to these nerves at this location is unknown.