IATROGENIC POSTERIOR INTEROSSEOUS NERVE INJURY - IS TRANSOSSEOUS STATIC LOCKED NAILING OF THE RADIUS FEASIBLE

To assess the risk of injury to the posterior interosseous nerve (PIN) in transosseous locked nailing of the radius, the relationship of the PIN to the surgical zone was studied in five pairs of fresh frozen ad ult cadaver arms. A static locked intramedullary nail was inserted in each radius using the recommended surgical technique. A formal dissect ion of the radial nerve and its branches was then performed to documen t the relationship of the PIN to the locking screw insertion site. The distance from the PIN to the radial head in neutral, pronation, and s upination also was measured. In no specimen was the PIN injured by the screw insertion. However, in two specimens (right and left arm of the same donor) the PIN was 1 mm and 2 mm, respectively, from the screw i nsertion site. The average shortest distance from the PIN to the screw was 11.3 mm, As measured along the mid-shaft of the radius, the avera ge distance from the radial head to the PIN was 36.2 mm in 90 degrees supination, 46.7 mm in neutral, and 56.9 mm in 90 degrees pronation. T ransosseous static locked nailing of the radius is feasible, but the s urgeon and patient must be aware of the risk of possible injury to the PIN. To minimize this risk, we suggest that the proximal locking scre w should be inserted from a direct lateral entry at <30 mm from the ra dial head with the forearm in neutral rotation.