Eur J Anat, 16 (3): 184-189 (2012)

A new straight proximal humeral nail: a cadaveric study of itsanatomical relationships

Javier García-Coiradas¹, Marc Rodríguez-Niedenführ², Yaiza Lópiz¹,Carlos García-Fernandez¹, José R. Sañudo², Teresa Vázquez^2*, Fernando Marco¹

¹Shoulder and Elbow Unit, Department of Orthopedics, Hospital Clínico San Carlos, Complutense University, Madrid, Spain ²Department of Human Anatomy and Embryology I, School of Medicine, Complutense University, Madrid, Spain

ABSTRACT New humeral nailing systems appear constantly in the market, but few anatomical studies assessing the potential risks of neurovascular injury, exist. The aim of this study is to determine the potential risk of neurovascular injury during proximal and distal locking. An anatomical analysis was carried out in cadavers where a new straight proximal humeral nail had been inserted. The nail entry point was always located medially to the myotendinous junction of the supraspinatus muscle, therefore affecting only muscle fibres. The nail entry point was surrounded by articular cartilage of the humeral head. The axillary nerve and the posterior humeral circumflex artery were at safe distances (>2cm) from all proximal and distal locking screws. The radial nerve and its accompanying artery, the profunda brachii artery, were at risk whenever medial cortex violation happened, as they were located within 1cm of the exit point of the most distal locking screw. The straight humeral nail analysed in the current study seems to be more secure in relation to the neurovascular injury potential when compared to previously reported ones. Only the incorrect selection of the length of the most distal locking screw may lead to injury of the radial nerve and/or profunda brachii artery; therefore, close monitorisation during the insertion of this distal locking screw is recommended.

Keywords: Shoulder, Fractures, Fixation, Neurovascular injury