Parameters of the ulnar medullary canal for locked intramedullary nailing.

The development of a 'one shot' locked intramedullary device for rapid stabilization of adult ulnar fractures would benefit surgeon and patient alike, but before a prototype device can be manufactured, basic internal measurements of the ulnar medullary canal are needed. Various sections and measurements of 142 adult human cadaver ulnas were performed to determine the calibre, length and curvature of the medullary canal. These measurements revealed that the device can be of one calibre but will need manufactured in three different lengths. Because of the minimal curvature of the ulnar medullary canal and the ability to lock the nail both proximally and distally, the nail can be straight and inserted loosely. A prototype design is described.