Published online Jul 18, 2013. doi: 10.5312/wjo.v4.i3.130
Revised: April 15, 2013
Accepted: June 1, 2013
Published online: July 18, 2013
Core tip: Limitations of intramedullary nailing (IMN) of the ulna, which make IMN a secondary choice, include problems experienced at the proximal interlocking screw (PIS). A new PIS system may solve most common problems with an eccentrically aligned screw. This new PIS system may be very advantageous if the fluoroscopy time, operation time and the need for additional incision in other systems is considered. However, the screw must be designed at a safe angle to have these advantages. According to our results, a 20.0° is the optimum angle of alignment for this screw.