Accurate Determination of the Sites of the Distal Hole of the Humeral Interlocking Intramedullary Nail Using Monofilament Solid Core Optical Fiber

Abstract

This prospective study was conducted in order to evaluate the results of using the monofilament solid core optical fiber for the accurate determination of the site of the distal hole of the humeral interlocking intramedullary nail. Seven patients with fresh humeral fractures treated with humeral interlocking intramedullary nailing from April 2005 to May 2007 were evaluated. The minimum follow-up period was 12 months. We analyzed type of humeral fracture, time of technique, length of the incision, and Radiation exposure. All cases were treated with one distal locking screw during interlocking intramedullary nailing. The technique is based on the semitransparency of the bone tissue. The system is composed of 2 parts: light source and monofilament solid core optical fiber. Description of the technique:- After reduction of the fracture and assembly of the nail, a mechanical measure is taken to determine the expected site of the distal locking holes of the interlocking nail and site of skin incision, then a longitudinal skin incision is made and the soft tissue is dissected until the bone is reached, then the optical fiber is introduced until its tip reaches the distal hole and adjusted to concentrate the light on the nail hole.

At this time an illuminated ellipse appears on the anterior cortex of the bone. The drill bit is adjusted to the center of this ellipse then the drilling is started. After piercing of the nearby cortex a 3.5 mm suction handle is introduced in the bone hole to suck the blood then physical and mechanical checks are done after which the far cortex is drilled. The results show that the site of the distal hole of the humeral interlocking intramedullary nail could be detected successfully in all cases with no radiation exposure. As a conclusion; we can say that Monofilament solid core optical fiber can be used successfully for the accurate determination of the site of the distal hole of the humeral interlocking intramedullary nail. For satisfactory results, accurate technique and experience of the operator were required.