TREATMENT OF TYPE-II, IIIA, AND IIIB OPEN FRACTURES OF THE TIBIAL SHAFT - A PROSPECTIVE COMPARISON OF UNREAMED INTERLOCKING INTRAMEDULLARY NAILS AND HALF-PIN EXTERNAL FIXATORS

Objective: To compare unreamed intramedullary nailing (IMN) with exter nal fixation (EF) in patients with Type IT, IIIA, and IIIB open fractu res of the tibial shaft. Design: An inception cohort of consecutive pa tients with Type II, IIIA, and IIIB tibial fractures incurred between January 1988 and March 1993 were systematically allocated into one of two treatment groups. Patients were treated and followed with a prospe ctively designed protocol. Patients and Setting: All patients were ske letally mature and had incurred a fracture of the tibial diaphysis wit hin twenty-four hours of presentation to the tertiary care hospital, a Level I Trauma Center, One hundred seventy-four fractures in 168 pati ents were stabilized with either IMN (104) or half-pin EF (70). There were 132 men and thirty-six women, with an average age of thirty-three years (range, 14 to 77 years). Intervention: Except for the selection of the fixation device, open fracture care was similar in the two tre atment groups. All patients underwent emergent irrigation and debridem ent with concomitant skeletal stabilization. Cephalosporin antibiotics were administered perioperatively for twenty-four to forty-eight hour s. No wounds were closed primarily. Delayed primary closure, skin graf ting, and/or myoplasty were performed between three and ten days after injury. Main Outcome Measures: The main outcome measures were final f racture alignment, presence of infection or inflammation, hardware fai lure, time to union, and the number of operative procedures. Results: The IMN group had significantly fewer incidences of malalignment than did the EF group [8 vs. 31 percent; p = 0.00005; confidence interval ( CI) = 0.18, 0.76] and had significantly fewer subsequent procedures (m ean of 1.7 vs. mean of 2.7 per fracture; p = 0.001; CI = 0.45, 1.59). IMN resulted in fewer infections/inflammatory problems than did EF at the injury site (13 vs. 21 percent; p = 0.73; CI = -0.63, 0.45) and si gnificantly fewer at surgical interfaces (i.e., pin sites, nail and in terlocking screw insertion sites; 2 vs. 50 percent;p = 0.000; CI = 0.3 9, 0.60). No significant difference was found in the healing rates for the two implant groups. The more severe Gustilo injury types had long er healing times regardless of the type of fixation. Conclusions: Resu lts suggest that unreamed interlocking intramedullary nails are more e fficacious than half-pin external fixators, in particular with regard to maintenance of limb alignment. However, the severity of soft tissue injury rather than the choice of implant appears to be the predominan t factor influencing rapidity of bone healing and rate of injury site infection.