Should full threaded compression screws be used in adult femoral neck fractures?

INTRODUCTION: Operative treatment consisting of fracture reduction and fixation, or arthroplasty to permit early patient mobilization, continues to be the treatment of choice for most femoral neck fractures. Options for internal fixation have included a variety of implants; however most recent reports and textbooks cite parallel multiple cancellous screws as the surgical technique of choice.

METHODS: The study was prospective, randomized and IRB approved. Inclusion criteria included skeletal maturity, closed femoral neck fracture without concomitant fractures or injuries with complete charts and adequate radiographs obtained from the initial injury till the last follow-up. Forty-four patients were enrolled in this study during one-year period at two university centers. 22 were randomized to be treated with full threaded, cannulated compression screws (Acutrak 6/7, ACUMED) (Group 1) and the other 22 with 16mm partial threaded, 6.5mm or 7.3mm cannulated screws (SYNTHES) (Group 2). Three or four screws were used in both groups according to fracture type and surgeon's preference. Data evaluated included surgical time, fluoroscopy time, fracture type, radiological outcome, complications and functional status using the Harris Hip Score.

RESULTS: Both groups were comparable in terms of age and gender. There was not a significant difference in terms of surgical time, follow-up period, fracture type, or fluoroscopy time. There were eight complications in Group 1 and two in Group 2 (P=0.049) Time to union was significantly longer in Group 1 (P=0.001). However, Hip Scores were not significantly different in both groups (P=0.20).

CONCLUSION: When compared with full threaded compression screws, partial-threaded cannulated screws provides a shorter union time and less complication rate while providing equivalent functional results in adult femoral neck fractures.