Radiographic Review of Helical Blade Versus Lag Screw Fixation for Cephalomedullary Nailing of Low-Energy Peritrochanteric Femur Fractures: There is a Difference in Cutout.

OBJECTIVES: To compare the rate of cutout of helical blades and lag screws in low-energy peritrochanteric femur fractures treated with a cephalomedullary nail (CMN).

DESIGN: Retrospective review.

SETTING: Academic medical center.

PATIENTS: Overall, this study included 362 patients with an average age of 83 year old, a majority of whom were women, and had sustained a low-energy peritrochanteric femur fracture treated with a CMN. All patients had at least 3 months of clinical and radiographic follow, with an average follow-up of 11 months and a range of 3-88 months follow-up.

INTERVENTION: Cephalomedullary nailing with the use of a helical blade or single lag screw for proximal fixation.

MAIN OUTCOME MEASUREMENTS: Cutout of the helical blade or lag screw.

RESULTS: Twenty-two cutouts occurred, 14 (15.1%) of 93 patients with helical blades and 8 (3.0%) of 269 patients with lag screws. Cutout with the helical blade was significantly more frequent than with the lag screw (P = 0.0001). The average tip-apex distance (TAD) was significantly greater for those patients who experienced cutout both for the helical blades (23.5 vs. 19.7 mm; P = 0.0194) and lag screws (24.5 vs. 20.0 mm; P = 0.0197). An absolute TAD predictive of cutout could not be determined.

CONCLUSIONS: When the helical blade was used, implant cutout occurred at a significantly higher rate compared with lag screw fixation. There was not a threshold TAD that was predictive of cutout for either implant.

LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.