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Encouraging results of treating femoral trochanteric fractures with specially designed double-screw nails.

BACKGROUND
Conventional intramedullary nails for trochanteric fractures have the disadvantages of intraoperative splintering resulting from large proximal section and postoperative femoral fracture caused by stress concentration at the nail tip. The present study reports the experience of using a specially designed double-screw nail with a smaller proximal section to avoid intraoperative splintering and a longer nail shank to avoid postoperative femoral fracture.


METHODS
Between 2003 and 2005, 144 consecutive femoral trochanteric fractures in 143 patients with an average age of 78.2 years were treated with double-screw nails. The OTA fracture classification was 31-A1 in 51 cases, 31-A2 in 65 cases, and 31-A3 in 28 cases. Seventy-nine patients had more than one major medical disease. The operation was performed using fluoroscopic guide on the fracture table. A distal locking screw was applied in patients with 31-A2 and A3 fractures. At 1 year, 23 patients had died and 6 were lost to follow-up, leaving 114 fractures for functional evaluation.


RESULTS
Patients with 31-A1 fractures tended to have better preoperative conditions than those with 31-A2 and A3 fractures had. The operation time and hospital stay were significantly shorter for those with 31-A1 fractures. Lag screw breakage occurred in four patients with 31-A2 and A3 fractures, and two of these also had screw backout. Another three patients had lag screw cutout. Among these seven patients, only one with screw cutout underwent revision of the fixation. All 114 fractures at 12 months had eventual union. Preoperative mobility was recovered in 35 (85%) patients with 31-A1 fractures and 45 (61%) with 31-A2 and A3 fractures. The functional recovery among patients with 31-A2 and A3 fractures was significantly worse than their preoperative condition and that of patients with 31-A1 fractures.


CONCLUSIONS
The double-screw nail can yield acceptable treatment results for both 31-A1 and 31-A2 and A3 trochanteric fractures and is particularly useful in patients with a small proximal femur. Type 31-A1 and 31-A2 and A3 trochanteric fractures should be separately analyzed in terms of treatment planning or prognostic study.