[Efficacy comparison between dynamic hip screw combined with anti-rotation screw and cannulated screw in treating femoral neck fractures].

OBJECTIVE

To compare the curative effect of dynamic hip screw (DHS) combined with anti-rotation screw and cannulated screw in treating patients with Pauwels type II or III femoral neck fracture and to provide the basis for the choice of surgical procedure.

METHODS

Between March 2008 and September 2009, 51 patients with fresh Pauwels type II or III femoral neck fracture were treated with DHS combined with anti-rotation screw (DHS group) and three cannulated screws (cannulated screw group). The DHS group included 23 patients, 13 males and 10 females, aging 27-59 years (mean, 43.2 years); fracture was caused by falling in 1 case, by traffic accident in 17, by falling from height in 5 with a mean time of 27 hours from injury to hospitalization (range, 12-70 hours); and 23 fractures included 9 Pauwels type II and 14 Pauwels type III femoral neck fracture. The cannulated screw group included 28 patients, 12 males and 16 females, aging 20-60 years (mean, 40.7 years); fracture was caused by falling in 1 case, by traffic accident in 22, by falling from height in 5 with a mean time of 25 hours from injury to hospitalization (range, 9-38 hours); and 28 fractures included 12 Pauwels type II and 16 Pauwels type III femoral neck fracture. There was no significant difference in the baseline characteristics between 2 groups (P > 0.05).

RESULTS

The incision healing of both groups by first intention was achieved. There were significant differences in operation time, incision size, operation blood loss, the cases of blood transfusion, the amount of blood transfusion, C reaction protein level on the 2nd postoperative day, and hospitalization days between 2 groups (P < 0.05). In DHS group, anatomic reduction was observed in 20 cases (86.96%) and satisfactory reduction in 3 cases (13.04%), while in cannulated screw group, anatomic reduction was observed in 25 cases (89.29%) and satisfactory reduction in 3 cases (10.71%); there was no significant difference (chi2 = 0.660, P = 1.000). The patients were followed up 12-30 months with an average of 14.8 months. There was no significant difference (P > 0.05) in the rate of nonunion (10.71% vs. 0), the implant failure (3.57% vs. 0), and avascular necrosis of the femoral head (10.71% vs. 0) between the DHS group and the cannulated screw group. The union time was (94.5 +/- 2.0) days in the DHS group and (106.0 +/- 33.5) days in the cannulated screw group, showing no significant difference (t = -1.641, P = 0.107). The re-operation rates and the overall success rates were 25% and 75% in the cannulated group and were 0 and 100% in the DHS group, showing significant differences (chi2 = 6.650, P = 0.012). At last follow-up, there was no significant difference in Harris hip score and visual analogue scale (VAS) score between DHS group and cannulated screw group (P > 0.05).

CONCLUSION

The optimal treatment of young adults Pauwels type II or III femoral neck fracture is DHS combined with anti-rotation screw with an high overall success and less complications.