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Treatment of subtrochanteric nonunion of the femur: whether to leave or to exchange the previous hardware.

OBJECTIVE
Our aim was to compare the clinical results of two different methods for treatment of subtrochanteric nonunion: an additional fixation to the previous hardware, and exchange of previous hardware.


METHODS
We retrospectively analyzed 19 cases of subtrochanteric nonunion, and compared clinical results from 10 cases (Group 1) with exchange of the previous hardware, and 9 cases (Group 2) with retained previous hardware and an additional fixation. Autogenous bone grafting were performed for all cases. The mean age of the patients was 49.1 years in Group 1, and 48.2 years in Group 2. The mean follow-up period was 19.3 months.


RESULTS
The union rate was 100% in Group 1, and 77.8% in Group 2 (p<0.05). The average time of union was 7.6 months in Group 1, and 6.9 months in Group 2. The mean preoperative leg length discrepancy (LLD) was 8.3 mm in Group 1, 10.0 mm in Group 2; and the mean final LLD was 13.9 mm in Group 1, and 11.2 mm in Group 2. The mean length of hospital stay was 23.8±3.3 days in Group 1, and 18.2±2.7 days in Group 2; the mean amount of blood transfusion was 960 ml in Group 1, and 647 ml in Group 2; and the mean operative time was 3.7±0.8 hrs in Group 1, and 2.7±0.6 hrs in Group 2 (p<0.05).


CONCLUSION
The union rate in patients with exchange of the previous hardware was better than in those with retained hardware in the treatment of subtrochanteric nonunion by complete removal of the interposed fibrous tissue and meticulous bone grafting leading to a biological environment to achieve bony union.