The purpose of this study is to compare the treatment results of fracture fixations by using two minimal invasive techniques for patients with periprosthetic femoral fractures following total knee arthroplasty.

We reviewed 36 patients (5 males, 31 females) of periprosthetic femoral fractures whom were treated surgically between January 2005 and January 2011. Mean patient age was 68.9 years (range, 43 to 81 years) old and the follow-up period averaged 41 months (range, 18 to 72 months). Nineteen patients were treated with minimal invasive locking plate fixations (group I) and 17 patients with retrograde intramedullary nailing (group II). Clinical and radiological outcomes in each group were comparatively analyzed.

Successful bone unions occurred in all patients and the mean time to bone union was 3.7 months in group I and 4.2 months in group II. There were no statistical differences between the two groups according to mean operative time and mean intraoperative blood loss. There were also no statistical differences between two groups according to clinical outcomes but the valgus deformity was apparent in group II and radiological outcomes revealed significant differences between the two groups.

For the treatment of periprosthetic femoral fractures after total knee arthroplasty, two minimal invasive techniques have shown good clinical results. However, the minimal invasive plate fixation showed better results in the radiological alignments.