Periprosthetic distal femoral fractures after total knee replacement treated by ORIF. Mid to long-term follow-up study in 12 patients.

Abstract

Periprosthetic fractures following total knee arthroplasty are a quite uncommon traumatic lesion that often are present in elderly patients with osteoporosis and comorbidities. The most common periprosthetic fracture affects the distal femur. The main internal fixation techniques are ORIF with a locking plate and retrograde intramedullary nailing. In the present study, we report the medium-long term results in 12 patients with a distal femoral periprosthetic fracture stabilized with a locking plate. We reviewed 12 patients affected by a periprosthetic distal femur fracture surgically treated between 2010 and 2016 by ORIF using a locking compression plate after an average follow-up of 5.75 years. The average age of the patients at diagnosis was 78 years. The mean interval time between knee arthroplasty and distal femoral fracture was 8.25 years. Clinical results were assessed using the WOMAC score, while radiographic results according to Beals and Tower's criteria. All fractures of our series were type II according to the Rorabeck and Taylor classification. At follow-up, the WOMAC score ranged from 40.5 to 76.5 points (average 53.92). Radiographic results, according to Beals and Tower's criteria, were excellent in 5 patients and good in 7. All patients returned to their previous daily activities. We believe that reduction and internal fixation with a locking plate is a surgical option of treatment that provides satisfactory clinical and radiological results in Rorabeck type II periprosthetic distal femoral fractures.