Hybrid External Fixation as a New Treatment Method for Periprosthetic Femoral Fracture: A Case Report

Abstract

D isplaced periprosthetic fractures of the distal part of the femur proximal to a stable total knee replacement are infrequent and present a challenging surgical problem1. The reported prevalence is 0.3% to 2.5%, but it is expected to increase because of the increased numbers of total knee replacements being performed and the increasing longevity of patients2-5. Fig. 1-A and 1-B Initial anteroposterior (Fig. 1-A) and lateral (Fig. 1-B) radiographs showing a Lewis and Rorabeck type-II periprosthetic supracondylar femoral fracture3 in an eighty-three-year-old man with osteopenia and a stable implant. Treatment options include bed rest; traction and cast immobilization; operative fixation with Rush rods, supracondylar nails, and plates with or without bone-grafting; and revision arthroplasty with a long-stem prosthesis1,2,4,6-10. Each of these options is associated with substantial complications2,5,7. We have used external fixation systems to treat fractures in appropriately selected elderly patients11. External fixation offers secure fracture fixation and permits early mobilization of the patient. A hybrid external fixation frame stabilizes and realigns a fracture by combining (1) a distal circular fixation element to which tension wires, inserted through metaphyseal cancellous osteoporotic bone, are secured and (2) a proximal monolateral fixation element to which half-pins are secured for fixation to the diaphyseal bone. To the best of our knowledge, the use of such a frame has not been previously reported in the English-language literature. Our patient was informed that data concerning the case would be submitted for publication. Fig. 2-A and 2-B Postoperative anteroposterior (Fig. 2-A) and lateral (Fig. 2-B) radiographs, made after the placement of a hybrid external fixator, demonstrating satisfactory coronal and sagittal alignment and no shortening. a = 2/3 ring, b = reduction unit, c = tensioned wires, d = half-pins, …