Metaphyseal bone loss in revision knee arthroplasty

Abstract

The etiology of bone loss encountered during revision total knee arthroplasty (TKA) is often multifactorial and can include stress shielding, osteolysis, osteonecrosis, infection, mechanical loss due to a grossly loose implant, and iatrogenic loss at the time of implant resection. Selection of the reconstructive technique(s) to manage bone deficiency is determined by the location and magnitude of bone loss, ligament integrity, surgeon experience, and patient factors including the potential for additional revision, functional demand, and comorbidities. Smaller, contained defects are reliably managed with bone graft, cement augmented with screw fixation, or modular augments. Large metaphyseal defects require more extensive reconstruction such as impaction bone grafting with or without mesh augmentation, prosthetic augmentation, use of bulk structural allografts, or use of metaphyseal cones or sleeves. While each technique has advantages and disadvantages, the most optimal method for reconstruction of large metaphyseal bone defects during revision TKA is not clearly established.

Keywords: Augments; Bone loss; Bulk structural allograft; Metaphyseal cone; Metaphyseal sleeve; Revision total knee arthroplasty.

Fig. 1

Management of bone loss during total knee arthroplasty revision for mechanical failure. a shows preoperative anteroposterior (left) and lateral (right) radiographs. b shows postoperative anteroposterior (left) and lateral (right) radiographs following reconstruction with a constrained condylar knee (CCK) design, two 5-mm posterior femoral augments, a 5-mm medial distal femoral augment, a 10-mm lateral distal femoral augment, a trabecular metal tibial metaphyseal cone, and diaphyseal-engaging stems