The use of structural allograft in primary and revision knee arthroplasty with bone loss

Abstract

Bone loss around the knee in the setting of total knee arthroplasty remains a difficult and challenging problem for orthopaedic surgeons. There are a number of options for dealing with smaller and contained bone loss; however, massive segmental bone loss has fewer options. Small, contained defects can be treated with cement, morselized autograft/allograft or metal augments. Segmental bone loss cannot be dealt with through simple addition of cement, morselized autograft/allograft, or metal augments. For younger or higher demand patients, the use of allograft is a good option as it provides a durable construct with high rates of union while restoring bone stock for future revisions. Older patients, or those who are low demand, may be better candidates for a tumour prosthesis, which provides immediate ability to weight bear and mobilize.

Figure 1

AP radiograph showing a knee with severe polyethylene wear and evidence of major bone loss (a). A CT scan showing massive bone loss of the medial and lateral femoral condyles due to osteolysis (b). (reprinted from Backstein et al. [2]).

Figure 2

A radiograph shows uncontained bone loss in the medial femoral condyle secondary to osteolysis (a). A radiograph showing revision TKA with reconstruction of the medial femoral condyle using structural allograft fixed with screws (b).

Figure 3

Intraoperative pictures of allograft-prosthesis composite (APC), AP view (a) and lateral view (b).

Figure 4

Radiograph showing a supracondylar periprosthetic fracture with major bone loss ((a) and (b)). An AP radiograph showing a revision with femoral allograft-implant composite (c).