Treatment of Endoprosthetic Knee Joint Infection in the Setting of Massive Bone Loss With Fusion of Femoral and Tibial Antibiotic Rods

Abstract

Chronic periprosthetic joint infection of the knee often requires staged surgical treatment combined with several weeks of intravenous antibiotic treatment. The first stage involves resection arthroplasty and placement of an antibiotic-cement spacer. A massive bone defect results from removal of a tumor-style prosthesis, introducing challenges to spacer creation and placement. This article describes a 27-year-old man who was treated 12 years prior for stage IIB osteosarcoma of the right proximal tibia with wide resection and alloprosthetic composite reconstruction. He developed chronic periprosthetic infection of the construct. Three surgical washouts and intravenous antibiotics failed to eradicate the infection, therefore 2-stage exchange arthroplasty was initiated. The first stage involved resection of all implants and allograft, and placement of a novel antibiotic-impregnated spacer. The spacer was created by locking a retrograde femoral nail and an antegrade tibial nail together at the knee joint level. This construct was then encased in antibiotic-impregnated cement to achieve fill of the massive tibial defect. After 6 weeks of intravenous antibiotic infusion, the infection was successfully eradicated and he was indicated for reimplantation arthroplasty with custom hinged knee components. Utilization of interlocked femoral and tibial nails in this manner has not been described for creating an antibiotic-laden temporary knee arthrodesis spacer as the first stage in treatment of periprosthetic joint infection. This strategy achieves stable knee fusion although avoiding violation of the hip and the complications of external fixation. Application of this technique may be particularly beneficial in the setting of massive bone loss.