ABSTRACT
Despite the many benefits of total knee arthroplasty (TKA) in the treatment of degenerative arthritis, infection of the total knee prosthesis presents a dangerous post-operative complication affecting 0.5-1.9% of all cases. Infection after the first three post-operative weeks is treated with either one or two-stage revision operations involving the removal of all prosthetic components. Two-stage revision operations are more commonly used and involve the removal of prosthetic components followed by the implantation of a cement mold infused with antibiotics (antibiotic spacer) as well as systemic antibiotic treatment for four to six weeks before prosthetic reimplantation. This case report details a TKA revision in a patient with osteoarthritis of the knee. The patient presented with an elevated erythrocyte sedimentation rate, C-reactive protein, and white blood cell count nearly two years after the primary operation and was found to have an infected total knee prosthetic. A two-stage revision was planned but due to scheduling disruption by the coronavirus disease 2019 pandemic, the second stage of the operation was delayed until 12 months after the stage one operation. The patient ambulated without pain on an antibiotic spacer for 12 months, providing information about the long-term use of spacers. This case also offers a look at a potential benefit to one-stage operations, which have been shown in the literature to have similar outcomes as two-stage operations. The patient had a medical history of psoriasis and immunosuppressive treatment with methotrexate, two risk factors for prosthetic joint infection, and may have benefited from prophylactic antibiotic therapy extending beyond the perioperative period. The goal of this case report is to detail the prolonged use of an antibiotic spacer, examine the risks and benefits of one and two-stage total knee revisions, and discuss prophylactic antibiotic use in high-risk patients following TKA.
ABSTRACT
Total knee arthroplasty (TKA) systems are designed to maximize the longevity of the implant. However, an unusually high rate of aseptic tibial tray loosening was observed in the DePuy ATTUNE® total knee arthroplasty system (DePuy Synthes, Warsaw, USA). Affected patients noted symptoms of instability and reproducible pain at the bone-implant interface. However, there was no radiographic evidence of lucency or implant failure. Intra-operatively, the tibial component was grossly loose and lacked adhered cement. We hypothesize that the loosening is due to the smooth architecture of the undersurface of the tibial component, lacking either grit blasting or porous coating.
