Abstract
Purpose
Failure resulting from a recurrent infection in total knee arthroplasty (TKA) is a challenging problem. Knee arthrodesis is one treatment option, however fusion is not always successful, as there is huge bone defect. The authors reports a new arthrodesis technique that uses a bundle of flexible intramedullary rods and an antibiotic-loaded cement spacer.
Methods
There were 13 cases of arthrodesis due to recurrent periprosthetic joint infection, which were performed by the first author (WS Cho) at Asan Medical Center in Seoul from 2005 to 2014. All previous prosthetic components were removed and cement was thoroughly excised using a small osteotome. Two stage operation was done in most of cases. After thorough debridement, antibiotics loaded cement was inserted in first stage, flexible intramedullary rods were inserted retrogradely in the femoral side with the knee in flexion under fluoroscopy guidance. After filling the femoral intramedullary canal, the rods were then driven back securely into the tibial medullary canal. We aimed for as much rod length as possible to maximize stability. After 6 weeks of first stage operation, the rods of the femoral and tibial sides were arranged such that they overlapped and interdigitated to maximize mechanical strength, maintain the limb length and keep the rotational alignment. The interdigitating rod ends were tightly fixed using two (or three) cerclage wires. Antibiotic-loaded cement was filled into the knee joint space so that the cement is fit to the irregular contour of the femur and tibia, which was resulted from the severe bone loss. Postoperatively, patients were allowed to weight bear as tolerated.
Results
The procedure was successful in every cases with no evidence of rod or cement failure at least 1 year follow up. Also there was no recurrence of infection.
Conclusion
Although this simple method was not for bony union, the authors could achieve stable knee joint without recurrence of infection.
