When a conservative management of gonarthrosis yields unsatisfactory results, a total knee arthroplasty (TKA) is recommended as an alternative approach. The implant survival is crucial for the long-term success of the procedure. However, in case of patients with retained hardware after past orthopedic procedures, providing correct alignment of the implant, which contributes to its longevity, is especially challenging. Here we present the use of an intra-operative ultrasonography for implant positioning in a 83-year-old male, undergoing TKA, without hardware removal, which was contraindicated due to his advanced age and comorbidities. Other imaging modalities taken into consideration are also described.
The right knee joint was approached with anterior incision. A femoral guide was introduced extramedullary. Ultrasonography was used to pinpoint the center of the femur's head. Tibial's guide was introduced intramedullary followed by a standard cut of the proximal part. Cemented ZIMMER NEXGEN prosthesis was used. Layered closure was applied. The placement of implant in neutral axis was confirmed on radiographs.
Our case demonstrates that ultrasonography might be helpful during TKA-procedure for implant positioning. However, more studies are needed to evaluate accuracy and application of ultrasound in the intraoperative settings.