Total knee surgery: Our experience licensing

Abstract

Introduction: Revision knee arthroplasty is not a routine procedure and almost always it is a technically demanding operation. The paradigm in revision total knee arthroplasty is to achieve correct alignment of the components, maintenance of the joint space and ligament balance by providing a stable bone -implant fusion. Metaphyseal bone loss is a crucial problem in revision total knee arthroplasty. The bone loss is due to primary arthroplasty technical errors and design, or problematic removal of the implants.Aim: The aim of this article is to present our experience on total knee revision surgery using tantalum metal cones as a structural bone graft substitute in total arthroplasty failure with gross metaphyseal bone loss categorized by the AORI classification, performed by a specific surgical technique and evaluated by the Knee Society Score (KSS). Material and methods:From 2013 to 2016 at the University Clinic for Orthopedic Surgery in Skopje 21 patient has been treated with revision total knee arthroplasty. Twelve patients had type 1/type 2 bone defects according to AORI, and nine had type 3 bone defect. We used trabecular metal bone graft in type 3 bone defects. A special emphasis is placed on preoperative planning according to the classification system for ligament and soft tissue damage as well as the AORI classification in order to determine the quantity, location and extent of the bone loss. In our series in patients with type 3 deformities, trabecular metal augments were used. This material resembles the human trabecular bone by its cellular structure and elastic characteristics.Results: Preoperatively, all the patients had Knee Society Score below 60, most of them were housebound, experiencing great pain and disability. After six months 95% were rated excellent, and on one year follow up, 89% were rated good or excellent (KSS score above 82, mean score 81.5), 1 patient was marked as poor with a complication -dislocation of the prosthesis. In the follow up period there was no infection. Conclusion:Our results of revision knee arthroplasty by using the trabecular metal augments with at least a year of follow up are excellent according to the KSS compared to the other studies. The disadvantages of the study are mentioned and the need for further investigation is stressed.