Anatomic and functional reconstruction of the joint in severe bone and ligamentous knee instability with semi-constrained systems of total knee replacement.

Background. The study was made to evaluate efficiency of semi-constrained systems of TKR in correction of severe bone and ligamentous instability in knee joint with degenerative disease. Material and methods. Retrospective investigation of the 50 consecutive TKRs performed in 40 patients (40 women) between 1995-2000 was made. There were following prosthesis implanted: GSB - 45 and Endo-Model - 5. 48 knees were evaluated. Patients' mean age was 65,6 years old. Mean time of follow-up was 32,8 months (range: 1-5 years). Functional status was evaluated according to KSS scale and radiographic results were investigated with standard plain x-ray pictures. Anatomic results were investigated by the computed posturography with the use of Metrecom Systems. Results. In study group there were: 26% excellent, 68% good, 4% fair and 2% poor results respectively in Knee Score (KSS). There are no statistical differences between anatomical and radiological results of TKR in the knee joints with severe deformity. A little poorer efficiency of the semi-constrained system of total knee arthroplasty in functional reconstruction of the knee joint was due to poor general-health status of the patients and multi-joint nature of their disease. Conclusions. 1. Results of TKR with semi-constrained systems in short-term follow-up (1-5 years) are very good. 2. Posturographic and radiographic studies show that with semi-constrained system of TKR allows for reconstruction of proper anatomy of the knee joint even in severe deformed cases. 3. Functional results of TKR with semi-constrained systems are good in severely unstable and deformed knee joints.