Impact of preoperative knee deformity on the outcome of total knee replacement using the PFC system

Backgrund. The purpose of our study was to evaluate the impact of preoperative knee deformity on TKR results and the effectiveness of unconstrained PFC systems in the correction of these deformities in knees affected by degenerative disease. Material and methods. We performed a retrospective study of 91 consecutive TKRs performed between 1995-2000 in 79 patients (71 women and 8 men, mean age 67.2 years), during which 74 PFCs and 17 PFCSs were implanted. The mean follow-up was 48.3 months (range: 13-58 years). Functional status was evaluated using the Knee Society Score (KSS), and the radiological results were assessed on the basis of standard plain x-ray pictures. Results. We found 26.7% excellent outcomes, 67.8% good, 3.3% fair and 2.2% poor. There were no statistically significant differences between the anatomical and radiological outcomes of TKR in knee joints with flexion, valgus or varus preoperative deformities. The effectiveness of the unconstrained system of total knee arthroplasty in correction of the flexion or valgus/varus knee joint deformity was very good, given proper patient selection and meticulous surgical technique. Conclusions. Clinical and radiographic studies show that preoperative knee deformation has no impact on the early results of TKR with an unconstrained PRC system. The functional and radiographic results of TKR with an unconstrained PFC system confirm the very high effectiveness of this technique in the correction of preoperative deformation of the knee with degenerative changes. The results of TKR with un-constrained PFC systems in short-term follow-up (1-5 years) are very good.