Unicompartmental knee replacement for medial compartmental knee osteoarthritis:a four to six-year follow-up / 中国组织工程研究

ABSTRACT

BACKGROUND:Unicompartment knee replacement is more popular for smal trauma, rapid recovery, low complication and almost normal knee mechanics, and has been more and more used in clinic to repair single compartment knee disease. At present, there is no report about the influence of the angle of the single condyle prosthesis on the survival rate. OBJECTIVE:To evaluate the effectiveness of unicompartmental knee replacement for medial compartmental osteoarthritis of the knee in 4-6 years of fol ow-up. METHODS:Thirty patients with medial compartmental osteoarthritis of the knee were treated by unicompartmental knee replacement with Oxford system. Complication occurrence was observed. Curative effects were evaluated with Hospital for Special Surgery score before and 3 months, 6 months and 1 year after surgery. On anteroposterior view, the varus/valgus alignments of the tibial components were measured relative to the long axis of the tibia. On lateral view, flexion/extension of the femoral component was measured relative to the posterior femoral cortex. RESULTS AND CONCLUSION:(1) Primary healing of incision was obtained in al patients, and no infection or lower limb deep venous thrombosis occurred. (2) Al of the patients were fol owed up for 48-72 months. There was no prosthetic loosening, dislocation or revision for contralateral compartment and patel ofemoral joint symptoms. (3) Hospital for Special Surgery score was significantly increased to (90.47±4.05) (P=0.00). (4) Tibial placement angle of single condyle prosthesisThe axis of the prosthesis was perpendicular to the axis of the tibia in 21 cases. Varus placement2° in 1 case, 4° in 3 cases, 5° in 2 cases, 6° in 2 cases, and 10° in 1 case. No valgus occurred in the tibial side. (5) Femoral prosthesis placement angleThe axis of the femoral prosthesis was paral el to the posterior edge of the femoral cortex in 22 cases, on the flexed position4° in 2 cases, 5° in 1 case, 6° in 1 case and 7° in 1 case;in the extension position3° in 1 case, 4° in 1 case and 5° in 1 case. (6) Results suggested that the unilateral condylar replacement for the repair of medial compartment osteoarthritis of the knee has a good initial effect. The middle-term and long-term efficacy needs longer fol ow-up study.