To evaluate the middle-term results of posterior stabilized knee arthroplasty (PSKA).
From July 1995 to July 2000, 19 knees of 18 patients were replaced with posterior stabilized prosthesis (Insall-Burstein II). Among the patients, 2 were male, and 16 female. Their average age was 62.5 years (44-78 years). One patient was operated on bilaterally. Preoperative diagnosis revealed osteoarthritis in 16 knees, and rheumatoid arthritis in 3 knees. Four knees demonstrated severe bone deficiency during surgery. Before operation, 15 of the rest knees were varusly deformed, 4 were valgusly deformed, and 8 had flexion contracture. Two patients underwent surgery previously. 17 patients (18 knees) were followed-up for 41-60 months, each of them was evaluated with the Special Surgery Knee Scoring System.
Average preoperative scores increased from 62 preoperatively to 89 postoperatively. The range of motion was significantly improved from 91 degrees preoperatively to 115 degrees postoperatively. Eleven knees were rated as excellent, 5 good, 1 fair, and 1 poor. The excellent and good rate was 88.9%.
With its design features, PSKA can effectively improve the range of motion and maximum flexion angle without compromising posterior stability. PSKA is suitable for both primary and revision total knee arthroplasty but caution should be taken for patellar complications.