[Total knee arthroplasty: a 4.5-year follow-up]

To present the short- and mid-term follow-up results of primary total knee arthroplasty.

We performed a total of 97 cemented total knee replacements (47 right, 50 left) with posterior cruciate ligament retention in 66 patients (60 women, 6 men). The mean age at the time of surgery was 65.2 years (range 29 to 82 years). Preoperative diagnoses were primary osteoarthrosis (n=60), rheumatoid arthritis (n=3), systemic lupus erythematosus (n=2), and post-traumatic osteoarthritis (n=1). Thirty-one patients had bilateral knee replacements, of which 29 were performed at the same session. Pre- and postoperative clinical evaluations were made according to the clinical rating system of the Knee Society. Radiographic evaluations were made according to the Fairbank's criteria preoperatively, and to the total knee arthroplasty radiographic evaluation and scoring system of the Knee Society postoperatively. The mean follow-up was 4.5 years (range 24 to 98 months).

Clinical results were good or excellent in 94.8 percent of patients. Complications encountered were deep infection in two patients, patellar dislocation in two patients, deep venous thrombosis in two patients, and patellar tendon rupture in one patient. The mean increases in knee and functional scores were 42.94 and 39.87, respectively. Improvement in the mean postoperative knee flexion was 35.72 degrees. The mean leg alignment was 6.3 degrees valgus. No components required revision because of aseptic loosening.

Posterior cruciate ligament retaining implants were found to yield successful clinical and radiologic results during short- and mid-term follow-up period.