Total knee arthroplasty in Japanese patients aged 80 years or older

OBJECTIVE: The population of Japan is aging rapidly, and, since the aging of patients who undergo total knee arthroplasty (TKA) is also expected, it is necessary to determine the efficacy and safety of TKA among old adult patients. METHODS: This study retrospectively analyzed the cases of patients who underwent a primary TKA for osteoarthritis at Bange Kosei General Hospital between January 2009 and June 2014 and were postoperatively followed-up for ≥1 year. Among the 2,945 knees of the 1,968 patients, 1,003 knees of 679 patients aged ≥80 years at the time of surgery were designated as the older group, and we compared their cases with those of the younger group of 1,044 knees of 673 patients aged <75 years. RESULTS: The rates of improvement of the Japanese Orthopaedic Association (JOA) score were not significantly different between the older and younger groups. Postoperative ranges of motion were significantly improved in both groups. The number of postoperative days of hospital stay in the older group was 2 days longer than that of the younger group. Concerning postoperative complications, confusion, delayed wound healing, and acute heart failure were significantly more frequent in the older group. The frequencies of pneumonia, cerebral infarction, peroneal nerve palsy, and bedsore did not differ significantly. Loosening of implants was observed: older group, n=0 joints; younger group, n=5 joints. The number of prosthetic joint infections: older group, n=5; younger group, n=2 (non-significant). CONCLUSION: The rate of improvement in the JOA score did not differ significantly between the groups. TKA is an effective and safe treatment for osteoarthritis, even in old adult patients, when the surgical indication is based on careful preoperative screening and attention to specific postoperative complications.