Purpose: To examine the outcome of primary and revision knee arthroplasty in very elderly patients.

Methods and Results: Patients in their 90th year of life who underwent primary or revision knee arthroplasty between January 2000 and September 2007 were identified. Data was collected regarding demographics, ASA grade, co-morbid factors, complications, length of inpatient stay, the need for transfusion and discharge destination. Thirty day, 1 year and current mortality figures were calculated.

Twenty one procedures were performed on 18 patients with a mean follow up of 18.8 months (3–57.9). There were 14 primary total knee replacements and 7 revision procedures. The mean age at the time of surgery was 90 years and 10 months (89 years 1 month to 94 years 4 months). The majority of patients were female (15). All patients were ASA grade 2 or 3. The average orthopaedic inpatient stay was 17 days. Thirty percent of patients required a period of further inpatient rehabilitation or convalescence after discharge from our institution. Nine patients experienced a post-operative complication. Mortality at 30 days was 0%, at 1 year 6% (1/16), and is currently 17% (3/18).

Conclusion: Very elderly patients are able to tolerate primary and revision knee arthroplasty although there is a high rate of peri-operative complications. We propose that there should be a different tariff for arthroplasty procedures in extremely elderly patients to reflect the increased rate of complications and prolonged postoperative hospital stay.