gms | German Medical Science

Objectives: The elderly patients are more prone to surgical risks regardless of the procedure itself. Overall mortality rate is also expected to be high in this population. The aim of this study is to evaluate the survival rates of octogenarians who had undergone knee arthroplasty procedures.

Methods: This is a retrospective study. In our clinic between November 1996 and May 2014, 62 knee arthroplasties were performed to 52 patients who were older than 80 years at the time of operation. Of these 62 procedures, five were revision and the remainders were primary total knee arthroplasties. None of the primary prosthesis in this study was revised. Ten patients had bilateral knee arthroplasty; whereas only one of them underwent a simultaneous operation. In our clinical database, the preoperative American Society of Anesthesiologists (ASA) grades were available for 45 procedures. The database of Civil Registry Service was used to assess if the patients were alive at the time of the study; and if they were dead, their dates of death were recorded. The ages of the patients at the time of the operation, the time span between their operation and either their death or today were calculated. The five, 10, and 15 - year survival rates of patients were determined. Descriptive statistics, t-test, Kaplan-Meier survival analysis and survival analysis using life tables were done utilizing SPSS v18 program.

Results: The ASA grades of eight patients were one, 36 were two, and one was three. At the time of study 30 patients (57.69%) were alive and 22 of them (42.31%) were dead. Four out of 10 of the bilateral cases were dead. Based on 62 procedures, the mean age of the patients at the time of the operation was 82.56 ± 2.18 years (range, 80 - 89). The mean age of the patients at the time of their deaths was 88.63 ± 3.95 years (range, 82 - 99). For the patients who had passed away, the mean time span between the operation and their death was 6.4 ± 4.66 years (range, one month - 17.50 years). The mean age of the patients alive at the time of study were 86.63 ± 3.60 years (range, 82 - 96). The mean time passed since their operation (based on 35 procedures) was 4.41 ± 2.9 years (range, three months - 13.10 years) for the patients still alive. The mean age of the patients at the time of operation was not significantly different between the dead and alive ones (t-test, p=0.749). Only one patient died in the first ninety days postoperatively. One year mortality rate was 4.84% (three patients). Kaplan-Meier survival analysis revealed that mean survival time of the patients was 6.4 years (95% confidence interval [CI], 4.644 lower bound - 8.156 upper bound); median survival time was 5.6 years (95% CI, 4.243 lower bound - 6.957 upper bound). Five year survival rate was 59%, 10-year was 19%, and 15-year was 7%.

Conclusion: Octogenarians benefit from knee prosthesis longer than our expectations. With proper patient selection, early mortality risks can be avoided.