Knee Replacements Last 25 Years Save

UK registry reports that greater than 80% of total knee replacements can last for 25 years.

The outcomes regarding the duration and durability of knee arthroplasties is sketchy, with many orthopedists projecting a 15 to 20 year survivial. Hence the need for an appraisal of the data.

This study was a systematic review and meta-analysis of 33 case series, with a total of 7232 knee replacements. Twenty six case series looked at total replacement, whereas seven reported survival of unicompartmental replacement. Data from the Australian and Finnish national registries were used, with a total of 299 291 total replacements and 7714 unicompartmental replacements.

The most reliable data came from the national registries showing that for total knee replacements:

• At 15 years, 93% were intact (95% confidence interval 92.8 to 93.1)
• At 20 years, 90.1% of replacements survived (89.7 to 90.4)
• At 25 years, 82.3% of replacements were still intact 

For unicompartmental knee replacements:

• At 15 years, 76.5% were still intact (75.2 to 77.7)
• At 20 years, 71.6% survived (69.6 to 73.6)
• At 25 years, 69.8% were still intact (67.6 to 72.1)

Since at least 80% of total replacements will last for 25 years, it is possible that more candidates may be offered surgery at a younger age.