This depends on age , weight and activity. In most older patients (greater than 65) a TKR will last 10-15 years. Partial knee replacements last approximately 8-10 years. However , UKRs are much less invasive. Less bone is removed , no ligaments are removed and the knee has a more stable and normal feeling than a TKR. I would recommend a UKR over a TKR whenever this is possible (only 10% of the time) , especially in a younger person.