On occasion, a knee replacement procedure is considered “failed” and needs to be re-operated to improve the result. There are multiple reasons for failure which include infection, wearing out of the plastic bearing surface, loosening of the implant from the bone, instability, tendon tears, allergic reactions, alignment issues, and other less common reasons.
Revision knee replacement surgery is a more significant procedure than a first time (primary) replacement. The procedure involves removing the replacement part(s) from the bones, and placing a new implant. Removal may involve extra bone removal and/or soft tissue exposure. The new replacement requires longer parts to provide more stability to the bone. The postoperative recovery may be longer than the first replacement, and the amount of knee motion may be less. However, revision procedures are necessary if the initial knee replacement result is unsatisfactory.