Unfortunately knee arthroplasty components do not last as long as hip replacement components and the need for revision joint replacement is becoming increasingly common. Like total hip replacements, the failure of the implant often occurs gradually over time, so all patients with joint replacements should have a check-up x-ray every year. Knee revisions are difficult and fairly involved procedures in which the original components are removed and the knee is reconstructed with new components. The most difficult part of the procedure is re-establishing the original level of the joint line and balancing the ligaments around the knee which are often somewhat compromised from the failing prosthesis. The risk of complications in patients with BMI (body mass index) over 30 is significantly increased and approaches 50% in patients with BMI over 40. We generally do not offer this procedure in patients with BMI 40 or over.
The surgical time is extensive and most patients require a transfusion after surgery. Cadaveric bone graft may be necessary if there is a large amount of bone loss. Most patients will spend 3-5 days in the hospital and begin physical therapy within 24 hours after surgery. Most patients will receive low-molecular weight heparin for 3 weeks after surgery to reduce the risks of blood clots. Depending on the extent of the revision, weight bearing may be limited initially to allow for bony ingrowth. Total recovery often takes 3-6 months depending on the type of revision surgery.