Posterior stabilized knee prosthesis for total knee replacement in patients with prior patellectomy

Objective

To determine the outcome of total knee replacement using a posterior cruciate-substituting knee prosthesis in patients who have undergone previous patellectomy.

Design

A cohort study, with a follow-up ranging from 2 to 9 years.

Setting

A university-affiliated institution specializing in elective orthopedic surgery.

Participants

Sixteen patients with arthritis of the knee who had had patellectomy. All agreed preoperatively to a prolonged postoperative follow-up.

Intervention

A cemented posterior cruciate-substituting knee replacement.

Main Outcome Measures

Stair climbing ability, the Hospital for Special Surgery knee rating system for clinical results and a radiologic rating using a zonal system.

Results

Clinical rating was 69% good or excellent. Eighty-one percent of patients could use the replaced knee as the lead leg on stair climbing. Minor radiolucency, mostly single zone only, was found. Two patients required revision because of pain, but no obvious reasons for this pain were found at operation.

Conclusion

In the absence of a patella, a posterior cruciate-substituting prosthesis gives reasonable results.