Kneecap (Patellofemoral Joint-PFJ) Replacement

Not infrequently, especially in women, the area of the knee between the underside of the patella (kneecap) and the front of the femur (thigh bone) wears out. The patient particularly notices a crunching sensation within the joint and problems on inclines or stairs as well as getting up out of chairs.

If this happens in isolation, then the front surface of the femur (trochlea) is resurfaced with a metal prosthesis and a polyethylene or plastic implant resurfaces the underside of the patella. The attraction here of course is that if only the patella or kneecap is worn, the patient may keep the rest of the natural knee without operation whilst a much reduced procedure is performed to resurface the patellofemoral joint.

This procedure is much smaller than a total knee replacement and patients achieve a faster recovery.

If wear and tear subsequently occurs in the main part of the knee joint, it is possible to resurface that area around the patellofemoral replacement without resorting to a total knee joint replacement.

Compared to total knee arthroplasty:

PFJ is associated with shorter postoperative rehabilitation.
PFJ is associated with better knee kinematics in the sagittal plane because of the preservation of the tibiofemoral articulation, menisci, ACL and other supporting ligaments.
PFJ patients showed better functionality, less blood loss and greater return to activity.