Patellofemoral replacement, also known as patellofemoral arthroplasty, is a surgical procedure that involves replacing the diseased or damaged patellofemoral joint with an artificial implant. The patellofemoral joint is the joint between the kneecap (patella) and the thigh bone (femur). This procedure is primarily performed for patients with isolated patellofemoral arthritis, where the cartilage on the undersurface of the kneecap and the corresponding groove on the femur have worn away, causing pain, instability, and functional limitations.
The patellofemoral replacement procedure is typically performed under general anesthesia. The surgeon makes an incision over the front of the knee, providing access to the patellofemoral joint. The damaged cartilage and any loose fragments are carefully removed, and the undersurface of the patella and the corresponding groove on the femur are prepared to receive the implant.
The patellofemoral implant consists of two components: a metal femoral component and a polyethylene (plastic) patellar component. The femoral component is shaped to mimic the natural groove on the femur, and the patellar component is designed to replace the worn surface of the kneecap. The components are fixed in place using bone cement or press-fit techniques.
One of the key advantages of patellofemoral replacement is that it preserves the healthy parts of the knee joint, including the cruciate ligaments and the tibiofemoral joint (the main knee joint). This allows for more natural knee function and potentially a faster recovery compared to total knee replacement (TKR). Additionally, patellofemoral replacement is associated with a smaller incision and less bone removal compared to TKR.
Following surgery, patients undergo a period of post-operative rehabilitation and physical therapy. This helps to strengthen the muscles around the knee, improve range of motion, and optimize the function of the new implant. Pain medications are prescribed to manage post-operative discomfort, and patients are advised to avoid activities that put excessive stress on the patellofemoral joint.
While patellofemoral replacement can be an effective treatment option for select patients, it is important to note that it may not be suitable for everyone. Ideal candidates for the procedure are typically younger individuals with isolated patellofemoral arthritis who have intact cruciate ligaments and relatively preserved tibiofemoral joint surfaces. Patients with advanced knee arthritis affecting the tibiofemoral joint may require a total knee replacement instead of a patellofemoral replacement.
As with any surgical procedure, there are risks associated with patellofemoral replacement. These include infection, blood clots, stiffness, patellar instability, implant wear, and persistent pain. Patients should have realistic expectations about the outcomes and limitations of the procedure and discuss these with their orthopedic surgeon.
In conclusion, patellofemoral replacement is a surgical procedure that involves replacing the damaged patellofemoral joint with an artificial implant. It is primarily performed for patients with isolated patellofemoral arthritis. The procedure preserves the healthy parts of the knee joint and may result in improved knee function and faster recovery compared to total knee replacement. However, patient selection is crucial, and the procedure may not be suitable for everyone. Patients should consult with their orthopedic surgeon to determine if patellofemoral replacement is the right treatment option for their specific condition.