Patellofemoral Partial Knee Replacement
Patellofemoral knee replacement is a procedure that resurfaces the damaged kneecap and the corresponding area on the femur bone to allow for improved alignment and pain relief.
Who is a Candidate?
- Anterior osteoarthritis.
- A damaged patella, but still have great function in the rest of their knee.
- Joint deterioration that limits them from their daily activities.
Good candidate for partial knee replacement over a total knee replacement if:
- The patient has anterior and medial knee pain.
- The patient has an almost normal range of motion in their knee (90 degrees).
- The patient's knee is stable.
Benefits of this Procedure
The benefits of this procedure compared to a total knee replacement are:
- Preservation of bone
- Decreased blood loss
- Decreased post-operative pain
- Shorter hospital stay
- Faster rehab/recovery time
- Retain a better range of motion in the knee
- More normal knee kinematics
- Smaller implant
What is a Patellofemoral Partial Knee Replacement?
Due to wear and tear, the kneecap (patellofemoral joint) may be worn out and will need to be replaced. The degree of arthritis or damage in the kneecap will be determined by the surgeon. If other parts of the knee besides the kneecap are damaged and need to be repaired, then this procedure will not fit the patient and a more suitable procedure will be recommended.
Anterior knee pain in the joint is felt between the kneecap and the thighbone. This area is where the patellofemoral partial knee replacement procedure is performed. By resurfacing the trochlea (end of the thighbone), the pain will then be reduced.
To perform the procedure, an incision is made in the front of the knee. The worn-out kneecap is resurfaced and cartilage is removed from the bone in the area under the femoral implant. The implant located between the kneecap and the thighbone is then positioned into place.
The implant is designed to provide the patient with the joint's natural kinematics of the kneecap. The movement and motion of the patella and thighbone should feel less painful, and have a smoother more natural motion. The shape and motion of the knee will be different than with the natural knee, so the muscles and ligaments will need to adapt. At first, this may lead discomfort and fatigue for the patient.
A patellofemoral knee replacement usually lasts 10 to 15 years.
The Allergic Alternative
If a patient is allergic to any type of metal that the implant is made of, then the surgeon will change the type of metal to make it possible for the patient to have the procedure.
If the patient has reoccurring pain, then painkillers will be prescribed as necessary. Physical therapy will work the patient to get their knee bending again. Only days after surgery, a physical therapist will work with the patient to get their knee bending again. A list of exercises will be given to the patient from the physical therapist. Most patients will return to work and other daily activities within 4 to 8 weeks post operation.
The patient should avoid the following things to have their implant last longer:
- Stressful physical activities
- All contact and impact sports
- Heavy lifting (more than 40 pounds)
- Jumping from a long distance or from heights