What is Partial Medial Knee Replacement?
Partial medial knee replacement is a surgery to replace only the medial part of your damaged knee. It is also called unicompartmental knee replacement.
The knee is one of the largest and most complex joints in your body. The joint is connected to your thigh bones and bones of the lower leg by various ligaments.
The knee joint is made of three compartments, the lateral, medial and patellofemoral compartments. The inside part of your knee is the medial compartment of the knee. This typically is the most common region of the knee to have arthritic damage for most people.
Indications for Partial Medial Knee Replacement
Aging and joint conditions such as osteoarthritis cause breakdown of the cartilage of your inner knee leading to pain and inflammation which may not respond to pain medications or non-surgical treatment and may need surgery. Damage to the medial side of your knee may also cause knee stiffness. This procedure is a potential option for those select patients without any symptoms or arthritic wear/damage to the other compartments of the knee.
Your doctor physically examines your knee by performing specific movements. The exact location and severity of the pain are essential to identify the type and extent of damage occurred. Your doctor will take your medical history and may order an X-ray, CT-scan or MRI to finalize the diagnosis.
Partial Medial Knee Replacement Procedure
- The surgery is performed under spinal or general anesthesia. Dr. Eccles will make an incision in the skin over the affected knee to expose the medial aspect of the knee joint. Then, the damaged portions of the tibia (shin) bone are cut at appropriate angles using specialized jigs, computer navigation, or with the help of a robot. The femoral bone is then also cut to remove the damaged arthritic areas and be prepared to receive the prosthetic components.
- The metal component trials are placed and the knee is tested for good motion and balance. When satisfactory, the real components are opened and are cemented onto the bone ends.
- Dr. Eccles will place a plastic piece between the implants to provide a smooth gliding surface for movement. This plastic insert will support the body’s weight and allow the femur to move over the tibia like your native knee articulates but without the arthritic pain.
- With all the new components in place, the knee joint is tested through its range of motion again. The entire joint is then irrigated and cleaned with a sterile solution. The incision is carefully closed and a sterile dressing is placed over the incision.
Rehabilitation begins immediately following the surgery. A physical therapist will teach you specific exercises to strengthen your leg, restore knee movement, and get you up to walk around. You will walk with a walker as you get used to your new knee. Your physical therapist and Dr. Eccles will also provide you with a home exercise program to strengthen your thigh and calf muscles.
Complications of the Surgery
As with any major surgery, there are risks and complications. While the majority of complications are rare, the possible risks associated with total knee replacement surgery include:
- Arthritic progression within the other compartments of the knee
- Knee stiffness
- Blood clots (deep vein thrombosis)
- Nerve and blood vessel damage
- Ligament injuries
- Patella (kneecap) dislocation
- Plastic liner wearing out
- Loosening of the implant
Advantages of the Surgery
The advantages of partial medial knee replacement surgery include:
- Smaller incision
- Minimum bone removal
- Shorter recovery period
- Potentially a more natural feeling knee