A partial knee replacement is an alternative to total knee replacement for some patients with osteoarthritis of the knee. This surgery can be done when the damage is confined to a particular compartment of the knee.
In the past, partial knee replacement was reserved for older patients who were involved in few activities. Now, partial knee replacement is often preferred in the younger population as their recovery is quicker and often with much less pain. About 5% to 6% of patients with arthritic knees are estimated to be eligible for partial knee replacement.
Who is a candidate for partial knee replacement?
Patients with medial, or lateral, knee osteoarthritis can be considered for partial knee replacement. “Medial” refers to the inside compartment of the joint, which is the compartment nearest the opposite knee, while “lateral” refers to the outside compartment farthest from the opposite knee. Medial knee joint degeneration is the most common deformity of arthritis.
Other factors to consider:
- You may want to consider a knee replacement if your knee pain persists despite your taking anti-inflammatory drugs and maintaining a healthy weight.
- Your doctor will ask you to identify the area of pain in your knee, then check your range of motion and the knee’s stability. An X-ray of the knee will determine your eligibility for partial knee replacement. However, your surgeon may not know for certain if you are a good candidate until the surgery has begun.
- You must have an intact anterior cruciate ligament, a sufficient range of knee motion, damage to only one compartment, and a stable knee. The angulation of the deformity is also considered.
- In the past, a partial knee replacement was considered only in patients older than 60 years who were sedentary but younger, more active patients are increasingly being considered.
Advantages of Partial Knee Replacement
Multiple studies show that a majority of patients who are appropriate candidates for the procedure have good results with unicompartmental knee replacement.
The advantages of partial knee replacement over total knee replacement include:
- Quicker recovery
- Less pain after surgery
- Less blood loss
Also, because the bone, cartilage, and ligaments in the healthy parts of the knee are kept, many patients report that a unicompartmental knee replacement feels more natural than a total knee replacement. A unicompartmental knee may also bend better.