Partial Medial Knee Replacement: Everything You Need to Know

Partial medial knee replacement is a surgical option for people whose knee arthritis is only on the inside (medial) part of the knee. Unlike total knee replacement, this procedure replaces just that one damaged area with metal and plastic parts, while preserving the healthy parts of your knee including bone, cartilage, and ligaments.

Who Might Benefit?

You might be a good candidate if:

• Your arthritis is confined to only the inner compartment of your knee.
• Your ligaments are intact and your knee isn’t severely stiff or deformed.
• You don’t have inflammatory arthritis or widespread damage in other parts of your knee.
• Many experts agree that proper patient selection is essential to a good outcome.

What Happens During Surgery?

The surgeon makes a smaller incision, often about 3 inches long, and checks to ensure that only one part of your knee is affected. They then remove the damaged bone and cartilage from that area and implant metal pieces on the thigh and shin bones, with a plastic spacer between them. These parts are usually cemented in place. If the knee is found to be unsuitable during surgery, it can be converted to a full knee replacement.

Benefits Over Total Knee Replacement

Because the rest of your knee remains intact, this surgery typically:

• Leads to faster recovery and shorter hospital stays.
• Causes less pain and blood loss during and after surgery.
• Lowers the risk of infection and blood clots.
• Feels more natural and may allow better knee motion after recovery.

What to Expect After Surgery

You’ll likely be up and walking with help very soon—sometimes the same day. Recovery is usually quicker than after total knee replacement, with many people returning to most activities in about six weeks. Physical therapy plays a key role in improving strength and range of motion.

Your new partial knee implant can last many years—studies show high success rates out to 10–15 years or more. However, there’s always a chance that arthritis could develop in other parts of your knee later, potentially requiring a full replacement in the future.

Things to Consider

As with any surgery, there are risks: possible blood clots, infection, nerve or blood vessel injury, stiffness, or implant issues over time. Experienced surgeons and careful planning help minimize these risks.

Partial medial knee replacement offers a less invasive, faster-recovering alternative to full knee replacement—perfect for people whose arthritis is limited to the inner side of the knee. It preserves healthy parts of the joint, provides relief from pain, and feels more natural in many cases. Always talk with a trusted orthopedic surgeon to determine the best treatment for your unique situation.