People with osteoarthritis who need a knee replacement may do just as well—or even better—with a partial replacement rather than a total replacement, according to a 2019 study in The Lancet.
In a large randomized clinical trial, U.K researchers compared outcomes of 538 patients (average age 65) who underwent knee replacements for osteoarthritis of the knee’s medial compartment—one of three compartments that make up the knee and typically the compartment most severely affected in osteoarthritis.
Half of the patients had a partial knee replacement, which involved replacing only the affected compartment. The other half had a total knee replacement in which the damaged compartment as well as the other two compartments were replaced. The researchers observed patients for five years after their procedures. They found that partial replacement had a slight edge over total replacement when it came to overall lower healthcare costs; less pain; fewer complications, such as knee pain and stiffness; and faster recovery.
WHAT ELSE YOU SHOULD KNOW: A total knee replacement is commonly used for single compartment arthritis because it’s thought that a partial replacement is more likely to require a re-operation, which can include a revision to replace the original implant as a result of a shorter device lifespan, infection, or persistent pain. However, this study suggests the rates of re-operation for both total and partial replacements are about the same after five years. Currently, only about 10 percent of knee replacements performed in the United States are partial.
WHAT YOU SHOULD DO: Both partial and total knee replacements have their own benefits and risks, and partial knee replacement may not be suitable for some patterns of osteoarthritis, nor is it used for rheumatoid arthritis. If you’re facing a future knee replacement, have a discussion with your orthopedist about the pros and cons for each procedure. And, regardless of the type of procedure you choose, it’s best to have a surgeon who performs many of these types of surgeries and at a hospital with a high volume of knee replacements.