When patients think of knee replacement surgery, they can be intimidated by the thought of having their entire knee replaced. Our knees are integral to walking, so it’s not unnatural to have questions about a procedure on such an essential part of our bodies.

As one of the most common orthopedic surgeries, total knee replacement surgery is safe, effective, and widely used to alleviate pain and improve mobility in patients with a variety of conditions.

However, replacing the entire knee joint is not always necessary, especially if the joint is only partially damaged. As a complex hinge, our knees have multiple sections and moving parts. Each of these separate components can suffer damage independently while the rest of the joint remains intact.

Travis Clegg, M.D., a board-certified orthopedic surgeon specializing in hip and knee replacement, emphasizes that advances in modern knee surgery now allow surgeons to repair sections of the knee without needing to replace the entire structure. Dr. Clegg says, “a partial knee replacement is where there’s arthritis primarily in one part of the joint. We go in and resurface one particular part of the joint without damaging any other ligaments or knee muscles.”

In this article, we’ll go over what patients can expect from partial knee replacement surgery, how it compares to total knee replacement surgery, and how long targeted knee repairs can last.

Total Knee vs. Partial Knee—What’s the Difference?

Knee replacement surgery has come a long way over the past five decades. More than 800,000 total knee replacement procedures are performed in the U.S. each year. Today, surgeons have the option of either replacing just a portion of your knee or the entire joint with a prosthetic device.

One in five Americans develop arthritis in their knees, a disease commonly caused by normal wear and tear on joints. As arthritis progresses, the connective tissues wear away, causing the bones to rub together. The friction between the bones can be extremely painful and cause stiffness in the joint that restricts mobility. 

To relieve these issues, surgeons typically pursue less invasive options, sometimes for years, to help patients eliminate pain and keep the joint functioning. Eventually, most patients turn to proven surgical procedures to restore their mobility and release them from life-altering pain. 

As surgeons assess the damaged joint, they may find that only certain portions of the knee are damaged. Many times, early-stage arthritis does not affect the entire joint but just a portion of the knee. In these cases, surgeons may recommend partial removal of damaged parts instead of a total knee replacement.

As the names suggest, the two use a similar approach but differ in the extent of their intervention: 

  • Total Knee Replacement – surgically removing the entire joint to replace it with a new plastic, metal, or ceramic artificial prosthetic joint
  • Partial Knee Replacement – the removal and replacement of individual sections of the knee

The knee joint consists of three primary bones:

  1. Thigh Bone (femur)
  2. Kneecap (patella)
  3. Shinbone (tibia)

When surgeons consider performing a partial knee replacement, they look at the three main compartments within the knee’s structure to identify the extent of the damage in each:

  1. Inner Compartment (medial layer)
  2. Outer Compartment (where the femur and tibia meet)
  3. Patellofemoral Compartment (where the patella resides in front of the femur)

Each of these compartments can be affected by arthritis. If all three compartments are damaged, and your surgeon recommends surgical removal and replacement, full knee surgery is often the best choice. However, if just one of the compartments is affected with arthritis, why would you destroy healthy tissue with a full knee replacement? In these instances, it is preferable to keep existing sections of the knee intact to preserve as much of the patient’s original mobility as possible.

The medial compartment is where knee osteoarthritis most often occurs. Today, surgeons can clean out just this section and replace the damaged compartment (not the full knee) with a prosthetic. By limiting surgery to a smaller area, partial knee replacements allow you to heal faster while preserving the knee’s natural function and feel.

The primary approach we use when considering partial knee replacement is an unicompartmental partial knee replacement which is the removal and replacement of just one of the three compartments of the knee.

What Are the Benefits of Partial Knee Replacement Surgery?

When knee arthritis disrupts your life, it can negatively impact every aspect of your life, making even basic chores and activities painful and difficult. Depending on the severity of the damage in your knee, partial knee replacement surgery can alleviate these symptoms by removing the diseased section of the knee while leaving the healthy sections intact. The benefits include:

  • Faster recovery from surgery
  • Increased range of knee motion 
  • Less pain after surgery
  • Less risk of surgical complications
  • Less trauma to knee tissue
  • Preservation of any healthy bone or connective tissues
  • Reduced blood loss
  • Shorter hospital stay

Partial knee replacement can address the specific site affected by arthritis without harming tissue that is working fine and healthy. But how long does a partial replacement last?

How Long Does a Partial Knee Replacement Last?

Prosthetic knee replacements are most often made of metal, plastic, or ceramic. While sturdy and reliable, these materials can wear out over time and may need to be replaced. However, the longevity of these prosthetics has increased dramatically over the past twenty years—for many patients, they can last the rest of their lives without causing issues. As Dr. Clegg says, “Recent data has come out that shows at 30 years, about 91% of partial knee replacements with modern implants are still working.” 

He’s right—the prosthetics and the surgical techniques Dr. Clegg and other orthopedic teams use are always improving, offering patients long-lasting relief and improved mobility for some of the most severe knee conditions. 

However, what factors affect the longevity of these devices? Can lifestyle changes improve their lifespan? 

How long a prosthetic lasts largely depends on the type of material. However, working with a skillful surgeon can also make a difference—a properly fitted prosthetic produces less friction, limiting wear to the replacement and improving its longevity. This is one of the main reasons why it’s important to work with an experienced surgeon who can adjust the fit to work synergistically with your body. 

Years of experience are key to success, which is why so many patients choose Dr. Clegg and his staff. Each year, our talented team repairs hundreds of knees, getting patients just like you back on their feet and living pain-free. 

Access relief today by scheduling a consultation with one of our team members or by calling us at 812-935-5633.