What to know about partial knee replacements
Knee pain can be debilitating, particularly when caused by arthritis or injury that limits mobility and affects quality of life. For some patients, joint preservation through a partial knee replacement offers an effective alternative to full joint replacement, restoring function while maintaining more of the natural knee structure. In this article, consultant orthopaedic surgeon Mr Hersh Deo explains who may benefit from a partial knee replacement, and how it differs from a total knee replacement.
Why might someone need a partial knee replacement?
A partial knee replacement is typically recommended for patients whose arthritis or damage is limited to one part of the knee. The knee is divided into three parts: medial (inside), lateral (outside), and patellofemoral (under the kneecap). When only one part is affected — often the medial side — a partial replacement may be suitable.
Common causes include:
- Osteoarthritis: The most common reason for partial knee replacement, affecting the cartilage and bone in one part.
- Trauma or injury: Past injuries can lead to uneven wear in specific areas of the joint.
- Avascular necrosis: Where the blood supply to a section of bone is reduced or lost, leading to joint collapse in one area.
Patients are typically assessed based on their pain, mobility, alignment of the knee, and the extent of damage, confirmed through imaging such as X-rays or MRI scans.
What is the difference between a partial and a total knee replacement?
A total knee replacement involves resurfacing all three parts of the knee joint with metal and plastic implants. It’s a well-established procedure for patients with widespread arthritis or deformity.
In contrast, a partial knee replacement addresses only the damaged area, leaving the healthy bone, cartilage, and ligaments intact. The procedure is less invasive, preserving more of the patient’s natural knee and allowing for more natural movement post-surgery.
Not everyone is a candidate for a partial replacement. It is most successful in patients with:
- Isolated damage
- Intact ligaments, particularly the anterior cruciate ligament (ACL)
- Minimal deformity and good knee stability
Benefits of partial knee replacement
For the right patient, partial knee replacement offers several advantages:
- Smaller incision and less tissue disruption: The surgery is typically performed through a smaller incision, leading to less trauma to the surrounding muscles and ligaments.
- Faster recovery: Many patients experience quicker rehabilitation, shorter hospital stays, and a faster return to normal activities.
- More natural knee function: Because much of the knee is preserved, many patients report a more natural feel compared to a total knee replacement.
- Lower risk of complications: There may be a reduced risk of blood loss, infection, and stiffness.
Disadvantages and considerations
Despite its benefits, partial knee replacement is not suitable for everyone and has some limitations:
- Potential for future surgery: If arthritis develops in other portions of the knee, a revision knee replacement may be needed later.
- Longevity: While modern implants are durable, they may not last as long in younger, more active patients.
- Surgical precision required: The procedure demands high surgical accuracy. It is important to be treated by an experienced orthopaedic surgeon with specific expertise in joint preservation.
Discussing the risks and benefits with a specialist is vital to determining the most appropriate treatment based on individual needs and lifestyle.
Choosing the right path to knee health
Partial knee replacement is a proven solution for selected patients who wish to retain as much of their natural joint as possible. It combines modern surgical techniques with a focus on recovery, mobility, and long-term comfort.
With the support of experienced orthopaedic care and a tailored rehabilitation programme post-surgery, many patients find they can return to walking, recreational activities, and an improved quality of life with less pain and greater confidence.