Unicondylar (Partial Knee) Replacement

Unicondylar knee replacement, also known as partial knee replacement, is a surgical procedure designed to treat localized knee arthritis or damage. Unlike total knee replacement, which involves replacing the entire knee joint, partial knee replacement focuses on replacing only the damaged compartment of the knee. This minimally invasive approach offers several benefits, including a quicker recovery and preservation of more natural knee function.

What Is Unicondylar (Partial) Knee Replacement?

Unicondylar knee replacement is a type of knee arthroplasty that targets only one compartment of the knee. The knee is divided into three compartments: the medial (inside), lateral (outside), and patellofemoral (front) compartments. In cases where arthritis or damage is confined to one compartment, a partial knee replacement can be performed to replace the damaged area with a prosthetic implant while preserving the healthy bone and cartilage in the other compartments. This procedure is less invasive than a total knee replacement and can lead to a more natural-feeling knee post-surgery.

Who Are Ideal Candidates for Unicondylar Knee Replacement?

– Patients with Localized Knee Arthritis: Individuals with arthritis limited to one compartment of the knee.

– Patients with Stable Knee Ligaments: Those with intact ligaments, particularly the anterior cruciate ligament (ACL).

– Patients with Normal Weight: Individuals with a body mass index (BMI) within a healthy range.

– Patients with Minimal Knee Deformity: Those with little to no deformity in the knee joint.

– Patients Seeking a Quicker Recovery: Individuals who prefer a less invasive procedure with a faster recovery time.

What Conditions Lead to the Need for Unicondylar Knee Replacement?

– Medial Compartment Osteoarthritis: Arthritis affecting the inside compartment of the knee.

– Lateral Compartment Osteoarthritis: Arthritis affecting the outside compartment of the knee.

– Isolated Patellofemoral Arthritis: Arthritis affecting the front compartment of the knee.

– Post-Traumatic Arthritis: Joint damage resulting from previous injuries confined to one compartment.

– Avascular Necrosis: Bone tissue death due to inadequate blood supply, localized to one compartment.

– Degenerative Joint Disease: Progressive wear and tear confined to a single knee compartment.

– Failed Previous Surgeries: Complications or residual issues from prior knee procedures limited to one compartment.

What Happens During Unicondylar Knee Replacement Surgery?

During unicondylar knee replacement surgery, the patient is typically placed under general anesthesia or regional anesthesia with sedation to ensure comfort and a pain-free experience throughout the procedure. The surgeon makes a small incision over the knee to access the damaged compartment.

The damaged portions of the femur (thighbone) and tibia (shinbone) within the affected compartment are carefully removed and reshaped to fit the prosthetic components. The artificial knee components, which are typically made of metal and plastic, are then implanted. These components are secured in place with bone cement or press-fit to allow the bone to grow into the implant. The surgeon ensures that the new joint is properly aligned and moves smoothly. Once the prosthetic components are in place, the incision is closed with sutures or staples, and a bandage is applied to protect the area.

What Are the Benefits of Unicondylar Knee Replacement?

– Minimally Invasive: Smaller incisions and less tissue damage compared to total knee replacement.

– Reduced Pain: Less postoperative pain due to minimal disruption of surrounding tissues.

– Faster Recovery: Quicker return to normal activities and reduced downtime.

– Preservation of Natural Knee Function: Maintains more of the knee’s natural anatomy and function.

– Improved Joint Stability: Enhanced stability due to preservation of healthy bone and ligaments.

– Better Cosmetic Results: Smaller scars due to smaller incisions.

– Lower Risk of Complications: Reduced risk of infection and other complications associated with more extensive surgeries.

What Are the Risks and Complications of Unicondylar Knee Replacement?

– Joint Stiffness: Reduced range of motion due to scar tissue formation.

– Implant Loosening: Over time, the implant may become loose.

– Fractures: Risk of bone fractures during or after surgery.

– Adverse Reaction to Anesthesia: Complications related to the use of anesthesia.

– Persistent Pain: Ongoing pain despite surgical intervention.

– Progression of Arthritis: Arthritis may develop in other compartments of the knee over time if the ACL is injured.

How Long Is the Recovery Period After Unicondylar Knee Replacement Surgery?

The recovery period after unicondylar knee replacement surgery is generally shorter and less intensive than recovery from a total knee replacement. Most patients can expect to stay in the hospital for one to two days following the procedure. Pain and swelling are managed with medications and ice packs. Physical therapy usually begins soon after surgery and is limited compared to a total knee replacement.

Patients are often encouraged to bear weight on the operated leg almost immediately, and many can resume light activities within a few weeks. Recovery time can range from several weeks to several months, with most patients achieving significant improvements in pain relief and function within 6-12 weeks. Full recovery, including a return to more demanding physical activities, can take up to six months or longer. Regular follow-up appointments with the surgeon are essential to monitor progress and ensure proper healing.

How Effective Is Unicondylar Knee Replacement Surgery?

Unicondylar knee replacement surgery is highly effective in providing pain relief and improving joint function. Many patients experience significant improvements in their quality of life and can return to their normal activities following surgery. The success of the surgery depends on various factors, including the patient’s overall health, adherence to post-operative care, and the skill of the surgeon.

What Are the Long-Term Outcomes of Unicondylar Knee Replacement?

The long-term outcomes of unicondylar knee replacement are generally positive, with many patients experiencing lasting pain relief and improved joint function. Successful replacement of the damaged compartment can prevent further damage to the surrounding tissues and reduce the risk of developing additional joint problems. However, it is essential to follow a comprehensive rehabilitation program and avoid activities that may stress the knee joint to ensure the best long-term results.

Dr. Ponnanna specializes in partial knee replacement and preserves healthy tissue and provides targeted relief. Expert care for localized knee damage. Schedule your appointment today for effective treatment.