Unicompartmental Knee Replacement

Unicompartmental knee replacement (UKR) is a surgical procedure used to treat arthritis that is limited to a single compartment of the knee. In this procedure, only the damaged compartment of the knee is replaced with an artificial implant, rather than replacing the entire knee joint.

Indications

UKR is typically recommended for patients who have:

• Arthritis that is limited to a single compartment of the knee (either the medial or lateral compartment)
• Moderate to severe pain and stiffness in the affected knee
• Failed to respond to conservative treatments such as physical therapy, medications, and injections
• A relatively normal alignment of the knee joint
• No significant ligament instability or deformity

Surgical Procedure

The UKR procedure typically involves the following steps:

1. A small incision is made in the skin to access the affected compartment of the knee
2. The damaged cartilage and bone are removed from the joint
3. An artificial implant, consisting of a metal and plastic component, is inserted into the joint to replace the damaged area
4. The implant is secured to the surrounding bone using cement or other fixation methods
5. The incision is closed and the knee is dressed with a bandage

Types of Implants

There are several types of implants used in UKR, including:

• Fixed-bearing implants: These have a fixed bearing surface that does not move
• Movable-bearing implants: These have a mobile bearing surface that allows for greater movement and flexibility
• Customized implants: These are designed to match the individual patient's anatomy and can be made using 3D printing technology

Benefits

The benefits of UKR include:

• Less tissue damage and trauma compared to total knee replacement (TKR)
• Faster recovery time and less post-operative pain
• Better preservation of natural knee function and movement
• Lower risk of complications such as infection, blood clots, and nerve damage

Risks and Complications

As with any surgical procedure, there are risks and potential complications associated with UKR, including:

• Infection
• Blood clots
• Nerve damage
• Implant failure or loosening
• Continued pain or stiffness in the knee

Recovery and Rehabilitation

The recovery process for UKR typically involves:

• Several days of hospitalization after surgery
• A period of rest and immobilization to allow the knee to heal
• Physical therapy to regain strength, flexibility, and range of motion in the knee
• Pain management using medications and other interventions

Outcomes and Prognosis

The outcomes and prognosis for UKR are generally good, with:

• High success rates in terms of pain relief and functional improvement
• Low revision rates compared to TKR
• Good long-term durability of the implant, with many patients experiencing 10-15 years or more of satisfactory function