Partial Knee Replacement
Partial Knee Replacement or Unicondylar Knee Replacement simply means that only a part of the knee joint is replaced through a smaller incision than would normally be used for a total knee replacement.
Unicondylar Knee Replacements have been performed for decades and developments in implant design, instrumentation and surgical techniques have resulted in this approach being considered as the procedure of choice for unicompartmental arthritis.
Unicondylar Knee Replacement Approach
Your knee is divided into three major compartments:
- The medial compartment ( the inside part of the knee)
- The lateral compartment ( the outside of the knee)
- The patellofemoral compartment ( the front of the knee between the kneecap and thighbone)
In a uni-compartmental knee replacement, only the damaged compartment is replaced with metal and plastic. The healthy cartilage and bone in the remainder of the knee is left alone.
Advantages of Partial Knee Replacement
The benefits of a Unicondylar Knee Replacement over a total knee replacement (TKR) are:
- Tissue preserving operation with less bone removal,
- Faster recovery
- Smaller incision,
- Better range of movement
- A more natural feeling knee
- Minimal blood loss
- Better function
Candidates for Partial Knee Replacement
Patients suitable for Partial Knee Replacement are those who are:
- Suffering pain
- Limited in their activity level by their arthritic knee
- Clinically proven to have only one diseased compartment (X-ray and MRI confirmed)
- Not suffering with severe angular deformity
- Not suffering inflammatory arthritis e.g. rheumatoid arthritis
- Not suffering an unstable knee
- Not previous osteotomy patients
While a partial knee replacement can be considered at any age, the outcome of the surgery tends to depends on the type of arthritis, rather than your age.
- Younger patients would benefit from bone preservation which is helpful if you need revision surgery at a later stage
- Older patients would benefit from a smaller minimally invasive operation with less pain and bleeding, with an easier, faster recovery.
Partial Knee Replacement Surgery
The procedure is designed to be performed with minimal local trauma
- A small incision around 7-10 cm is made to expose the knee joint
- The bone ends of the femur and tibia are prepared
- Trial components are then inserted and tested for accurate fit, stability and range of motion
- The final components are placed with or without cement
- The knee is then carefully closed and
- The knee dressed and bandaged.