- SPECIALIST ORTHOPAEDIC SURGEON | MELBOURNE, VIC | ALBURY, NSW | MORNINGTON, VIC |
- 03 9421 6133
- Melbourne & Mornington VIC |
- Albury, NSW
Partial (Uni-Compartmental) Knee Replacement
A less invasive surgical option for arthritis affecting one part of the knee
Unicompartmental knee replacement, also known as partial knee replacement, is a procedure designed for patients with osteoarthritis affecting only one part of the knee joint. Unlike a total knee replacement, which resurfaces all three compartments of the knee, this targeted approach replaces just the damaged portion, while preserving the healthy bone, cartilage, and supporting ligaments.
For the right patient, partial knee replacement may offer a shorter recovery, reduced post-operative pain, and a more natural-feeling joint than a full knee replacement. Dr Jason Hockings offers this advanced surgical option for patients who meet specific criteria following comprehensive clinical and imaging assessment.
Understanding your knee joint (anatomy)
The knee is divided into three key compartments:
- Medial compartment – the inner side of the knee (most commonly affected by arthritis)
- Lateral compartment – the outer side
- Patellofemoral compartment – where the kneecap meets the thighbone
In many patients with knee osteoarthritis, only one compartment, typically the medial compartment, is damaged, while the rest of the knee remains relatively healthy. If you have arthritis limited to a single compartment, you may not need a total knee replacement. In these cases, unicompartmental (partial) knee replacement may be recommended as a less invasive alternative that preserves your native knee structures.
Who is a candidate for partial knee replacement?
Not everyone with knee arthritis is suited to a partial knee replacement. Dr Hockings may consider this option if:
- Arthritis is limited to a single compartment (most often the medial side)
- Knee ligaments are intact, especially the ACL
- Range of motion is good and the joint remains stable
- There are no significant deformities or damage in the other compartments
- Non-surgical treatments like physiotherapy or joint injections are no longer effective
X-rays and other imaging, such as MRI or weight-bearing scans are used to confirm whether this surgical option is appropriate for you.
Benefits of unicompartmental knee replacement
For carefully selected patients, partial knee replacement surgery offers several potential benefits compared to a total knee replacement:
- Minimally invasive – Smaller incisions and less disruption to healthy tissues
- Faster recovery – Shorter hospital stay and quicker return to mobility
- Less post-operative pain – Due to preservation of bone, ligaments, and joint capsule
- Natural knee feel – The ACL and other ligaments are left intact, helping retain a natural movement pattern
- Lower complication rates – Reduced risk of blood loss and infection in some patients
- High satisfaction – Many patients report excellent outcomes and knee function, especially during walking, bending, and daily activity
The unicompartmental knee replacement surgical procedure: what to expect
Partial knee replacement is typically performed under general or spinal anaesthesia in a hospital setting. Dr Hockings uses precise surgical techniques to remove only the damaged tissue while preserving the rest of your knee.
Key steps include:
- A small incision is made over the affected area of the knee
- Damaged cartilage and bone are carefully removed from the affected compartment
- The joint surfaces are reshaped to accommodate the implant
- A metal cap is placed on the end of the femur (thighbone), and a metal plate is placed on the top of the tibia (shinbone)
- A plastic spacer is inserted between the metal components to allow smooth, pain-free movement
- The incision is closed once stability and movement are confirmed
The remaining two compartments and your natural ligaments, including the anterior cruciate ligament (ACL) are preserved to maintain as much of your native knee biomechanics as possible.
Recovery and rehabilitation following partial knee replacement surgery
One of the main advantages of partial knee replacement is a generally faster and smoother recovery compared to total knee replacement.
You may be considered for RFA if you:
- You’ll usually begin walking with assistance on the day of surgery or the following morning
- Most patients return home within 1–2 days
- You may use crutches or a walker for the first 1–2 weeks
- A structured physiotherapy program will help you regain knee strength, mobility, and balance
- Most people return to daily activities within 4–6 weeks
- Low-impact exercises such as walking, cycling, or swimming are encouraged after recovery
High-impact sports and activities that involve running, jumping, or twisting are usually discouraged to help prolong the life of the implant.
Dr Hockings and your physiotherapy team will guide your rehabilitation to ensure the best possible long-term outcome.
Unicompartmental knee replacement risks and potential complications
Although partial knee replacement is considered a safe and effective procedure, all surgery carries some risks. Dr Hockings will discuss the risks specific to your situation during your consultation.
Possible complications include:
- Infection at the surgical site
- Blood clots (DVT) in the legs or lungs
- Knee stiffness or limited range of motion
- Loosening or wear of the implant over time
- Progression of arthritis in the other compartments of the knee
- Need for revision surgery or conversion to a total knee replacement in the future
By selecting the right patients and using modern surgical techniques, many of these risks can be minimised.
How long does a partial knee replacement last?
Modern partial knee replacements have shown excellent longevity. For many patients, the implant lasts 10 to 15 years or longer, especially if:
- You maintain a healthy body weight
- You avoid high-impact or strenuous activity
- You adhere to your post-operative rehabilitation plan
If arthritis later develops in the other parts of the knee, a ‘revision’ to total knee replacement may become necessary. Dr Hockings will monitor your progress during follow-up appointments to ensure long-term success.
Is partial knee replacement right for you?
If knee pain is significantly impacting your lifestyle and is caused by arthritis limited to one compartment, and if non-operative treatments have not brought adequate relief, unicompartmental knee replacement may offer an excellent alternative to total knee replacement.
During your consultation, Dr Jason Hockings will perform a detailed assessment, review your imaging, and provide you with personalised advice on whether this procedure aligns with your health goals, lifestyle, and long-term joint preservation.
If you’re experiencing ongoing pain, stiffness, or reduced movement that is affecting your daily activities or quality of life, a thorough orthopaedic assessment can help determine the cause and guide the most appropriate treatment options for your situation.