Unicompartment (partial) Knee Replacement

Knee Anatomy

Knee is a complex joint formed by femur, tibia and patella (knee cap). Ligaments (ACL, PCL, MCL and LCL) give primary stability to the knee joint. Medial and lateral meniscus; provide shock absorbing function.

There are three compartments or articulations in the knee joint.

  • Medial compartment (inside part of knee)
  • Lateral compartment (outside part of knee)
  • Patello-femoral compartment (knee-cap and thigh bone)

Mr Shalinder Sadiq will be happy to discuss this in detail with you during your consultation.

Knee Osteoarthritis

Osteoarthritis is age related wearing out of cartilage resulting in pain in the knee joint. It shows as joint space narrowing, with ‘bone on bone’ articulation on x-rays.

Knee osteoarthritis can affect one or more compartments of the knee joint. The ligaments usually remain ‘intact and functional’ in arthritis of knee. Medial compartment is by far the commonest compartment of knee to get affected by osteoarthritis.


During knee replacement surgery, damaged bone and cartilage is replaced with prosthetic components. In unicompartment (partial) knee replacement, only the diseased compartment of knee joint is replaced. This procedure is an alternative to total knee replacement for patients whose disease is limited to one compartment of the knee. The healthy cartilage and bone, as well as all the ligaments of the knee are preserved.


Multiple studies show that majority of patients have good results with unicomparment knee replacement. Advantages over total knee replacement include:

  • quicker recovery
  • less pain after surgery
  • less blood loss
  • knee feels more natural than total knee replacement
  • knee likely to bend (flex) better than total knee replacement


  • potential need for more surgery (after many years)

Signature Oxford Knee

Mr Shalinder Sadiq uses Oxford Signature ‘personalized guides’ for performing unicomparment knee replacement. The patient specific ‘personalized guides’ are designed and manufactured after performing MRI scan for your knee. This technology also manufactures a life size 3 D (3 dimensional) model of your knee, which allows the surgeon to understand bony anatomy of your knee. For further information please see

After you operation

After your operation, we will help you to walk on the day of (or occasionally day after) surgery under guidance of a physiotherapist. Expected stay in hospital is usually 3-4 days. You might need a period of physiotherapy after your discharge from the hospital.

Mr Shalinder Sadiq will review you in his rooms 2 weeks after your operation. Subsequent follow up is 6 weeks after your operation. If you think something is not right, please see link ‘recovery after operation’.

Mr Sadiq reviews his joint replacement patients every 12 months. Please contact us on 6234 7511 or email if you need assistance or you think something is not right.