The partial knee replacement

If you’re struggling to keep active because of a long standing knee issue, then you may want to read what Mr Veysi – an experienced orthopaedic surgeon based in Leeds who specialises in various hip and knee issues thinks is important when assessing and treating knees which have been diagnosed with osteoarthritis. Here he tells us about the clinical reasoning that underpins why a surgeon would choose a partial knee replacement (PKR) over a total knee replacement (TKR).

Introduction

The knee is a complex joint made of three compartments. All three compartments can be involved in arthritis either in isolation or in combination. Treatment of knee arthritis should always involve lifestyle changes, including weight loss and exercise, and simple pain killers. Surgery should only be considered if these measures fail to control the symptoms. The mainstay of surgery for knee arthritis is a knee replacement which can be broadly divided into two types, a total and partial knee replacement.

A total knee replacement (TKR) involves replacing all three compartments of the knee. This is by far the most common type of knee replacement and achieves great results in the majority of patients. A partial knee replacement (PKR) is when only one of the three knee compartments is replaced. It is suitable under certain conditions and has some advantages over a TKR.

Who is suitable for a partial knee replacement?

In some studies, it is reported that up to 60% of people with knee arthritis are suitable to receive a PKR.

Important points to consider are:

  • A PKR is possible when arthritis affects only one compartment of the knee. This can be any compartment, including the Patello-femoral compartment (part of the knee joint behind the kneecap, often causing pain on the front of the knee).
  • It is only possible in patients with Osteoarthritis, and not suitable for patients with an inflammatory arthritis, such as rheumatoid arthritis.
  • It requires the ligaments in the knee to be normal. People with previous ligament ruptures due to trauma, and ligament contractures, often due to long standing deformity, are not suitable for a PKR.

A common mistake is to consider PKR for young people only. Older people get equally good results with PKR.

Advantages of partial knee replacements

The advantages of PKR are because of two main facts; the knee ligaments and the undamaged parts of the knee are left intact. Consequently, the knee maintains its normal mechanics and function.

Advantages as a result of these include:

  • PKR can be done through a minimally invasive approach
  • There is a slightly lower risk of infection with a PKR
  • The knee often has a better range of movement than it would with a TKR
  • Recovery tends to be quicker. This is especially the case in older patients
  • Because the other two compartments of the knee are left untouched, any future revision surgery tends to be more straight forward. This is important in patients who need surgery at a younger age

Risks of partial knee replacements

There is a misconception that PKR is a lesser operation to TKR. This is not the case, and most risks are identical for the two operations. In general, these include:

  • Infection
  • Pain and stiffness
  • Blood clots in the legs (DVT) and lungs (PE)

Registry data also suggests that there is slightly increased risk of a re-operation after a PKR. This is due to a complex series of reasons, and it is highly recommended that your follow-up after a PKR is completed by the operating surgeon, or a surgeon who is experienced in PKR to avoid unnecessary re-operations.

Conclusion

Due to modern advancements in knee surgery and treatment there are now a range of treatment options available to patients who have been diagnosed with osteoarthritis of the knee. A partial knee replacement completed by an excellent clinician like Mr Veysi can be a great choice of treatment but only after weighing the risks against the benefits and after excellent dialogue with your orthopaedic surgeon.

To find out whether we think your issue is likely to be osteoarthritis and therefore whether an orthopaedic surgeon like Mr Veysi can help then simply fill in your clinical details for free on our online form and let us help get you on the road to recovery.