MAKO Robot-Assisted Partial Knee Replacement

Partial or Unicompartmental Knee Replacement is a surgical procedure that involves the replacement of only the diseased surface of the joint instead of the entire joint. The knee can be divided into three compartments: patellofemoral, the compartment in the front of the knee between the knee cap and thigh bone, medial compartment, on the inside portion of the knee, and lateral compartment which is the area on the outside portion of the knee joint.

 

Associate Professor Harvie may recommend Partial Knee  Replacement if your arthritis is limited to only one compartment of the knee.

What does MAKO Robot-Assisted Technology actually do?

Associate Professor Harvie currently performs all Partial Knee Replacements using MAKO Robot-Assisted Technology. This system utilises pre-operative CT scans to form three-dimensional model of your knee. During the operation the surgeon collects information about the soft tissue balance of the knee. This information is combined with the CT scan and allows the surgeon to perform a virtual operation on the computer.

 

Once the optimum position has been ascertained for the femoral (thigh bone) component and the tibial (leg bone) component, the robotic arm is then utilised to mill the bone ends and allow placement of the implants. This technology has been utilised in the United States since 2006. It was introduced into Australia in 2015. The indications for Partial Knee Replacement are not changed by the use of the robot. Accuracy of implantation has been shown to be improved whilst personalising the positon of components to the patient’s own soft tissues. This means less ‘cutting’ of tissue, less post-operative pain and faster recovery.

Why use MAKO Robot-Assisted Technology?

Currently all robotic cases in Australia are closely followed up to determine if this technology will decrease the previously high revision rates seen in Partial Knee Replacement. These have previously had a 20% failure rate at 10 years post-surgery compared to less than 6% with a Total Knee Replacement. 

 

It has been shown this is due to either the implant coming loose or progression of the disease to the other side of the knee. I am confident that Robotic Assistance will help me place the implants more accurately, which should decrease the rate of implants coming loose. The robot also assists me in balancing the knee throughout the full range of motion preventing overloading of the other parts of the knee. This together with an appropriate selection of patients prevents revision due to progression of disease.

 

Research recently published as well as Australian National Joint Registry Data shows that the MAKO Robot-Assisted Partial Knee Replacement in currently outperforming all other Partial Knee Replacements at 3 – 5 years after surgery.

 

Evidence also exists to show patients undergoing MAKO Robot-Assisted Partial Knee Replacement:

 

  • Experience less postoperative pain
  • Have decreased opiate analgesia requirements
  • Rehabilitate quicker
  • Have increased range of movement
  • Have a shorter hospital stay when compared to other Partial Knee Replacements.

Who is no suitable for a Partial Knee Replacement?

  • Patients with arthritis affecting more than one compartment
  • Patients with severe angular deformity
  • Patients with inflammatory arthritis e.g.  rheumatoid arthritis
  • Patients with an unstable knee
  • Patients who have had a previous osteotomy
  • Patients who are involved in heavy work or contact sports

Will I have much pain after my MAKO Robot-Assisted Total Knee Replacement?

Traditionally Total Knee Replacement has been noted as being a ‘painful procedure’. Anesthetists who specialise in pain control have made major advances in recent years in regard to eliminating or at least substantially reducing discomfort from surgery. A ‘multimodal’ (multiple simultaneously combined techniques) will be utilised to turn off pain pathways and to then keep you comfortable during your recovery.

 

With the use of MAKO Robot-Assisted technology evidence exists and my personal experience is that patients experience less pain and require less post-operative pain medication than with other technologies I have utilised. The reason for this is very simple. The MAKO technology results in less soft tissue ‘cutting’ which translates to less pain.

 

You may still experience some mild discomfort but our patients can generally stand and walk within hours of surgery and usually report than any discomfort is very manageable and that the procedure is very well tolerated.

What are the Risks and Complications?

As with any major surgery, there are potential risks involved. The decision to proceed with the surgery is made because the advantages of surgery outweigh the potential disadvantages. It is important that you are informed of these risks before the surgery takes place.  Complications can be medical (general) or local complications specific to the Knee. Medical complications include those of the anesthetic and your general well being. Almost any medical condition can occur so this list is not complete.

 

Complications include:

 

  • Allergic reactions to medications
  • Blood loss requiring transfusion with its low risk of disease transmission
  • Heart attacks, strokes, kidney failure, pneumonia, bladder infections
  • Complications from nerve blocks such as infection or nerve damage
  • Serious medical problems can lead to ongoing health concerns, prolonged hospitalization or rarely death

Infection can occur with any operation. In the hip this can be superficial or deep. Infection rates are approximately 1%. If it occurs, it can be treated with antibiotics but may require further surgery. Very rarely your hip may need to be removed to eradicate infection.

These can form in the calf muscles and can travel to the lung (Pulmonary embolism). These can occasionally be serious and even life threatening. If you get calf pain or shortness of breath at any stage, you should notify your surgeon.

Ideally, your knee should bend beyond 115 degrees but on occasion, may not bend as well as expected. Sometimes manipulations are required. This means going to the operating room where the knee is bent for you while under anesthetic.

The plastic liner eventually wears out over time, usually over 10 to 15 years, and may need to be changed. Alternatively the remainder of your own knee may wear out requiring revision to a Total Knee Replacement.

Fractures or breaks can occur during surgery or afterwards if you fall. To repair these, you may require surgery.

The operation will always cut some skin nerves, so you will inevitably have some numbness around the wound. This does not affect the function of your joint. You can also get some aching around the scar. Vitamin E cream and massaging can help reduce this. Occasionally, you can get reactions to the sutures or a wound breakdown that may require antibiotics or rarely, further surgery.

The knee may look different than it was because it is put into the correct alignment to allow proper function.

Your leg will be restored to it’s original length as the deformity caused by wearing of the knee has been corrected.

There are a number of ligaments surrounding the knee. These ligaments can be torn during surgery or break or stretch out any time afterwards. Surgery may be required to correct this problem. This problem is minimised with Robotic Assistance.

Rarely these can be damaged at the time of surgery. If recognized they are repaired but a second operation may be required. Nerve damage can cause a loss of feeling or movement below the knee and can be permanent.

Discuss your concerns thoroughly with your Orthopaedic Surgeon prior to surgery.

Summary

Surgery is not a pleasant prospect for anyone, but for some people with arthritis, it could mean the difference between leading a normal life or putting up with a debilitating condition. Surgery can be regarded as part of your treatment plan it may help to restore function to your damaged joints as well as relieve pain. Surgery is only offered once non-operative treatment has failed. It is an important decision to make and ultimately it is an informed decision between you, your surgeon, family and GP. Although most people are extremely happy with their new knee, complications can occur and you must be aware of these prior to making a decision. If you are undecided, it is best to wait until you are sure this is the procedure for you.