Robotic hip surgery: is it the future?

Total Hip Replacement with MAKO robot assisted

It has been heralded as the future of orthopaedic surgery, with manifold benefits for the patient and Mr Simon Bridle is delighted to now be able to offer MAKO robotic-assisted hip surgery to his patients at the Fortius Joint Replacement Centre at the Cromwell Hospital in London.

Hip replacement surgery has been performed for over 50 years with great strides made in terms of implant material and technique and current day operations are generally considered very successful and result in a great improvement in the patient’s quality of life. Inaccurate placement of the prosthetic components often contributes to the hip replacement failing.  Component malalignment can result in instability, impingement or leg length discrepancies. The introduction of robotic guidance systems can help the orthopaedic surgeon plan and place the prosthesis with a much greater degree of accuracy.

Using 3D computer mapping, the implant can be aligned precisely – to within fractions of a millimetre. As Simon explains, there is strong evidence that with our standard techniques, our ability to implant hip materials does not compare to using the robotic guidance system.

Precise acetabular cup placement is a key factor in a successful total hip replacement.  In a review of almost 2,000 cases at Massachusetts General Hospital, a 2011 study found that acetabular cups were placed in the ideal position only 47% of the time. In another study that compared 50 MAKO assisted procedures to the same number of conventional hip replacements, it was found that 92% – 100% of MAKO hip replacements were in the two safe zones evaluated, compared to 62% – 80% of conventional surgeries.

How does robot-assisted hip surgery work

The pre-operative planning stage with the robotic device means that you can more accurately implant the components during the surgical procedure. CT scans are taken which allow the surgeon to map the bony anatomy.

Then, when the patient is on the operating table, special cameras in the theatre take various reference points, matching the actual pelvis and femur to the CT images loaded into the computer. This adds probably about 15 minutes to the actual procedure; however, as it will probably cut a few minutes off the surgical process, there is very little difference for the patient.

It’s important, though, that patients realise that the robot is not taking over from the surgeon! We are just using the available technology to enhance our skills, but we are still performing the actual incisions and placement of the prosthesis.

The benefits of robot-assisted hip surgery

From Simon’s anecdotal experience, the most common complaint after surgery is leg length inequality. Leg length is affected by how far you push the femoral component into the bone and anything more than a centimetre difference is noticeable. It is possible to deal with this problem with a shoe raise but most patients find this unsatisfactory, particularly if they are a young, active patient. The MAKO device we use provides leg length restoration accuracy within 3mm.

Patients are also receiving a more bespoke experience – the planning allows implant components to be chosen from the available range, to suit the patient’s individual anatomy.

Simon is sure that these devices will prove invaluable in the training of future surgeons. It has lots of applications in orthopaedics; for example, the accurate 3D models of the bony structure will aid in more accurate planning of bone tumour surgery, meaning surgeons can remove all of the tumour while preserving as much healthy tissue as possible.

After training in Switzerland, Simon has now performed three at The Cromwell Hospital and is discussing it with patients at consultation.

Revision surgery is never a preferred option for patients, so ensuring that the initial surgery is as accurate and bespoke as possible with the assistance of this new technology can only improve patient – and surgeon – satisfaction.