Mako robot-assisted total hip replacement

Modern hip replacement surgery was pioneered by Sir John Charnley in the UK in the early 1960s. The procedure and implant used were developed and refined over the next 30 years to a degree that the hip replacement was named ‘the Operation of the 20th Century’ given that it relived hip pain and allowed patients to return to a more active lifestyle.

Over the past 20 years, surgeons and industry have fine-tuned not only the implants but also the bearings used so hip replacement surgery can even be considered in younger patients.

Whilst there has been some development in the operative technique, such as less invasive and soft tissue sparing approaches allowing patients to be safely discharged within 2 or 3 days, what has not really improved is the accuracy that the surgeons can implant the hip replacement. To date, it has still been down to “experience and eyeballing the position and alignment” during the operation. Getting this right has a major influence not only on achieving equal leg lengths but also on optimising muscle function and reducing post-operative limping.

In trying to find the best outcome for themselves the patient’s only option was to find a well-trained and experienced specialist hip surgeon often following a recommendation by their GP or by a friend or colleague.

Whilst choosing a specialist hip surgeon is still essential for achieving the desired outcome following a hip replacement, given that we live in an age of technology and everyone of all ages relies on the internet and trusts computer technology on a daily basis, surely using a computer to help plan and a robot to assist in executing the surgery will aid even the most experienced specialist hip surgeon to be more accurate with regard to both implant positioning and alignment?

Robotic-assisted surgery was developed in the United States by Mako Surgical in 2006. Stryker, one of the largest Orthopaedic implant companies in the world, saw the potential of this technology and purchased Mako in 2013.  Stryker announced in early 2015 it had been granted FDA-approval for its robotic hip and knee replacements.

In essence, Mako is a surgical assistance system combining a robotic arm and a computer allowing the surgeon to be even more precise at the time of the operation. The surgeon is always ‘in control’ of the robotic arm manoeuvring it himself but utilizing feedback from the robotic arm to the computer to be more accurate with regard to implant placement and alignment.

Mr Burwell visited Stryker’s headquarters outside New York in September 2016 to witness the Mako robotic-arm assisted technology first hand. In December 2017 Mr Burwell attended surgery in Exeter with Professor John Timperley, where the first Mako robot in the UK was sited.  Mr Burwell became a ‘Mako certified’ hip replacement specialist by Stryker in November 2018 and Circle Bath introduced Mako robotic-arm assisted hip replacements in February 2019.

What is the difference between a ‘standard’ hip replacement and a Mako robotic-arm assisted hip replacement? Surgeons have been using 2-D digital x-rays for the past decade to plan surgery. Mako requires a pre-operative CT scan which allows for patient-specific 3-D digital planning, which is far more accurate than 2-D planning. During the operation, the Mako computer and robotic arm allow the surgeon to place implants with much greater precision and to reduce any variability. There are already numerous research articles in the Orthopaedic literature that demonstrate improved accuracy of component position1, improved patient-reported outcomes2, demonstrates favourable short-term outcomes and does not result in higher complication rates compared to non-robotic THA3.

What has yet to be confirmed is whether improved accuracy at the time of surgery will result in improved clinical outcomes in the longer term.

When considering having a hip replacement the most important decision for the patient to make is still which surgeon to see and then ideally going on to develop a good rapport between the patient and surgeon.  Mr Burwell has been an Orthopaedic Consultant in Bath for almost 20 years and has sub-specialised limiting his practice solely to hip replacement surgery since 2011 and undertakes 300+ hip replacements every year. Robotic-assisted surgery appears to have ‘come of age’ with the development of the Mako system. The technology was developed in 2006 and the first Mako robotic-assisted hip replacement was in October 2010. Mako has been more widely available in the USA since 2015 and has proven to be a safe technology with over 600 Mako robots in use worldwide. This is a very exciting development and Mr Burwell is delighted to now be able to offer Mako robotic-assisted hip replacements to his patients at Circle Bath with the aim to not only relieve the pain of hip arthritis but also to enhance their rehabilitation and optimise their outcome following hip replacement surgery.


1    Comparison of Robotic-assisted and Conventional Acetabular Cup Placement in THA: A Matched-Pair Controlled Study

DombBG, El BitarYF, SadikBS, Stake CE, BotserIB

ClinOrthopRelatRes; 2014 , Vol 472: 329-36

2   Improved Functional Outcomes with Robotic Compared with Manual Total Hip Arthroplasty

Bukowski BR, Anderson P, KhlopasA, ChughtaiM, Mont MA, IllgenRL

Surgical Technology International XXIX; Orthopaedic Surgery; Sept 2016

3 Robotic-Arm Assisted Total Hip Arthroplasty – Clinical Outcomes and Complication Rate

ItayPerets, John P. Walsh, Mary R. Close, Brian Mu, Leslie Yuen, Benjamin G. Domb.

IntJ Med Robotics ComputAssist Surg. 2018;14:e1912.