Reproducibility is a critical part of total knee arthroplasty. One option that may optimize this trait is MAKO. Commonly referred to as robotic augmentation, Mako is used primarily in total knee and to a lesser extent, total hip replacement surgery. The estimated price of approximately 1 million dollars would put a dent in any capital budget, but could it be worth it?
Medgadget describes how the Imperial College London paved the way for MAKO in 2002 with a device they called Acrobat or Active Constraint Robot.  The device changed design and ownership a few times over the next decade finally landing at Stryker in the form of what we know today as MAKO. Throughout all the changes MAKO kept its core concept of Active Constraint, allowing the optimization of consistent, accurate and reproductive surgery.
The top half of the ATM-sized device is made up of a robotic arm that can hold a variety of cutting tools. Placement of the tool is designed for easy grip, guidance and activation by the surgeon. MAKO uses Active Constraint by sending auditory or tactile feedback through its arm to constrain the cutting area within a boundary. That boundary is predefined by the computer and the surgeon based on 3D imaging collected preoperatively.  MAKO’s movement constraint still provides the surgeon with ultimate control overcutting. It’s easy to generalize and feel that a guide or jig is performing the same function, but Dr. Bob Thomas points out that a key advantage of MAKO is that it provides a much more ergonomic experience. It handles much of the extraneous effort by relieving the stress and fatigue associated with having to contort into cramped positions required of other replacement surgical methodologies. 
Active Constraint sounds great, but how does it know where the boundary is? In MAKO’s case, special pins fitted with reflector disc arrays are attached to specific parts of the patient. A special Infrared (IR) camera reader across the room can recognize those discs and will feed the information through the computer to the robotic arm providing spatial awareness of both the patient and cutting tool at all times.
With the extra cameras, arrays and computers together with the sheer size of the MAKO system, it’s not difficult to understand where the price tag comes into play. However, the large capital investment remains a significant barrier. While the overall demand for total knee arthroplasty continues to rise, the reimbursement contributes to decrease. This creates an economic pressure point for hospitals and ASCs. The MAKO system typically will require organizations to accept a single vendor contract, which may lead to undesirable implant prices.The MAKO system provides a mechanism to attract patients in the increasingly competitive marketplace of total knee arthroplasty. Unfortunately, the large capital investment and restriction involving implant vendors make this a strategic deduction for each practice and hospital. It will be important to continue to track the long term patient reported outcomes to see if Mako does truly render better outcomes, which would help to justify the cost.
- Editors, M. (2006, February 9). The Acrobot® Surgical System | Retrieved from https://www.medgadget.com/2006/02/the_acrobot_sur.html
- Waddell, B. S., Carroll, K., & Jerabek, S. (2017, July 7). Technology in Arthroplasty: Are We Improving Value? Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5577416/
- Thomas, B., & Panorama Orthopedics & Spine Center. (2018, October 31). Retrieved from https://www.youtube.com/watch?v=FiLf4KGd494