Friday, March 3, 2017

Arthroplasty - finding our way, what tools are of value?

Navigation and Robotics in Knee Arthroplasty

These authors reviewed the available literature on the use of navigational aids in total knee arthroplasty - a procedure in which the desired anatomic alignment can be precisely defined and accurately measured. 

They note that computer-assisted surgery for total knee arthroplasty can be performed with use of computer-assisted navigation, handheld navigation, partially or fully robot-assisted technology, and patient-specific instrumentation.

The evidence suggests that computer-assisted navigation leads to improved component alignment and a reduction in the likelihood of mechanical axis outliers after total knee arthroplasty, however it is not known whether these differences have any long-term benefit on clinical or functional outcomes.

Robot-assisted surgery
 has not been extensively studied in the context of unicompartmental and total knee arthroplasty, and, although initial reports have been promising in terms of accuracy and precision, this method is associated with substantial cost and a steep learning curve.

Patient-specific instrumentation

was designed to overcome many of the intraoperative challenges associated with navigation or robotic surgery, but early reports have demonstrated only minor improvements in surgical accuracy, and no change in outcomes, compared with conventional total knee arthroplasty.

Comment: These authors offer this commentary on their findings: "At the present time, most of these technologies are too costly to justify their routine use in place of conventional TKA. Nonetheless, much of  the marketing for these technologies tends to emphasize unsubstantiated benefits while disregarding potential drawbacks. As the health-care environment becomes increasingly competitive, hospitals may embrace these technologies to attract patients. It is the role of the surgeon to explain the benefits and drawbacks of these technologies to patients so that they can make informed decisions regarding surgery. Before these technologies are embraced, future studies must demonstrate improved clinical outcomes combined with affordable costs."

We should also ask, even if these technologies are shown to be of clinical benefit, on which cases should they be used and which surgeons and medical centers should use them?

While analogous technologies are advocated for the shoulder, we should pay attending to the data from our knee surgeon colleagues who have a much greater volume of cases/year and clearer measures of the anatomic and clinical outcome.