Does not compute: Knee replacement not helped by computer navigation

Despite being touted as an improvement to conventional knee replacement procedures, computer-assisted navigation provided no advantage over the traditional surgical procedure, according to a study published in the Nov. 21 edition of The Journal of Bone and Joint Surgery.

Authors Young-Hoo Kim, MD, and colleagues from the Ewha Womans University School of Medicine in Seoul, Korea, found no improvement in knee function, alignment or durability when using computer navigation to aid total knee arthroplasty (TKA) procedures.

The findings were based on a prospective study which compared the results of 520 patients with osteoarthritis who underwent computer-navigated TKA for one knee and conventional TKA for the other knee. Patients were assessed before surgery, three months post-surgery, one year post-surgery and annually thereafter for a mean follow-up of 10.8 years.

There were no statistically significant differences in knee function scores, pain scores or scores using the Western Ontario and McMaster Universities Osteoarthritis Index, according to the study results. Survivorship of the implants at final follow-up was 98.8 percent in the computer-navigated TKA group and 99.2 percent in the conventional TKA group, a difference that was not statistically significant.

One of the few differences between techniques was procedure time. Both the mean operative time and time during which the surgeons use a tourniquet were significantly longer in the computer-navigated TKA group than the conventional group.

Kim and colleagues acknowledged that previous research has found computer navigation improved positioning of components, but said their study did not demonstrate difference in rotational alignment between the procedure types.

“In our study, the effect of computer-navigated total knee arthroplasty compared with conventional total knee arthroplasty on long-term implant survival remains unproven,” wrote the authors.