New Patient-Outcomes Data Hint at Benefits from Computer-Navigated TKA

Like the vast majority of orthopaedic surgeons, I do not use computer navigation for total knee arthroplasties (TKAs). My hospital does not own the equipment, I have not asked for it, and I feel confident in the outcomes for my patients using current conventional techniques. Moreover, we have not had published data suggesting that using computerized navigation actually improves the one thing we care most about: patient outcomes.  However, the two-year data presented by Petursson et al. in the August 1, 2018 issue of JBJS may represent a tipping point.

The authors report on 2-year results from a double-blind, prospective randomized trial evaluating outcomes in 167 patients following TKAs performed using conventional techniques or computer-guided navigation. Both patients and observing radiologists/physical therapists were blinded to the technique used.

Among the many patient-reported measures used to compare 2-year outcomes, the authors found that scores for 3 subscales favored the computer-navigation group. Specifically, the symptom and sports-and-recreation subscales of the KOOS and the stiffness subscale of the WOMAC showed significantly greater improvements in the group that underwent computer-navigated TKA. These results led Petursson et al. to conclude that TKAs completed with the assistance of computer navigation provided better pain relief and function at two years postoperatively.

These are important findings, as this is one of the largest randomized, double-blind analyses comparing computer navigation versus conventional TKA. While previous studies had found computer navigation to be useful in terms of obtaining neutral mechanical alignment, data showing improved patient outcomes was either lacking or revealed no clinically important between-group differences.  These 2-year data suggest that this is no longer the case.  However, it is important to note that the study does not explicitly state whether patients were still blinded to their treatment at the time when the 2-year follow-up data was collected.  If they were no longer blinded at that point of follow-up, the results would need to be viewed from a more tempered perspective.

Either way, it is important to note that in this study—as in previous research investigating similar questions—TKAs completed using conventional techniques also yielded large improvements in patient-reported outcomes. Still, because patients and surgeons alike continue to be intrigued by the possibilities that technological advances in arthroplasty may offer, studies like this are vital.

Chad A. Krueger, MD
JBJS Deputy Editor for Social Media