Conventional versus Smart Wireless Navigation in Total Knee Replacement: Similar Outcomes in a Randomized Prospective Study

Abstract

Purpose The development of new computer-assisted navigation technologies in total knee arthroplasty (TKA) has attracted great interest; however, the debate remains open as to the real reliability of these systems. We compared conventional TKA with last generation computer-navigated TKA to find out if navigation can reach better radiographic and clinical outcomes. Methods Twenty patients with tricompartmental knee osteoarthritis were prospectively selected for conventional TKA ( n = 10) or last generation computer-navigated TKA ( n = 10). Data regarding age, gender, operated side, and previous surgery were collected. All 20 patients received the same cemented posterior-stabilized TKA. The same surgical instrumentation, including alignment and cutting guides, was used for both the techniques. A single radiologist assessed mechanical alignment and tibial slope before and after surgery. A single orthopaedic surgeon performed clinical evaluation at 1 year after the surgery. Wilcoxon's test was used to compare the outcomes of the two groups. Statistical significance was set at p < 0.05. Results No significant differences in mechanical axis or tibial slope was found between the two groups. The clinical outcome was equally good with both techniques. At a mean follow-up of 15.5 months (range, 13–25 months), all patients from both groups were generally satisfied with a full return to daily activities and without a significance difference between them. Conclusion Our data showed that clinical and radiological outcomes of TKA were not improved by the use of computer-assisted instruments, and that the elevated costs of the system are not warranted. Level of Evidence This is a Level II, randomized clinical trial.

Comparison of iASSIST Navigation System with Conventional Techniques in Total Knee Arthroplasty: A Systematic Review and Meta‐Analysis of Radiographic and Clinical Outcomes

“…After reading full texts, 19 studies were excluded according to eligibility criteria. Finally, 8 studies were included in this review, of which 6 studies were in English and 2 in Chinese language.…”

“…The NOS score of included studies ranged from 6 to 9, with an average score of 7.12. A total of 5 studies were high quality, and the other 3 were moderate quality studies.…”

“…The iASSIST (Zimmer, Warsaw, IN, US) navigation device is a handheld computer‐assisted accelerometer‐based stereotaxic system that simplifies the registration process. The iASSIST system is validated in cadavers and clinical studies by Scuderi et al ,.…”

“…In the past 3 years, studies on the iASSIST system have gradually increased in number, with some researchers believing that it may improve the accuracy of lower limb alignment, although some have found no significant difference between the iASSIST and conventional techniques. The purpose of this meta‐analysis is to determine whether the iASSIST navigation system contributes to more accurate lower limb alignment, improving postoperative functional outcome, compared with conventional surgical techniques.…”

Pros and cons of navigated versus conventional total knee arthroplasty—a retrospective analysis of over 2400 patients

“…Since then, the use of imageless navigation systems has been discussed among experts [ 10 – 16 ]. Although some authors did not find any differences in postoperative radiological and clinical parameters between navigated and conventional TKA [ 10 – 12 ], other authors found improvements in leg alignment and even in functional results after the use of navigation systems [ 13 – 15 ]. Imageless navigation requires longer surgery durations [ 14 , 17 , 18 ], partly because of the necessary insertion of Schanz screws to fix the reference arrays for optical navigation.…”