No difference in clinical outcomes between portable navigation and conventional instrumentation in total knee...

Portable accelerometer-based navigation devices (PAD) in total knee arthroplasty (TKA) have been proposed to combine the alignment precision of computer navigation with the efficiency of conventional instrumentation (CON). The aim of this study was to determine if PAD was more effective than CON in TKA in improving clinical outcomes at medium term follow-up.

Participants undergoing primary TKA were randomly assigned to either PAD or CON. The primary outcome was the mean between-group difference in the four subscales of the Knee injury and Osteoarthritis Outcome Score (∆KOOS₄ ) between preoperative status and latest follow-up. Secondary outcomes included analysis of between-group differences in all KOOS subscales, Western Ontario and McMaster Universities Osteoarthritis Index (∆WOMAC) scores, complications and reoperation rates.

Of the 178 participants allocated to a treatment arm, 159 (89.3%) completed follow-up at a mean of 4.3 years (range 3.2-5.8 years). There was no statistically significant or clinically meaningful difference in ∆KOOS₄ between preoperative status and latest follow-up (PAD = 41, CON = 43; p = 0.5). There was no difference in mean ∆WOMAC scores (PAD = 39, CON = 41; p = 0.9) or ∆KOOS subscales between groups. In addition, there were no differences in complications or reoperations between groups.

PAD was not superior to CON in improving patient-reported outcomes or reducing complications and reoperation rates at medium term follow-up. The use of PAD in TKA to improve clinical outcomes alone cannot be justified based on the results of this study.