Bilateral Total Knee Arthroplasties Performed With and Without Computer Navigation: Prospective 11-Year Postoperative Evaluation

Abstract

Background: Computer navigation has been used in total knee arthroplasty in an attempt to improve component alignment and clinical outcomes, although few studies directly compare computer navigation to traditional instrumentation in the same patient.

Methods: Bilateral total knee arthroplasties performed during the same surgical intervention utilizing computer navigation in one knee and traditional instrumentation in the contralateral knee were prospectively collected and followed. Reoperations and adverse events were documented. Statistical analyses were performed between the two groups to determine differences in clinical outcomes.

Results: There were 79 patients who had a mean follow-up of 11.8 years (range, five to 16). When comparing computer navigation to traditional instrumentation cohorts, mean postoperative femoral component coronal angle (94.9 versus 94.9°, P = 0.88), femoral component flexion (2.1 versus 1.8°, P = 0.53), tibial component coronal angle (89.7 versus 90°, P = 0.24), and posterior tibial slope (2.4 versus 2.9°, P = 0.15) showed no statistical differences. Computer navigation demonstrated a decrease in posterior tibial slope outliers (1 versus 8, P = 0.018) compared to traditional instrumentation, but no differences in the other component angles. Clinically, there were no differences in mean postoperative extension (0.2 versus 0.2°, P = 0.97), flexion (127.3 versus 127.1°, P = 0.85), functional Knee Society Scores (91.3 versus 90.5, P = 0.77), reoperation rate (6.3 versus 2.5%, P = 0.44), or closed manipulation rate (2.5 versus 3.8%, P = 0.65) at final follow-up comparing computer navigation to traditional instrumentation, respectively. Computer navigation reoperation indications included two patellar osteolysis, one infection, one patellar clunk syndrome, and one symptomatic arthrotomy nonabsorbent suture removal. Traditional instrumentation reoperation indications included one infection and one arthrotomy dehiscence.

Conclusions: Computer navigation reduced posterior tibial slope outliers, although this did not translate to any appreciable difference in clinical outcome at 11 years' mean follow-up in the hands of a fellowship-trained total joint specialist.

Keywords: bilateral; clinical outcomes; computer navigation; radiographic alignment; total knee arthroplasty.