Is Native Joint Line More Accurately Restored with Robotic Assisted Total Knee Arthroplasty than with Conventional Instruments?

Abstract

Introduction: Changes in joint line (JL) position after total knee arthroplasty (TKA) have revealed implant failure, diminished knee function, and altered knee biomechanics. The purpose of this study was to compare the joint line restoration of robotic-assisted TKA (RA-TKA) and conventional TKA (c-TKA).

Materials and methods: In a prospective cohort study trial, trained fellows performed radiographic analyses on patients receiving RA-TKA (group-1) and c-TKA (group-2) to quantify joint line using the adductor tubercle method. Statistical analysis was used using t-tests, with statistical significance defined as a P < 0.005.

Results: The study contained 150 RA-TKAs and 150 total C-TKAs. Both groups were comparable in demographics such as age, gender, and body mass index. On average, RA-TKAs resulted in a 1.65 ± 0.46 mm shift in the JL position, while C-TKAs resulted in a 2.52 ± 0.52 mm change (P = 0.000). The interclass correlation coefficient between the robotic and conventional groups is around 0.992.

Conclusion: RA-TKA restores the JL position better than C-TKA, which appears to depend on precise planning and ligament balancing, which is attainable with robotic-aided surgery. The clinical relevance of this statistically significant difference requires additional investigation.