PurposeInnovative technologies such as robotic assistance and intraoperative load sensors for total knee arthroplasty (TKA) aim to reduce outliers, as well as to address patient dissatisfaction. There is currently no information available that assesses the findings of using these technologies together during TKA.MethodsIntraoperative data on alignment, gap spacing, and quantitative balance was prospectively collected in a cohort of 79 consecutive TKAs performed with robotic assistance. An instrumented trial component was utilized that captured medial and lateral tibio-femoral loads, allowing the quantitative assessment balance.ResultsOf the 79 knees, 58 (73%) had varus alignment and 21 (37%) had valgus. We divided these groups into correctable and fixed deformities. Correctable varus knees: At trial reduction 30% of the knees demonstrated quantitative imbalance at trial reduction. Fixed varus knees. At trial reduction 55% (of knees were deemed imbalanced. Correctable valgus knees: At trial reduction, 35% were imbalanced. Fixed valgus knees: Half of the knees (n=2) were imbalanced at trial reduction. The imbalance in all groups was addressed with combinations of bone and soft tissue adjustments so that at final implantation 99% of cases (n=78) were quantitatively balancedConclusionWhile the robot was both precise and accurate with its cuts to create appropriate gap spaces, only 57% were quantitatively balanced. Ultimately, almost all knees were balanced with final implants, but that state required the use of additional techniques, including soft tissue and bony modifications. More data is needed to determine if these technologies will equate to increased clinical success.
What is a balanced knee replacement?
