Lonner JH, et al. - Given the reports indicating encounter to inadvertent soft tissue injury during total knee and hip arthroplasty with autonomous style robotic systems, researchers sought for the incidence of these problems with semiautonomous (ie surgeon-driven) systems. Analysis of a series of 1064 consecutive unicompartmental knee arthroplasties performed using either one of two commercially available semiautonomous robotic systems indicates the safety of current semiautonomous robotic methods, with few complications using meticulous surgical techniques.