Robotic-assisted baseplate preparation in primary reverse total shoulder arthroplasty: surgical technique and contemporary review

During primary reverse total shoulder arthroplasty, accurate glenoid component placement remains one of the most challenging aspects of this surgery. As such, there has been a recent evolution of both preoperative and intraoperative modalities to assist with planning and executing component placement. Robotic assistance is now approved by the United States Food and Drug Administration through either the ROSA or MAKO platforms. The authors have gained some preliminary experience with the MAKO robotic system, consisting of a robotic arm, camera system, and console. Use of this robot involves insertion of a fiducial marker or checkpoint and use of arrays with reflective discs on the coracoid, probe, robotic arm, and robotic registration array. After registration, the robotic arm effector end is used to sculpt bone for the baseplate, including preparation for central post or central screw fixation. At present time, the MAKO robotic arm can only be used for implantation of a primary reverse baseplate, with no features allowing anatomic glenoid implantation, humeral preparation, motion or soft tissue assessment, or revision surgery. Although reproducible accuracy and precision have been demonstrated relative to manual preparation and patient-specific instrumentation, substantial barriers to adoption include limited features, cost, surgical learning curve, additional operating room time, and little clinical outcome data.