ABSTRACT
After several years of product development, animal trials and human cadaver testing, the SpineAssist--a miniature bone-mounted robotic system--has recently entered clinical use. To the best of the authors' knowledge, this is the only available image-based mechanical guidance system that enables pedicle screw insertion with an overall accuracy in the range of 1 mm in both open and minimally invasive procedures. In this paper, we describe the development and clinical trial process that has brought the SpineAssist to its current state, with an emphasis on the various difficulties encountered along the way and the corresponding solutions. All aspects of product development are discussed, including mechanical design, CT-to-fluoroscopy image registration, and surgical techniques. Finally, we describe a series of preclinical trials with human cadavers, as well as clinical use, which verify the system's accuracy and efficacy.
Subject(s)
Robotics , Spinal Fusion/methods , Surgery, Computer-Assisted , Animals , Biomedical Engineering , Bone Screws , Cadaver , Equipment Design , Fluoroscopy , Humans , Image Processing, Computer-Assisted/methods , Miniaturization , Minimally Invasive Surgical Procedures , Models, Animal , Patient Care Planning , Spinal Diseases/surgery , Spinal Fusion/instrumentation , Spine/surgery , Tomography, X-Ray ComputedABSTRACT
BACKGROUND: Spinal fusion is a commonly performed procedure for a variety of conditions. Pedicle screw fixation has become the standard of care for stabilization of the thoracic and lumbar spine. Precise screw placement is essential to avoid injury to adjacent neural structures. Patients with severe deformity or prior surgery present a challenge to the accurate placement of pedicle screws. Additionally, minimally invasive and percutaneous surgical techniques also present a greater challenge to accurate screw placement and require heavier reliance on intraoperative fluoroscopic imaging, which presents an occupational hazard for the surgeon and the operating-room (OR) staff. The purpose of this paper is to introduce the SpineAssist, a miniature robotic guidance system, developed to assist spine surgeons in the accurate placement of pedicle screws. METHODS: The operative technique is described, as is the experience and results with 14 patients during a 6 month period during which this system was used. RESULTS: The SpineAssist performed successfully in 93% of the cases in which it was used. 96% of the screws placed were determined to be within 1 mm of their planned trajectory. CONCLUSIONS: Difficulties encountered with use of the SpineAssist, while minimal, will be described and suggestions made for future improvements.