The authors present a technical note for a prone positioning system developed to facilitate cervical extension osteotomy for ankylosing spondylitis in the presence of severe deformity and frailty. Chin-on-chest deformity represents one of the most debilitating changes of ankylosing spondylitis. Where the chin-brow angle approaches or exceeds 90°, prone positioning becomes problematic due to the fixed position of the head. Furthermore, the challenge is compounded where physiological deconditioning leads to frailty, and the side effects of medical therapies decrease muscle mass and skin quality. Conventional prone positioning equipment is not able to cater to all patients. A versatile system was developed using a 3D reconstruction to enable a positioning simulation and verification tool. The tool was used to comprehensively plan the perioperative episode, including spatial orientation and associated equipment. Three-dimensional printing was used to manufacture a bespoke positioning device that precisely matched the contours of the patient, reducing contact pressure and risk of skin injury. The authors were able to safely facilitate surgery for a patient whose deformity and frailty may otherwise have precluded this possibility. The system has potential safety and economic implications that may be of significant utility to other institutions engaging in complex spinal surgery.
Background: In the presence of chin-on-chest deformity of ankylosing spondylitis, positioning for extension osteotomy of the spine is a challenging endeavor. Conventional prone positioning equipment cannot safely accommodate all patients with advanced deformity where the chin brow angle approaches or exceeds 908. Issues such as inability to accommodate the head and associated equipment while providing operative stability and venous congestion of the head represent significant perioperative risks. The sitting position has been advocated as an alternative but is suboptimal for surgical access and anesthetic care. We present a technical note for a positioning system developed to facilitate extension osteotomy in the prone position.Methods: A positioning device was designed to accommodate patients with advanced deformity. A series of patients with chin brow angles of up to 898 were positioned using our new system.Results: We were able to facilitate safe extension osteotomy in the prone position, for procedures lasting up to 14 hours. All our patients were discharged home without significant complication.Conclusions: Our device is simply constructed and may be easily replicated in other institutions engaging in complex spine surgery. We hope our system provides clinicians with greater freedom to provide optimal perioperative care to their patients.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.