Kai-Uwe Lewandrowski1, Lisa Ferrara2, Boyle Cheng3. 1. Center for Advanced Spine Care of Southern Arizona and Surgical Institute of Tucson, Arizona, Department of Orthopaedics, Fundación Universitaria Sanitas, Bogotá, Colombia, Department of Neurosurgery, Universidade Federal do Estado do Rio de Janeiro, Rio de Janeiro, Brazil. 2. OrthoKinetic Technologies LLC, Southport, North Carolina. 3. Carnegie Mellon University, Neurosurgical and Spine Research, Allegheny General Hospital, Pittsburgh, Pennsylvania.
Abstract
BACKGROUND: Expandable cages have gone through several iterations since they first appeared on the market in the early 2000s. Their development was prompted by some common problems associated with static interbody cages, including migration, expulsion, dural or neural traction injury, and pseudarthrosis. OBJECTIVE: To summarize current technological advances from earlier expandable lumbar interbody fusion devices to implants with vertical and medial-to-lateral expansion mechanisms. METHODS: The authors review the currently available expandable cage designs, the incremental technological advances, and how these devices impact minimally invasive surgery interbody procedures and clinical outcomes. The strategic concepts intended to improve the minimally invasive application of expandable interbody fusion implants are reviewed from a surgeon's perspective in a clinical context to discuss how their use may improve patient outcomes. CONCLUSIONS: The geometrical configuration, effective stiffness of composite multi-material cage designs may impact the bone-implant contact area with the endplates. Hybridization strategies of expandable cage technology with modern minimally invasive and endoscopic spinal surgery techniques are presented by outlining their advantages and disadvantages. LEVEL OF EVIDENCE: 1 CLINICAL RELEVANCE: Systematic review. This manuscript is generously published free of charge by ISASS, the International Society for the Advancement of Spine Surgery.
BACKGROUND: Expandable cages have gone through several iterations since they first appeared on the market in the early 2000s. Their development was prompted by some common problems associated with static interbody cages, including migration, expulsion, dural or neural traction injury, and pseudarthrosis. OBJECTIVE: To summarize current technological advances from earlier expandable lumbar interbody fusion devices to implants with vertical and medial-to-lateral expansion mechanisms. METHODS: The authors review the currently available expandable cage designs, the incremental technological advances, and how these devices impact minimally invasive surgery interbody procedures and clinical outcomes. The strategic concepts intended to improve the minimally invasive application of expandable interbody fusion implants are reviewed from a surgeon's perspective in a clinical context to discuss how their use may improve patient outcomes. CONCLUSIONS: The geometrical configuration, effective stiffness of composite multi-material cage designs may impact the bone-implant contact area with the endplates. Hybridization strategies of expandable cage technology with modern minimally invasive and endoscopic spinal surgery techniques are presented by outlining their advantages and disadvantages. LEVEL OF EVIDENCE: 1 CLINICAL RELEVANCE: Systematic review. This manuscript is generously published free of charge by ISASS, the International Society for the Advancement of Spine Surgery.
Authors: Mohammed Ali Alvi; Shyam J Kurian; Waseem Wahood; Anshit Goyal; Benjamin D Elder; Mohamad Bydon Journal: World Neurosurg Date: 2019-04-05 Impact factor: 2.104
Authors: Ammar H Hawasli; Jawad M Khalifeh; Ajay Chatrath; Chester K Yarbrough; Wilson Z Ray Journal: Neurosurg Focus Date: 2017-08 Impact factor: 4.047
Authors: Jeffrey D Coe; James F Zucherman; Donald W Kucharzyk; Kornelis A Poelstra; Larry E Miller; Sandeep Kunwar Journal: Med Devices (Auckl) Date: 2016-09-28