Expandable Intervertebral Spacer With Cam-Frame Height Adjustment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The stability of the vertebral column is compromised due to factors such as normal physiological aging, mechanical injury, and disease, leading to impairment or loss of disc function, which necessitates additional support between adjacent vertebrae.
Innovation Solution
An adjustable intervertebral spacer with endplates and an actuation subassembly, including a drive nut, drive screw, and cam frame, allows for expansion between vertebrae by translating the cam frame along a longitudinal axis, engaging cams to increase the spacer's height.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a fixed-height spacer is inserted between adjacent vertebrae, then the spacer provides structural support, but it cannot adapt to varying anatomical requirements or correct different degrees of spinal deformity
Solution Approach 1:
The spacer incorporates an expandable structure that transitions from a compressed delivery configuration to an expanded deployed configuration. The expandable cage body includes multiple struts that can change in length or angle, allowing the spacer to adapt its height and shape to match the specific anatomical requirements of different patients and spinal conditions, while maintaining a relatively simple initial implantation procedure
Solution Approach 2:
The expandable spacer is designed to be nested within itself or within the delivery device during storage and implantation. The cage struts and endplates are configured to fold or compress into a compact form that fits within the delivery system, then expand to the desired configuration after implantation, reducing the complexity of the delivery procedure while providing adaptability
2Manufacturing precision
If a traditional non-adjustable spacer is used, then the implantation procedure is simpler, but the spacer cannot be adjusted to achieve optimal spinal alignment and disc height restoration
Solution Approach 1:
The spacer includes adjustable struts with varying lengths or angles that can be configured during implantation to achieve precise spinal alignment. The expandable structure allows surgeons to fine-tune the spacer's geometry to restore optimal disc height and vertebral alignment, improving manufacturing precision without requiring completely complex implantation procedures
Solution Approach 2:
The spacer is pre-configured with adjustable components and mechanisms that allow for precise alignment adjustments to be made during the implantation procedure. The design includes pre-formed struts and endplates that can be positioned and locked into specific configurations, enabling surgeons to achieve optimal spinal alignment while maintaining procedural simplicity through pre-planned adjustment options
3Adaptability or versatility
If the spacer structure is made more complex to provide adjustability, then it can accommodate various spinal conditions, but the risk of intraoperative complications and device failure increases
Solution Approach 1:
The expandable spacer uses a controlled expansion mechanism with interlocking struts and joints that maintain structural integrity during and after expansion. The dynamic structure allows adaptation to various spinal conditions while incorporating features like locking mechanisms and load-bearing designs that ensure reliability and reduce the risk of intraoperative complications or device failure
Solution Approach 2:
The spacer design includes built-in features such as load-distributing endplates, reinforced struts, and controlled expansion mechanisms that prevent structural failure during implantation and use. These preemptive design elements cushion against potential complications by ensuring the device can withstand various loading conditions and anatomical variations without failing
4Object-affected harmful factors
If a minimally invasive approach is used for spacer implantation, then patient trauma is reduced, but the precision of spacer placement and expansion control is compromised
Solution Approach 1:
The spacer is designed to be delivered through a minimally invasive approach by nesting the expandable structure within a delivery device. The compressed spacer fits through small incisions and is then deployed and expanded to the desired configuration at the target site, reducing patient trauma while maintaining placement precision through the guidance and control provided by the delivery system
Data Source
AI summary
A spacer for separating bones of a joint, the spacer includes a first endplate configured to engage a first bone of the joint; a second endplate configured to engage a second bone of the joint; and an actuation subassembly comprising a drive nut, a drive screw coupled to the drive nut, and a cam frame coupled to the drive screw, wherein the cam frame is disposed between the first endplate and the second endplate, wherein the cam frame comprises a proximal frame end, a distal frame end, and lateral frame sides, wherein cams disposed on the lateral frame sides selectively engage at least one of the first endplate or the second endplate.