Angled Scissor Jack Distractor for Spinal Access
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current surgical methods for treating spinal disorders, such as degenerative disc disease and spondylolisthesis, face challenges in accessing and stabilizing the spine due to anatomical constraints, particularly in the lower lumbar region, where traditional instruments may not adequately address the need for precise distraction and stabilization without compromising vertebral structure.
Innovation Solution
A surgical instrument featuring an angled scissor jack distractor with a sliding pivot bell-crank mechanism allows for off-axis operation, enabling access to disc spaces laterally and avoiding anatomical obstacles, such as the iliac crest, while providing adjustable lordotic tips to accommodate varying spinal curvatures, thereby facilitating procedures like oblique lateral interbody fusion (OLIF) and preserving vertebral structure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If traditional surgical instruments are used to access the lower lumbar spine, then the surgical procedure can be performed, but the instruments cannot adequately access disc spaces laterally due to anatomical constraints such as the iliac crest
Solution Approach 1:
The surgical instrument introduces an off-axis operational dimension by positioning the distractor at an angle relative to the longitudinal axis of the instrument shaft. This angular orientation (typically 30-60 degrees) enables the distal end to access disc spaces laterally and avoid anatomical obstacles such as the iliac crest, while the proximal end remains accessible for manipulation. This dimensional change in instrument orientation resolves the contradiction by providing both adequate access and anatomical adaptability.
Solution Approach 2:
The instrument incorporates adjustable lordotic tips that can be modified to accommodate varying spinal curvatures and patient-specific anatomical variations. The distal end features adjustable angulation capabilities, allowing the instrument to adapt dynamically to different anatomical constraints during the surgical procedure. This dynamic adjustability enables the same instrument to effectively access disc spaces in different lower lumbar levels while accommodating individual anatomical differences.
2Manufacturing precision
If traditional distraction methods are used, then vertebral stabilization can be achieved, but precise control of distraction force and orientation is limited
Solution Approach 1:
The instrument employs a curved or angled shaft design with a bell-crank mechanism that provides mechanical advantage for precise distraction control. The curved geometry of the shaft and the angular orientation of the distractor allow for controlled application of distraction force along the desired vector while maintaining mechanical efficiency. This geometric design enables precise control of distraction orientation without requiring overly complex actuation mechanisms.
Solution Approach 2:
The bell-crank mechanism serves as an intermediary mechanical element that translates linear motion at the proximal end into controlled angular motion at the distal end. This intermediate mechanism provides mechanical advantage and precise control over the distraction force application, allowing the surgeon to control the magnitude and direction of distraction while maintaining a relatively simple overall instrument structure.
3Adaptability or versatility
If lateral access to disc spaces is attempted to avoid the iliac crest, then anatomical obstacles are avoided, but instrument stability and control may be compromised
Solution Approach 1:
The instrument features an asymmetric design with the distractor positioned at an off-axis angle rather than symmetrically aligned with the shaft. This asymmetric angular orientation (typically 30-60 degrees from the longitudinal axis) allows the distal end to access disc spaces laterally and avoid the iliac crest while the proximal end maintains stable handling characteristics. The asymmetric geometry provides both anatomical adaptability and instrument control stability.
Solution Approach 2:
The instrument is segmented into distinct functional sections: a proximal handling section for stable manipulation, a mid-section shaft providing structural support, and a distal section with the angled distractor for precise disc space access. This segmentation allows each section to be optimized for its specific function while working together as an integrated system, maintaining both anatomical adaptability and instrument reliability.
Data Source
AI summary
A surgical instrument comprises a first member defining a longitudinal axis. A second member is connected with a pivot. A third member defines a first axis disposed at an angular orientation relative to the longitudinal axis and is connected with the pivot. The second member is translatable relative to the first member to rotate the pivot to move the third member between a first orientation and a second orientation to space vertebral tissue. Systems and methods are disclosed.