Interspinous Spacer With Leaf Spring and Wire Straps

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Spinal stenosis treatment methods face challenges in maintaining spinal stability, particularly in dynamic stenosis, where distraction is required, and in hard stenosis, where tissue removal compromises stability, leading to potential loss of spinal stability.

Innovation Solution

An interspinous spacer with a W-shaped or S-shaped leaf spring design, incorporating wire straps or hooks for attachment, allowing for distractive and compressive forces, and made from biocompatible materials like titanium or PEEK, to enhance spinal stability and facilitate safer attachment between adjacent vertebrae.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If tissue removal is performed to treat hard spinal stenosis, then the spinal canal or foramina obstruction is relieved, but spinal stability is compromised

Engineering Contradiction:
Improvespinal canal obstructionVSAvoidspinal stability
Core Design Contradiction:
Object-affected harmful factorsVSStability of the object's composition

Solution Approach 1:

An interspinous spacer is introduced as an intermediary device between the adjacent spinous processes to maintain spinal stability after tissue removal. The spacer acts as a mediator that prevents excessive motion and maintains proper spacing, compensating for the stability loss caused by decompression surgery.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The spacer's physical parameters (stiffness, height, material properties) are specifically designed and adjusted to match the patient's anatomical requirements and the extent of tissue removal. This allows optimization of stability maintenance while accommodating the altered spinal geometry after decompression.

Inventive Principle:
Principle #35Parameter changes

2Volume of stationary object

If distraction is applied to treat dynamic spinal stenosis, then the spinal canal space is increased, but spinal stability may be compromised

Engineering Contradiction:
Improvespinal canal spaceVSAvoidspinal stability
Core Design Contradiction:
Volume of stationary objectVSStability of the object's composition

Solution Approach 1:

The spacer incorporates dynamic characteristics that allow it to adapt to physiological spinal motions. The device can flex and adjust during normal spinal movement while maintaining adequate distraction to prevent stenosis, thereby preserving both spinal canal space and natural spinal dynamics.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The spacer's mechanical parameters are designed to provide appropriate distraction forces while allowing controlled motion. The stiffness and elasticity parameters are tuned to maintain spinal canal space during flexion-extension movements without causing excessive instability.

Inventive Principle:
Principle #35Parameter changes

3Stability of the object's composition

If an interspinous spacer is inserted to increase spinal stability, then segmental stiffness is improved, but device complexity increases

Engineering Contradiction:
Improvesegmental stiffnessVSAvoidspacer structure
Core Design Contradiction:
Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The spacer is designed as a segmented or modular structure that can be inserted and positioned between spinous processes. This segmentation allows for simpler individual components that collectively provide the required stability, reducing the complexity of each individual element while achieving the overall stability goal.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The spacer utilizes flexible material structures that can conform to the natural anatomy of the spinous processes. This flexibility reduces the need for complex rigid structures, allowing the device to achieve stability through material properties and geometric design rather than mechanical complexity.

Inventive Principle:
Principle #30Flexible shells and thin films

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The spacer provides consistent force transmission and improved spinal stability by allowing adjustable stiffness, reducing bone damage, and enabling faster, simpler, and safer implantation, while accommodating anatomical variations.

Implementation Method 1

an elastically flexible central portion for enabling compression and/or extension of the spacer

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP2197374B1Interspinous spacer
Publication Date: 2018.10.31 SYNTHES GMBH
  • EP2197374B1 patent drawingFigure 1
  • EP2197374B1 patent drawingFigure 2
  • EP2197374B1 patent drawingFigure 3

AI summary

The present invention relates to an interspinous spacer (10, 10', 10' ', 10' ' ', 10"", 10' " ") for implantation between adjacent spinous process (SP) to treat spinal stenosis. The interspinous spacer preferably includes a W-shaped or S-sha?ed leaf spring body member (21) for insertion between adjacent spinous processes and one or more wire straps (42) extending from the body to attach the spacer to the adjacent spinous processes. The wire straps are preferably sized and configured to extend from one side of the leaf spring, along one side of a spinous process, over or under the spinous process to the other side wherein the wire strap can be coupled to the leaf spring. Alternatively, the spacer may include one or more hooks (60) for engaging one or both of the adjacent spinous processes. Preferably, the top bone contacting surface (22) has a more accentuated convex shape compared to the bottom surface (24) so that the spacer is better able to sit in the naturally formed concavity present in the bottom surface of a spinous process.