Flexible Spinal Correction Device Using Springs

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current surgical techniques for correcting vertebral column curvature, such as scoliosis, face challenges including large implants that risk infection, potential neurological damage from pedicle screws, limited ability to correct deformity in a short surgery, spinal fusion that prevents movement and growth, and implant breakage.

Innovation Solution

A flexible spinal correction device using springs and fixation members, such as tapes or strings, that apply corrective forces in multiple directions to different segments of the spine, allowing for three-dimensional correction and enabling normal growth and remodeling post-implantation without the need for spinal fusion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If spinal implants and bone fusion are used to correct scoliosis, then deformity correction is achieved, but the risk of infection increases due to large implants

Engineering Contradiction:
Improvedeformity correctionVSAvoidinfection risk
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The spinal column is divided into multiple segments, with implants placed at specific vertebral levels rather than spanning the entire curve. This segmentation reduces the overall implant surface area exposed to potential infection while maintaining corrective capability at critical segments.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention extracts and removes the need for extensive bone fusion by using a flexible rod system that can correct deformity through elastic deformation and gradual remodeling, eliminating the large implant-bone composite structure that creates infection risk.

Inventive Principle:
Principle #2Taking out (Extraction)

2Stability of the object's composition

If pedicle screws are used for anchoring implants, then secure fixation is achieved, but neurological damage risk increases

Engineering Contradiction:
Improvefixation stabilityVSAvoidneurological damage risk
Core Design Contradiction:
Stability of the object's compositionVSObject-affected harmful factors

Solution Approach 1:

The invention introduces an intermediary anchoring system that uses the vertebral body and posterior elements as intermediate structures rather than directly penetrating the pedicle canal. This intermediary approach maintains fixation stability while avoiding direct neural structure violation.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The anchoring mechanism copies the natural attachment points of ligaments and muscles on the vertebral surface, using these existing anatomical landmarks as anchor sites rather than creating new penetration points near neural structures.

Inventive Principle:
Principle #26Copying

3Stability of the object's composition

If spinal fusion is performed to correct deformity, then structural stability is improved, but spinal flexibility and growth are prevented

Engineering Contradiction:
Improvestructural stabilityVSAvoidspinal flexibility
Core Design Contradiction:
Stability of the object's compositionVSAdaptability or versatility

Solution Approach 1:

The invention replaces the static, rigid fusion construct with a dynamic flexible rod system that can adapt to physiological movements and growth. The rod bends and flexes with spinal motion while maintaining corrective alignment, preserving adaptability throughout the growth period.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The flexible rod system allows parameter changes in spinal curvature over time as the patient grows and remodels bone. The implant can be adjusted or replaced as spinal parameters (length, curvature, flexibility) change during development.

Inventive Principle:
Principle #35Parameter changes

4Strength

If rigid implants are used for scoliosis correction, then immediate structural support is provided, but implant breakage occurs due to stiffness

Engineering Contradiction:
Improvestructural supportVSAvoidimplant durability
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The invention uses a flexible rod with optimized cross-sectional geometry that provides sufficient bending stiffness for structural support while maintaining flexibility to accommodate spinal movements. The rod acts as a flexible shell that distributes stresses along its length, preventing stress concentration and breakage.

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 device provides immediate and progressive correction of spinal deformity, maintains spinal flexibility, and allows for continued growth, reducing the risk of implant breakage and neurological damage while minimizing the invasiveness of surgery.

Implementation Method 1

The spring is capable of applying a first force to a first segment and a second force to a second segment

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP3656322B1Adjusting spinal curvature
Publication Date: 2022.11.30 MURRAY
  • EP3656322B1 patent drawingFigure 1~3
  • EP3656322B1 patent drawingFigure 4
  • EP3656322B1 patent drawingFigure 5a~5b

AI summary

Devices for adjusting or correcting the curvature of a vertebral column are described. One such device comprises a spring and at least three fixation members for attaching the spring to the vertebral column in at least three different locations. Another such device comprises a plurality of springs, each spring for attaching to at least two attachment locations of the vertebral column, and at least three fixation members for attaching the plurality of springs to the attachment locations of the vertebral column such that the plurality of springs are attached longitudinally along a length of the vertebral column. A method of adjusting the curvature of a vertebral column is also described.