Expandable Tip Bone Reshaping Tool for Femoral Head Restoration

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Perthes Disease leads to avascular necrosis of the femoral head, causing bone weakening, deformity, loss of motion, early onset osteoarthritis, and hip pain due to disrupted blood flow and subsequent bone resorption, necessitating a method for restoring anatomical femoral head anatomy.

Innovation Solution

A bone reshaping tool with a hollow tube and expandable tip, featuring bone-engaging drive threads and a tip expander, is used to restore the anatomical shape of the femoral head, accompanied by the introduction of bioresorbable bone cement or graft material to stabilize the restored shape.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the femoral head is left to undergo natural healing after avascular necrosis, then the bone remodeling process occurs, but the head deformity becomes permanent and leads to loss of motion, early onset osteoarthritis, and pain

Engineering Contradiction:

Improveanatomical integrity of femoral headVSAvoidhead deformity and its consequences

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The expandable tip is inserted into the femoral head before the bone deformity becomes permanent, allowing the subchondral bone to be elevated and reshaped during the healing process. This preliminary intervention prevents the development of permanent deformity rather than correcting it after it has set

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The expandable tip acts as an intermediary device that physically supports and elevates the subchondral bone from within the femoral head. This intermediary structure maintains the anatomical geometry of the femoral head during the vulnerable healing period, preventing collapse and deformity

Inventive Principle:

Principle #24Intermediary (Mediator)

2Shape

If a rigid structure is used to restore femoral head anatomy, then anatomical geometry can be maintained, but the device cannot adapt to the curved anatomy of the femoral head

Engineering Contradiction:

Improveanatomical geometry of femoral headVSAvoidadaptation to curved femoral head anatomy

Core Design Contradiction:

ShapeVSAdaptability or versatility

Solution Approach 1:

The expandable tip transitions from a compressed low-profile state during insertion to an expanded state once positioned. This dynamic transformation allows the device to adapt its shape to the curved anatomy of the femoral head while maintaining structural support for anatomical geometry

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The physical parameters of the tip (volume, shape, rigidity) are changed after insertion by expanding the prongs. This parameter change allows the device to conform to the curved femoral head anatomy and provide customized support matching the patient's specific anatomical geometry

Inventive Principle:

Principle #35Parameter changes

3Shape

If the expandable tip is expanded to restore anatomical shape, then the subchondral bone can be elevated to near anatomical geometry, but the expansion mechanism adds device complexity

Engineering Contradiction:

Improvesubchondral bone geometryVSAvoidexpansion mechanism

Core Design Contradiction:

ShapeVSDevice complexity

Solution Approach 1:

The expandable tip uses a nested structure where prongs are contained within a tube during insertion, then deployed outward upon expansion. This nesting approach allows the complex expanded structure to be delivered through a simple catheter-like delivery system, managing device complexity while achieving the desired shape restoration

Inventive Principle:

Principle #7Nested doll (Nesting)

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 solution improves range of motion, reduces the onset of osteoarthritis, and minimizes hip pain by restoring anatomical geometry and promoting revascularization and bone reformation, facilitating shorter recovery times and increased physical activity.

Implementation Method 1

a tip expander disposed at a distal end of the expandable tip, the tip expander disposed to be moved in and out of the expansion tip

Methodology Applied

Scientific EffectMechanical expansion: Mechanical Force

Implementation Method 2

a hollow tube comprising bone-engaging drive threads on at least a portion of an exterior surface of the hollow tube

Methodology Applied

Scientific EffectThread engagement: Screw

Implementation Method 3

the expandable tip connected to a tip orientation knob at a proximal end of the hollow tube to rotatably orient the expandable tip

Methodology Applied

Scientific EffectRotational movement: Mechanical Force

Data Source

PatentUS20240335204A1Bone Reshaping Tool and Method

Publication Date: 2024.10.10 TEXAS SCOTTISH RITE HOSPITAL FOR CHILDREN

AI summary

A bone reshaping tool comprising a hollow tube comprising bone-engaging drive threads on at least a portion of an exterior surface of the hollow tube; an expandable tip at a distal end of the hollow tube, the expandable tip connected to a tip orientation knob at a proximal end of the hollow tube to rotatably orient the expandable tip; and a tip expander disposed at a distal end of the expandable tip, the tip expander disposed to be moved in and out of the expansion tip, and connected to a tip expander drawbar at the proximal end of the hollow tube.