Retrograde Bone Nail With Plate Fixation for Femoral Fractures

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for treating femoral neck fractures, especially those with poor bone quality, often result in non-unions, varus malalignments, and hardware failures due to inadequate fixation stability and stress distribution, particularly in the sub-trochanteric regions where the highest stresses occur.

Innovation Solution

A fracture fixation system comprising a bone plate mounted on the lateral exterior surface of the femur and a retrograde-inserted intramedullary bone nail that avoids the fractured end, providing additional support and stability through angled screws and fixation screws that distribute mechanical loads effectively.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If a proximal lateral femoral plate is used for fixation, then the fracture can be stabilized, but the bone quality adjacent to the fracture site is poor and prone to damage under compression

Engineering Contradiction:
Improvefixation stabilityVSAvoidbone quality adjacent to fracture
Core Design Contradiction:
Stability of the object's compositionVSStrength

Solution Approach 1:

The patent inverts the traditional insertion approach by inserting the bone nail retrograde from the distal end of the femur rather than from the proximal end. This allows the nail to be inserted through intact bone with good quality at the distal end, avoiding the poor quality bone adjacent to the fracture site while still achieving stable fixation of the proximal fracture

Inventive Principle:
Principle #13The other way round (Inversion)

2Duration of action of moving object

If compression is applied to the fracture site to promote healing, then bone healing may be accelerated, but uncontrolled shortening of the femoral head occurs compressing into the trochanteric region

Engineering Contradiction:
Improvebone healing speedVSAvoidfemoral head position
Core Design Contradiction:
Duration of action of moving objectVSShape

Solution Approach 1:

The bone nail acts as an intermediary element that spans the fracture zone and provides controlled compression. The nail's threaded distal portion engages with the intact distal femur, allowing gradual and controlled compression forces to be applied across the fracture site without causing uncontrolled shortening or displacement of the femoral head

Inventive Principle:
Principle #24Intermediary (Mediator)

3Stability of the object's composition

If the bone nail is inserted through the fractured end of the femur, then direct fixation of the fracture can be achieved, but further damage to the fracture or anchoring in weaker bone occurs

Engineering Contradiction:
Improvefracture fixationVSAvoiddamage to fracture site
Core Design Contradiction:
Stability of the object's compositionVSObject-affected harmful factors

Solution Approach 1:

The patent applies retrograde insertion, inverting the traditional approach by inserting the bone nail from the distal end rather than the proximal fractured end. This avoids further damage to the already compromised fracture site and poor quality bone, while still achieving stable fixation through engagement with intact distal bone and appropriate positioning across the fracture

Inventive Principle:
Principle #13The other way round (Inversion)

Data Source

PatentEP4268741A1Retrograde nail with bone plate
Publication Date: 2023.11.01 STRYKER EUROPEAN OPERATIONS LIMITED
  • EP4268741A1 patent drawingFigure 1
  • EP4268741A1 patent drawingFigure 2~3
  • EP4268741A1 patent drawingFigure 4~5

AI summary

A fracture fixation system includes a bone nail configured to be inserted into a canal of a bone by insertion through a distal end of the bone, such that the first end of the bone nail is configured to be seated in a proximal end portion of the bone. The fixation system further includes a bone plate defining an inner surface and an outer surface. The inner surface of the bone plate is configured to abut a lateral surface adjacent the proximal end portion of the bone. The fixation system further includes a first bone screw configured to pass through a first opening defined by the bone plate and a first opening defined by a first portion of the bone nail adjacent the first end of the bone nail to secure the bone plate and the bone nail together.