Orthopedic Joint Flexion Moment Holding Device

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional orthopedic joint devices, such as prosthetic knee joints, lack the ability to securely unlock and adapt to varying usage conditions, particularly failing to provide adjustable damping during different phases of movement, which limits their functionality and safety for users with limited mobility.

Innovation Solution

An orthopedic joint device with a flexion moment-controlled holding device, incorporating magnetic coupling, suction cup, snap spring, or hydraulic locking units, and a separate damper system that allows adjustable damping resistance, enabling secure locking and flexible unlocking based on applied forces, thereby facilitating safe and adaptive movement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a conventional positive locking device is used to secure the upper part relative to the lower part, then locking reliability is improved, but the ability to unlock and adapt to varying usage conditions deteriorates

Engineering Contradiction:
Improvelocking reliabilityVSAvoidability to unlock and adapt
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent applies a dynamic holding device that transitions between locked and unlocked states based on applied flexion moments. The holding force is not fixed but adapts dynamically - maintaining strong locking during normal activities (standing, walking) and automatically releasing when a predetermined flexion moment is exceeded, enabling the joint to adapt to varying usage conditions without manual intervention

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The invention changes the holding parameter from a fixed positive lock to a variable holding force that responds to mechanical stimuli. The holding device adjusts its locking strength based on the applied flexion moment, transitioning from a high holding force state during normal use to an unlocked state when the moment threshold is reached, thereby resolving the contradiction between reliable locking and adaptive unlocking

Inventive Principle:
Principle #35Parameter changes

2Stability of the object's composition

If manual operation of a release mechanism is required to unlock the prosthetic knee joint, then locking stability is improved, but ease of operation deteriorates

Engineering Contradiction:
Improvelocking stabilityVSAvoidease of unlocking
Core Design Contradiction:
Stability of the object's compositionVSEase of operation

Solution Approach 1:

The holding device is designed to unlock automatically in response to a flexion moment being applied to the joint. When the user needs to flex the knee (e.g., to sit down), the natural application of flexion moment directly triggers the release mechanism, eliminating the need for separate manual operation. The system serves itself by using the user's own movement intention to initiate unlocking

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent replaces complex manual release mechanisms with a simpler mechanical response system. Instead of requiring the user to operate buttons, levers, or switches, the holding device responds directly to the mechanical stimulus of applied flexion moment, substituting electronic or complex mechanical release systems with a straightforward moment-responsive mechanism

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Device complexity

If adjustable damping during swing or stance phases is not provided, then device complexity is reduced, but adaptability to different movement phases deteriorates

Engineering Contradiction:
Improvedevice complexityVSAvoidadaptability to movement phases
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The holding device serves multiple functions: it provides reliable locking during stance phase, enables controlled unlocking during swing phase when flexion is needed, and offers overload protection. By designing a single mechanism that responds to flexion moments, the invention achieves multi-functionality without requiring separate damping systems for different movement phases, thereby maintaining simplicity while improving adaptability

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 ensures secure locking during normal activities like standing and walking while allowing flexible movement by unlocking when a predetermined flexion moment is exceeded, providing enhanced safety and support through adjustable damping, thus improving user experience and preventing unintended flexion movements.

Implementation Method 1

The holding device has at least one magnetic coupling

Methodology Applied
Scientific EffectMagnetic coupling: Magnetism

Implementation Method 2

The holding device has at least one magnetic coupling and/or a suction cup coupling

Methodology Applied
Scientific EffectSuction cup coupling: Suction

Implementation Method 3

The holding device has at least one magnetic coupling and/or a suction cup coupling and/or a snap spring

Methodology Applied
Scientific EffectSnap spring: Spring

Implementation Method 4

The holding device has at least one magnetic coupling and/or a suction cup coupling and/or a snap spring and/or a hydraulic locking unit with a switchable check valve

Methodology Applied
Scientific EffectHydraulic locking: Hydraulic Press

Implementation Method 5

a damping device is arranged between the lower part and the upper part, which dampens a flexion movement

Methodology Applied
Scientific EffectDamping: Damping

Data Source

PatentEP3352711B1Orthopedic joint system
Publication Date: 2024.06.19 OTTOBOCK SE & CO KGAA
  • EP3352711B1 patent drawingFigure 1
  • EP3352711B1 patent drawingFigure 2
  • EP3352711B1 patent drawingFigure 3

AI summary

The invention relates to an orthopedic joint device, comprising an upper part (10), on which upper connecting means (11) for fastening to a patient are arranged, and a lower part (30), which is fastened to the upper part (10) with articulation about a pivot axis (20), wherein a flexion-moment-controlled halting device (40) is arranged between the upper part (10) and the lower part (30), which halting device blocks flexion and, when a predetermined flexion moment is exceeded, releases the flexion.