Spacer Core With Acrylic Cement Coating For Drug Release

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current spacer devices for treating arthroprosthesis infections, such as hip prostheses, have limited duration of pharmaceutical and therapeutic product release, requiring prolonged body retention and supporting mechanical stresses, which complicates successful treatment.

Innovation Solution

A core for a spacer device featuring a stem and collar covered with acrylic bone cement containing pharmaceutical products, with through openings for material accumulation, allowing extended release of therapeutic substances and improved mechanical strength.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Duration of action of moving object

If the spacer device remains in the body for a prolonged time period to extend pharmaceutical product release, then the release duration is improved, but the device must support mechanical stresses and loads from patient movements, which complicates the design and may compromise reliability

Engineering Contradiction:
Improverelease duration of pharmaceutical productsVSAvoidmechanical strength under physiological loads
Core Design Contradiction:
Duration of action of moving objectVSReliability

Solution Approach 1:

The spacer device employs a composite structure combining a metallic core (titanium alloy or stainless steel) with acrylic bone cement coating. This composite construction provides both the mechanical strength needed to withstand physiological loads and the capability to deliver pharmaceutical products over extended periods. The metallic core ensures structural integrity while the cement layer enables drug reservoir function.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The acrylic bone cement is applied in a porous state and allowed to solidify, creating a matrix that can store and gradually release pharmaceutical products. The porous structure increases the drug reservoir capacity and controls the release kinetics, enabling prolonged therapeutic action without compromising the mechanical framework.

Inventive Principle:
Principle #31Porous materials

2Duration of action of moving object

If the spacer device is designed with complex structures to improve pharmaceutical product release, then the release efficacy is improved, but the manufacturing complexity and cost increase

Engineering Contradiction:
Improverelease duration of pharmaceutical productsVSAvoidmanufacturing simplicity and cost
Core Design Contradiction:
Duration of action of moving objectVSEase of manufacture

Solution Approach 1:

The pharmaceutical products are incorporated into the acrylic bone cement during the manufacturing process itself, before the spacer is implanted. The cement is mixed with the drugs in the desired concentration and applied to the core in a controlled environment. This preliminary incorporation simplifies production by combining material application and drug loading in a single step, avoiding complex post-manufacturing drug delivery system assembly.

Inventive Principle:
Principle #10Preliminary action

3Weight of moving object

If the spacer device uses lightweight materials to reduce patient burden, then the weight is reduced, but the mechanical strength and ability to support physiological loads may be compromised

Engineering Contradiction:
Improveweight of spacer deviceVSAvoidmechanical strength under physiological loads
Core Design Contradiction:
Weight of moving objectVSStrength

Solution Approach 1:

The spacer utilizes a composite construction with a lightweight metallic core (titanium alloy or stainless steel) that provides high strength-to-weight ratio. The metallic core ensures adequate mechanical strength to support physiological loads while minimizing overall device weight. The acrylic bone cement coating adds minimal weight while providing the pharmaceutical delivery function.

Inventive Principle:
Principle #40Composite materials

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 core enables prolonged release of pharmaceutical and therapeutic products, enhancing treatment efficacy while maintaining mechanical strength and simplicity, reducing production costs, and allowing surgeons to adapt to patient needs.

Implementation Method 1

a layer of a coating material comprising acrylic bone cement... containing said-coating material, or containing a material comprising acrylic bone cement added with one or a plurality of pharmaceutical products or active and/or therapeutic substances

Methodology Applied
Scientific EffectAdsorption: Adsorption

Data Source

PatentEP3397210B1A core for a spacer
Publication Date: 2020.02.19 TECRES SPA
  • EP3397210B1 patent drawingFigure 1
  • EP3397210B1 patent drawingFigure 2~4
  • EP3397210B1 patent drawingFigure 5~7

AI summary

Core (1) for a spacer, comprising a main body that comprises a plurality of through openings (46), adapted to be secured in a corresponding residual bone bed of a previous implant; the main body being adapted to be covered with a layer (S) of a coating material or a material comprising acrylic bone cement added or that can be added with one or a plurality of pharmaceutical products or active and/or therapeutic substances.