Osteoconductive Insert for ACL Graft Bone Integration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current ACL reconstruction methods face challenges such as donor site morbidity, immune response, mechanical mismatch, and poor graft integration, leading to instability and potential secondary osteoarthritis, particularly with non-osteoconductive grafts and hamstring autografts which are painful and result in inferior mechanical stability.
Innovation Solution
A medical implant device featuring synthetic osteoconductive and osteoinductive inserts, such as tricalcium phosphate, combined with a flexible graft to create a 'bone-ligament-bone' configuration, enhancing bone integration and stability by promoting rapid biological attachment and minimizing pain associated with bone block extraction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If non-osteoconductive graft material is used, then immune response and disease transmission are avoided, but bone integration is delayed and bone tunnel expansion occurs
Solution Approach 1:
The patent uses an osteoconductive coating as an intermediary layer between the non-osteoconductive graft material and the bone tunnel. This coating promotes bone ingrowth and integration while the underlying non-osteoconductive material maintains its advantages of avoiding immune response and disease transmission. The coating acts as a mediator that enables bone integration without requiring the bulk graft material to be osteoconductive.
Solution Approach 2:
The patent employs porous osteoconductive coating materials that allow bone ingrowth through their porous structure. The porosity enables osteoblasts to migrate into and through the coating, facilitating bone integration and preventing bone tunnel expansion while maintaining the benefits of using non-osteoconductive graft material.
2Reliability
If bone blocks are cut for autograft, then rapid bone integration is achieved, but donor site morbidity and patient pain increase
Solution Approach 1:
The osteoconductive coating serves as a mediator that enables rapid bone integration without requiring bone blocks to be harvested from the patient. The coating provides the osteoconductive properties that would otherwise require actual bone tissue, thereby avoiding donor site morbidity and patient pain while achieving the same integration speed.
Solution Approach 2:
The patent creates a functional copy of bone's osteoconductive properties through the application of osteoconductive coatings on the graft material. Instead of using actual bone blocks, the coating replicates the bone-like surface properties that promote osteoblast attachment and bone ingrowth, achieving similar integration results without the need for bone harvesting.
3Object-affected harmful factors
If hamstring autograft is used, then donor site pain is reduced, but mechanical stability and graft integration are inferior
Solution Approach 1:
The patent applies porous osteoconductive coatings to the hamstring graft that facilitate rapid bone ingrowth and integration. The porous structure provides a scaffold for osteoblasts to migrate into and form bone tissue, significantly improving mechanical stability and graft integration compared to uncoated hamstring grafts, while maintaining the advantage of reduced donor site pain.
Solution Approach 2:
The patent creates a composite structure by combining the hamstring autograft material with osteoconductive coating materials. This composite approach allows the graft to maintain the advantages of hamstring tissue (reduced donor site pain) while the added osteoconductive coating provides the mechanical stability and bone integration properties that hamstring tissue alone lacks.
4Strength
If interference screws are used for fixation, then graft anchoring is achieved, but physiological healing is blocked
Solution Approach 1:
The osteoconductive coating acts as a mediator that enables physiological healing through bone ingrowth while still providing secure graft anchoring. Unlike interference screws that mechanically block healing, the coating promotes natural osteoblast migration and bone formation, achieving both strong anchoring and physiological healing processes.
Solution Approach 2:
The patent replaces the mechanical fixation system (interference screws) with a bioactive system based on osteoconductive coatings. Instead of relying on mechanical interlocking that blocks healing, the system uses bioactive materials that promote physiological bone ingrowth, achieving secure anchoring through biological integration rather than mechanical obstruction.
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 achieves improved initial and long-term stability of the ACL graft, reducing the risk of secondary osteoarthritis and patient discomfort by facilitating rapid bone ingrowth and integration, thus enhancing the success of ACL reconstruction.
Implementation Method 1
synthetic osteoconductive and osteoinductive inserts, such as tricalcium phosphate
Implementation Method 2
synthetic osteoconductive and osteoinductive inserts, such as tricalcium phosphate
Data Source
Figure 1
Figure 5
Figure 6
AI summary
The invention relates to a medical implant device for attaching or re-attaching a flexible graft to a bone, comprising: at least a first insert comprising a synthetic osteoconductive and/or osteoinductive material, and a flexible graft, wherein the flexible graft is connected to the at least one insert, particularly prior to surgical implantation of the medical implant device.