Hardenable Filler Anchoring Graft to Bone via Expansion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for anchoring grafts to bone, such as using screws and sutures, often result in device failure, tissue damage, and delayed healing due to high torque requirements and potential for infection.
Innovation Solution
A surgical method involving the formation of a bone cavity with a hardenable filler material that expands within a flexible sac, securing the graft against the bone cavity walls once hardened, eliminating the need for fixation screws and reducing tissue and bone damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional attachment devices such as screws and sutures are used to anchor grafts to bone, then the graft can be attached to the bone, but the devices may crack, break, or fail during or after implantation, causing delayed healing and potential injury to the patient
Solution Approach 1:
The patent removes the traditional fixation screw from the system and replaces it with a graft fixation device that uses an expandable balloon mechanism. This extraction of the problematic screw element eliminates the associated risks of screw breakage and reduces the need for high-torque insertion that causes tissue damage.
Solution Approach 2:
The patent introduces a balloon as an intermediary element between the graft and bone. The balloon is inserted into a cavity formed in the bone, inflated to expand and secure the graft against the bone walls, and then deflated and removed. This intermediary mechanism provides reliable fixation without the need for permanent penetrating screws that risk failure.
2Strength
If interference screws are used to hold the graft against the bone inside a bone tunnel with high interference, then the graft can be securely fixed, but the high torque requirements can cause device failure and bone or graft damage
Solution Approach 1:
The patent replaces the mechanical interference fit system (screw with high torque requirements) with a pneumatic/hydrostatic expansion system. The balloon is inflated with fluid to expand radially and secure the graft against the bone walls, eliminating the need for high torque mechanical insertion and the associated damage.
Solution Approach 2:
The patent changes the fixation mechanism from a static mechanical interference fit to a dynamic expansion process. The balloon transitions from a deflated state to an inflated state, changing its volume and pressure parameters to secure the graft. This parameter-based mechanism provides strong fixation without the mechanical damage of high-torque screw insertion.
3Ease of operation
If the graft is pulled or pushed into a bone tunnel using various methods, then the graft can be positioned, but the approach does not provide aperture fixation and can lead to tunnel widening due to abrasion from sutures or cords during movement
Solution Approach 1:
The patent uses a balloon as an intermediary tool to achieve both graft positioning and aperture fixation. The balloon is inflated within the bone cavity to push the graft into its final position and simultaneously expand against the bone walls to create a secure fixation, eliminating the need for separate sutures or cords that cause abrasion.
Solution Approach 2:
The patent combines the functions of graft positioning and aperture fixation into a single operation using the expandable balloon. The inflation process simultaneously achieves the graft's final positioning and creates the fixation mechanism, eliminating the need for separate steps and the associated abrasion from multiple sutures or cords.
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 method securely anchors the graft to the bone, reducing the risk of device failure and tissue damage, promoting stable healing without the need for additional anchoring devices.
Implementation Method 1
A hardenable filler material is inserted in a first state into the cavity, the hardenable filler material causing the first portion of the graft to contact and push against walls of the cavity such that when the hardenable filler material changes from the first state to a second, harder state, the first portion of the graft is prevented from exiting the cavity through the first access tunnel
Data Source
AI summary
Methods and devices are provided for anchoring graft to bone. In one exemplary embodiment, a bone cavity is created in bone, a graft is partially advanced into the bone cavity, and a hardenable filler material is inserted into the cavity. The hardenable filler material can change from a viscous first state to a harder second state, compressing the graft against the walls of the bone cavity and thereby anchoring the graft within the cavity. The hardenable filler material can be inserted in an open sac, a closed sac, other carriers or housings, or directly into the bone cavity.