Intramedullary Ankle Arthrodesis Implant Internal Compression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for joint fusion, such as arthrodesis, often require external compression, which can be invasive and lead to issues like bone misalignment and patient trauma, as they do not allow for internal compression across joints.
Innovation Solution
An intramedullary ankle arthrodesis implant with elongate shafts and slots that enable internal compression across the tibio-talar and subtalar joints through fixation members and a telescoping clamp system, allowing for axial translation of screws to compress bones internally.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If external compression is used to bring bones into apposition, then joint compression can be achieved, but patient trauma and bone misalignment occur
Solution Approach 1:
The patent inverts the traditional external compression approach by implementing internal compression through the intramedullary implant. Instead of applying force from outside the bone, the compression is applied from within the medullary canal through fixation members that translate along slots in the implant, directly compressing the joint surfaces internally.
Solution Approach 2:
The fixation members (screws or bone fasteners) act as intermediaries between the intramedullary implant and the bone. These fixation members translate along the elongate slots of the implant to transmit compressive force to the joint surfaces, enabling internal compression without direct external contact with the bone surfaces.
2Ease of operation
If fixation members are allowed to translate along elongate slots for internal compression, then internal joint compression is achieved, but device complexity increases
Solution Approach 1:
The implant incorporates dynamic elements through the elongate slots that allow fixation members to translate along their length. This dynamic capability enables the implant to adjust and apply compression internally as the bones heal and settle, transforming a static implant into a dynamic compression system.
Solution Approach 2:
The implant is segmented into multiple functional components: the intramedullary shaft, elongate slots for fixation member translation, and multiple fixation members positioned at different locations. This segmentation allows independent control of compression at different joint levels (tibio-talar and subtalar joints) through the telescoping clamp system.
3Manufacturing precision
If multiple fixation members are used for two-stage compression of tibio-talar and subtalar joints, then precision of joint fusion is enhanced, but manufacturing complexity increases
Solution Approach 1:
The intramedullary implant serves multiple functions simultaneously: it provides structural support within the medullary canal, contains elongate slots for fixation member translation, provides angled openings for screw insertion into different bones (tibia, talus, calcaneus), and enables two-stage compression of different joints. This multi-functionality consolidates what would otherwise require multiple separate devices into a single universal implant.
Data Source
Figure 1
Figure 2A~2B
Figure 2C~3
AI summary
Various intramedullary implants, instruments, and methods are disclosed herein. In an example, a compression instrument is used to provide internal compression of bones adjoining a joint or bones spanning a fracture to cause compression of the joint or fracture.