Radiolucent Grid Plate for Hip Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for intraoperative fluoroscopic guidance in total hip arthroplasty face challenges in accurately positioning the acetabular component due to variability in patient anatomy, with current devices being either invasive or limited in application scope.
Innovation Solution
A dimensioned radiolucent grid plate apparatus with a known quantifiable grid pattern and angled lines is used in conjunction with x-rays to measure and determine leg length, offset, and cup position, allowing for precise alignment and positioning of hip implants across various orthopedic procedures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a tripod device or alignment fixture is used to guide acetabular component positioning, then positioning accuracy is improved, but the device becomes invasive or implantable
Solution Approach 1:
The patent introduces a radiopaque alignment guide as an intermediary tool that can be temporarily positioned on the patient's anatomy during surgery to provide precise positioning guidance for the acetabular component. This intermediary device allows accurate measurement and alignment without requiring permanent implantation or invasive procedures, as it can be removed after the implant is positioned correctly
Solution Approach 2:
The patent replaces complex mechanical alignment fixtures with a radiopaque guide that works in conjunction with fluoroscopic imaging. Instead of relying solely on mechanical contact points and physical guides, the system uses visual feedback from X-ray imaging to achieve precise positioning, reducing the need for invasive mechanical structures
2Ease of operation
If a transverse acetabular ligament is used as an orientation marker, then positioning guidance is provided, but reliability is reduced due to acetabular deterioration from arthritis
Solution Approach 1:
The patent creates a radiopaque copy or representation of the desired acetabular orientation that can be superimposed on fluoroscopic images. This radiopaque guide replicates the orientation information that would normally come from anatomical landmarks, but does so in a way that is independent of degraded anatomy, providing reliable positioning guidance even when natural landmarks are compromised by arthritis
Solution Approach 2:
The alignment guide is prepared in advance with pre-marked orientation lines and positioning references that correspond to the desired acetabular component orientation. This preliminary preparation allows the surgeon to directly transfer the correct orientation to the implant without relying on real-time interpretation of degraded anatomical structures
3Reliability
If intraoperative fluoroscopy is used to assess radiographic parameters, then wear and stability can be evaluated, but positioning precision is insufficient for optimal implant placement
Solution Approach 1:
The patent implements a feedback system where the radiopaque alignment guide is visualized in real-time on fluoroscopic images during the implantation process. The surgeon can observe the position of the guide relative to anatomical landmarks and adjust the acetabular component positioning accordingly, providing continuous visual feedback to achieve precise placement rather than relying on postoperative assessment alone
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 apparatus enhances precision and accuracy in orthopedic surgeries by providing subject-specific data for leg length, offset, and cup position, reducing malpositioning and symptomatic leg length discrepancies, and facilitating fracture reduction and deformity correction.
Implementation Method 1
A plurality of spring-loaded devices mediate the movement of the grid
Implementation Method 2
employes x-rays to obtain an image that shows the position of the pelvis and both proximal femurs relative to the dimensioned grid plate
Data Source
Figure 1
Figure 2~3
Figure 4A~4B
AI summary
A dimensioned grid apparatus for determining: 1) leg length, offset, and cup position during arthroplasty replacement surgery; 2) fracture reduction/correction position during trauma procedures and 3) an apparatus to be used for deformity correction planning is provided.