Computer-Assisted Orthopedic Alignment Guide with 5-DOF Parallel Manipulator
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current surgical techniques for total knee arthroplasty (TKA) face challenges in achieving accurate alignment of prosthetic components, leading to issues like polyethylene wear, aseptic loosening, and higher revision rates due to malrotation and malalignment, despite the use of various alignment guides.
Innovation Solution
A compact and reduced alignment guide system utilizing an intraoperative navigation system and a five-degree-of-freedom parallel manipulator with ball head fasteners and sockets, allowing for precise adjustments in three degrees of freedom to align implant components accurately during TKA.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional alignment guides are used in TKA, then surgical procedure can be performed, but alignment accuracy is insufficient leading to malalignment and malrotation
Solution Approach 1:
The patent replaces traditional mechanical alignment guides with a computer-assisted navigation system that uses electronic sensors, processors, and display devices to determine and guide component alignment. The navigation system calculates alignment parameters electronically and provides real-time feedback to the surgeon through visual displays, eliminating reliance on purely mechanical guide structures.
Solution Approach 2:
The navigation system continuously monitors the position and orientation of implant components during surgery, providing real-time feedback through visual displays. The system compares actual component placement against pre-planned alignment targets and allows for intraoperative adjustment, creating a closed-loop control system that improves alignment accuracy.
2Manufacturing precision
If conventional alignment guides are used, then surgery can proceed, but drilling accuracy is insufficient resulting in outliers
Solution Approach 1:
The patent replaces complex mechanical drilling guides with a navigation system that uses electronic tracking of surgical instruments. Sensors attached to drilling tools provide real-time position data to the computer system, which calculates and displays the precise location and orientation of drill holes on a monitor, eliminating the need for complex mechanical guide structures.
Solution Approach 2:
The navigation system creates a virtual copy or digital representation of the patient's anatomy and surgical plan on a computer display. This virtual model allows the surgeon to visualize and verify drilling accuracy without physical contact, providing a digital reference that guides precise hole placement.
3Measurement precision
If traditional surgical techniques are used, then procedure can be completed, but component alignment is imprecise leading to polyethylene wear
Solution Approach 1:
The navigation system provides continuous visual feedback during the surgical procedure, displaying the real-time position and orientation of implant components against pre-planned alignment targets. This allows the surgeon to make incremental adjustments and verify alignment accuracy throughout the procedure, improving precision without significantly increasing operational complexity.
Solution Approach 2:
The system performs preoperative planning and creates a virtual surgical plan before the actual surgery. This preliminary action establishes target alignment parameters and component positions in advance, allowing the surgeon to follow a predetermined accurate path during the procedure rather than relying on intraoperative estimation.
4Reliability
If simple alignment guides are used, then device complexity is low, but alignment stability is insufficient
Solution Approach 1:
The patent replaces mechanical alignment guide structures with a computer-based navigation system that uses electronic sensors and software algorithms to maintain and verify alignment stability. The system continuously tracks component positions and provides digital reference frames that remain stable throughout the procedure without requiring complex mechanical fixation structures.
Data Source
Figure 1A
Figure 1B
Figure 1C
AI summary
In an embodiment, the methodology of the present invention is based on the use of an intraoperative navigation system and of a compact alignment guide for alignment of implant components. In an embodiment, an alignment guide of the present invention includes a first component fixable to a bone element; a second mobile component, and a third mobile component, wherein the second mobile component and two control mechanisms form a first link, wherein the two control mechanisms are working in parallel to perform adjustments in two degrees of freedom, wherein the third mobile component and three control mechanisms form a second link, wherein the three control mechanisms are working in parallel to perform adjustments in three additional degrees of freedom, and wherein the first link adjustments and the second link adjustments are performed in series to provide a total adjustment of five degrees of freedom relative to the first component.