Skull Clamp Joint Assembly for MRI Table Positioning
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Solution Overview
Problem
Current headrest systems for medical procedures lack adjustable and versatile solutions for stabilizing patients during surgery, imaging, and transportation, particularly in MRI environments where space constraints and varying patient positions pose challenges.
Innovation Solution
A medical apparatus comprising a transport table, a table adapter, a joint assembly, and a skull clamp that allows for adjustable positioning and stabilization of a patient's head, enabling rotation, height adjustment, and lateral movement to accommodate different procedures and environments, including MRI gantries.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a fixed headrest system is used, then the structure is simple and stable, but it cannot accommodate varying patient positions and procedure requirements
Solution Approach 1:
The headrest system incorporates multiple joints (proximal and distal) that enable dynamic adjustment in multiple directions (e.g., lateral, vertical, rotational). These joints allow the system to transition from a fixed to a dynamically adjustable configuration, accommodating various patient positions and procedural requirements while maintaining structural stability through controlled movement mechanisms.
Solution Approach 2:
The headrest system is divided into multiple independent components including a proximal joint assembly, a distal joint assembly, and intermediate segments. Each segment can be independently adjusted, allowing versatile positioning without requiring complete system redesign. This segmentation enables adaptability while keeping individual component complexity manageable.
2Adaptability or versatility
If the headrest system is made adjustable in multiple directions, then versatility improves, but the system height increases and may not fit in MRI gantries
Solution Approach 1:
The joint assemblies are designed with nested structures where components are housed within one another when not in use. The proximal and distal joints can be retracted into compact configurations, minimizing the overall system height. This nesting allows the system to achieve multi-directional adjustability while maintaining a compact profile that can fit within MRI gantry constraints.
Solution Approach 2:
The system employs rotational joints that allow adjustment in multiple directions without necessarily increasing vertical height. By utilizing angular and rotational degrees of freedom rather than purely vertical extension, the system achieves versatile positioning capability while controlling the footprint and overall dimensions, particularly the height parameter critical for MRI compatibility.
3Reliability
If locking mechanisms are added to maintain position, then stability improves, but the device complexity increases
Solution Approach 1:
The joint assemblies incorporate self-locking mechanisms that automatically maintain positioned once adjusted. The locking features engage passively based on the joint's position and load conditions, eliminating the need for separate active locking components or continuous power supply. This self-service approach ensures position stability during procedures while avoiding the complexity of additional actuated locking systems.
Solution Approach 2:
Friction elements and geometric constraints act as intermediaries between the joint components, providing inherent position holding capability. These passive mechanical features mediate the interaction between moving and fixed parts, ensuring stability without requiring complex active locking mechanisms. The intermediary elements distribute loads and maintain positioning through distributed mechanical engagement rather than concentrated locking components.
Data Source
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AI summary
A table adapter and joint assembly are configured for use with a table during a medical procedure, e.g. a medical imaging procedure or combined imaging and surgical procedure. The table adapter is connectable, directly or indirectly, to a portion of the table. The joint assembly connects with the table adapter about a shaft such that the joint assembly is rotatably adjustable. A head fixation device in the form of a skull clamp is attachable to the joint assembly. The joint assembly generally has a parallelogram shape that has four joints for adjustment where these four joints can be selectively locked or unlocked relative to each other using a single actuator.