Shoulder Arthroplasty Cut Guide with Multi-Axis Positioning Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The minimally invasive surgery (MIS) technique for shoulder joint procedures faces limited access for surgeons during humeral head resection, necessitating improved instrumentation for enhanced flexibility and efficiency in resecting the humerus while avoiding muscle resection.
Innovation Solution
The development of an instrument assembly comprising a cut guide with a slot and a positioning assembly that includes a boom and an arm, allowing for precise positioning relative to the humeral head along multiple axes, along with a visualization instrument that can be selectively removed from a reamer along its longitudinal length, facilitating more efficient and flexible resection procedures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If MIS technique is used to avoid resecting suprascapularis and infraspinatus muscles, then muscle preservation is improved, but surgical access and instrument positioning become limited
Solution Approach 1:
The positioning assembly is divided into separate components including a reamer, a cut guide, and a positioning mechanism with multiple degrees of freedom. This segmentation allows each component to be optimized independently - the reamer provides stable anchoring while the cut guide can be precisely positioned without requiring wide surgical exposure
Solution Approach 2:
The positioning assembly incorporates dynamic positioning capabilities with the arm moveable about the reamer in a second axis, allowing the surgeon to adjust the cut guide position intraoperatively. This dynamic adjustment enables precise instrument positioning through limited access without requiring extensive muscle resection
2Ease of operation
If standard superior approach technique is used for humeral head resection, then surgical access is improved, but suprascapularis and infraspinatus muscles must be resected
Solution Approach 1:
The reamer acts as an intermediary device that is inserted into the humerus through limited access and provides a stable anchor point. This intermediary allows the cut guide to be positioned precisely without requiring direct access to the humeral head through muscle resection
Solution Approach 2:
The positioning assembly adds dimensional flexibility by allowing movement along multiple axes - the boom positions the cut guide along a first axis and the arm positions it about the reamer in a second axis. This multi-dimensional positioning capability enables precise instrument placement through limited surgical access
3Stability of the object's composition
If sizer/visualization instrument is removed only from end of reamer, then instrument stability is maintained, but procedure time and complexity increase
Solution Approach 1:
The slot in the sizer/visualization instrument provides dynamic removal capability, allowing the instrument to be withdrawn at any position along the reamer length. This dynamic design maintains stability during use while enabling flexible, rapid removal when needed, reducing procedure time without compromising instrument stability
Data Source
AI summary
An instrument assembly for a shoulder arthroplasty that can comprise: a cut guide having a slot for aiding a resection of a head of a humerus; and a positioning assembly configured to position the cut guide relative to the head of the humerus, wherein the positioning assembly is configured to couple to a reamer. The positioning assembly can comprise: a boom configured to position the cut guide relative to the reamer and the head of the humerus along a first axis; and an arm coupled to the cut guide and configured to be moveable to position the cut guide relative to the head of the humerus about the reamer in a second axis.