Femoral Offset Instrument Modular Reaming Guide
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
During revision knee surgeries, existing orthopaedic instruments face challenges in accurately preparing the patient's femur to receive a new orthopaedic prosthesis, particularly in achieving the correct offset orientation and reaming depth, which can lead to suboptimal implantation and stability of the prosthetic components.
Innovation Solution
The method involves using a stem trial attached to an offset tool to advance through the femur's medullary canal, positioning a surgical block, and employing a cannulated reamer to define a chamber, followed by securing an intramedullary orthopaedic surgical instrument. This process includes locking mechanisms and indicators to ensure precise alignment and depth, allowing for the correct placement and rotation of prosthetic components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional orthopaedic instruments are used for revision knee surgery, then the surgical procedure can be completed, but the precision of offset orientation and reaming depth is insufficient
Solution Approach 1:
The orthopaedic surgical instrument is divided into multiple functional modules: an intramedullary adapter with offset adjustment mechanism, a reamer guide assembly with depth indicators, and a cutting block with alignment features. Each module independently performs a specific function (offset setting, depth control, orientation alignment), allowing precise control of reaming parameters while maintaining manageable overall complexity through modular design.
Solution Approach 2:
The instrument pre-establishes the desired offset orientation and reaming depth before the actual reaming operation. The intramedullary adapter is configured with the target offset value, depth indicators are set to the required reaming depth, and alignment features are positioned to define the correct orientation. This preliminary configuration ensures that when reaming occurs, the precise parameters are automatically achieved without requiring complex real-time measurements during surgery.
2Manufacturing precision
If conventional instruments are used, then surgery can proceed, but reaming depth control is inaccurate
Solution Approach 1:
The reamer guide assembly includes pre-set depth indicators that are configured before surgery or adjusted to the required depth prior to reaming. These indicators visually mark the precise reaming depth on the intramedullary canal, allowing the surgeon to stop reaming at the exact desired depth without complex measurement procedures during the operation.
Solution Approach 2:
The reamer guide assembly acts as an intermediary between the reaming tool and the intramedullary canal. It provides a mechanical guide that physically limits the reaming depth through its structure and visual indicators, mediating the reaming process to ensure accurate depth control while simplifying the surgeon's task of depth monitoring.
3Reliability
If existing instruments are used for femur preparation, then the procedure can be completed, but implant stability is compromised
Solution Approach 1:
The instrument assembly is segmented into specialized components: an intramedullary adapter for precise offset positioning, a reamer guide assembly for accurate depth and orientation control, and a cutting block for consistent resection. Each segment contributes to achieving optimal implant alignment and positioning, which directly improves implant stability and longevity, while the modular nature keeps individual components manageable.
Solution Approach 2:
The instrument replaces manual estimation and rough mechanical alignment with precision-engineered mechanical guides and indicators. The offset adjustment mechanism uses precise mechanical linkages to set specific offset values, depth indicators provide visual feedback for accurate depth measurement, and alignment features ensure correct orientation. This substitution of rough mechanical approximation with precision mechanical guidance improves implant stability.
Data Source
AI summary
A number of orthopaedic surgical instruments for use in a surgical procedure to prepare a patient's femur to receive an orthopedic prosthesis. The tools include guide tools, cutting tools, surgical blocks, and other orthopaedic surgical instruments configured to plan and guide the preparation of the patient's femur. A method of using the orthopaedic surgical instruments is also disclosed.