Acetabular Implant Asymmetric Screw Fixation and Ledge Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing acetabular implants face challenges in achieving stable fixation to bone tissue, leading to non-uniform stress distribution, increased treatment time, and limitations in osteoplasty performance due to inadequate design and load distribution between pelvic bones.
Innovation Solution
The acetabular implant features a spherical cup with strategically placed through openings for screws, a supporting ledge, and an additional undercut to prevent tissue conflict, allowing for improved load distribution and ease of osteoplasty, while maintaining a low price point and expanding size range.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If annular grooves are provided on the implant surface to enhance fixation, then fixation stability is improved, but bone destruction occurs and treatment period increases
Solution Approach 1:
The implant surface is provided with a porous coating that allows bone ingrowth without requiring deep grooves that would destroy bone. The porous structure provides mechanical interlocking while preserving bone integrity, thereby achieving stable fixation without extending treatment time.
Solution Approach 2:
The implant design incorporates localized features such as porous coating in specific regions and smooth surfaces in others, allowing bone attachment where needed while avoiding bone destruction in critical areas. This selective surface treatment resolves the contradiction between fixation stability and bone preservation.
2Reliability
If clamps are arranged along the same parallel circle to form a rigid rim, then implant fixation stability is improved, but non-uniform stresses and deformities occur due to improper load distribution
Solution Approach 1:
The attachment elements are positioned asymmetrically around the implant rather than uniformly along a parallel circle. This asymmetric arrangement allows for more uniform distribution of loads across the pelvic bones (ilium, pubis, ischium), preventing the non-uniform stresses and deformities that would result from symmetric rigid rim formation.
Solution Approach 2:
Different regions of the implant are equipped with attachment elements according to the specific load-bearing requirements of each pelvic bone. The ilium, pubis, and ischium receive appropriate fixation elements positioned to match their structural characteristics, achieving uniform stress distribution through localized adaptation.
3Ease of operation
If through openings are strategically placed and supporting ledge is formed, then osteoplasty accessibility is improved, but device complexity increases
Solution Approach 1:
The implant is designed with segmented features including through openings positioned to provide access to the acetabular floor and a supporting ledge that creates distinct functional zones. This segmentation allows surgeons to perform osteoplasty procedures through predetermined access points without requiring complex external instrumentation, balancing accessibility with structural simplicity.
Data Source
AI summary
The invention relates to traumatic surgery and orthopedics and is intended for hip acetabular replacement. In a spherical cup of an acetabular implant, in the region of the apex of a hemisphere, a through opening is provided for osteoplasty of the acetabular floor, and the spherical segment of the surface between the edge of the rim of the cup and an opening for a screw for fastening in the ilium is larger than the spherical segments of the surface between said edge and openings for screws for fastening in the pubis and the ischium, thus forming a supporting ledge in the region of the body of the ilium. Said ledge can be extended into the region of an outer spherical surface of the cup which is formed by an angle α in a range of 1°-30° between diametral planes and which is adjacent to the equatorial plane of the hemisphere. On the portions of the segments of the spherical surface between the edge and the openings for the screws for fastening in the pubis and the ischium, the spherical cup can be additionally cropped to prevent conflict the between soft tissues and implant components. The resulting additional undercut can be cropped in the region of outer spherical surface, which is formed by the angle β between the diametral planes in the range of 1° to 20° and which is adjacent to the equatorial plane of said hemisphere.