Bone and Joint Institute
Hemiarthroplasty of the elbow: The effect of implant size on joint congruency
Document Type
Article
Publication Date
2-1-2016
Journal
Journal of Shoulder and Elbow Surgery
Volume
25
Issue
2
First Page
297
Last Page
303
URL with Digital Object Identifier
10.1016/j.jse.2015.09.022
Abstract
© 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Background: Distal humeral hemiarthroplasty is a treatment option for elbow joint disease that predominantly affects the distal humerus, including distal humerus fractures, nonunions, and avascular necrosis. The effect of hemiarthroplasty implants on joint contact has not been reported. The purpose of this in vitro study was to quantify the effects of hemiarthroplasty and implant size on ulnohumeral joint congruency. Methods: Five fresh frozen cadaveric upper extremities were mounted to a custom elbow testing system. Active and passive motion were performed in dependent, horizontal, varus, and valgus positions. A registration and interbone distance algorithm was used to quantify ulnohumeral joint congruency throughout elbow flexion. Results: The optimally sized hemiarthroplasty implant demonstrated the greatest joint congruency with the ulna, followed by the oversized implant, then the undersized implant. Joint congruency was greater during active vs. passive flexion, indicating that the elbow joint is more reduced in active flexion than in passive flexion. Conclusion: This study demonstrates that undersized distal humeral hemiarthroplasty implants have the lowest joint congruency compared with an optimally sized or oversized implant.
