Abstract
Glenoid component stability is essential to ensure successful long-term survivability following total shoulder arthroplasty. As such, this computational study assessed the stability of five all-polyethylene glenoid components (Keel, Central-Finned 4-Peg, Peripheral 4-Peg, Cross-Keel, and Inverted-Y), using simulated joint loading in an osteoarthritic patient cohort. Stability was assessed on the basis of component micromotion in the tangential and normal directions. Maximum tangential micromotion occurred in the Cross-Keel (146 ± 46 µm), which was significantly greater (p < .001) than the other components. Maximum normal micromotion occurred in the Inverted-Y (109 ± 43 µm), which was significantly greater (p ≤ .002) than the other four components. In general, the Central-Finned 4-Peg exhibited the least normal and tangential micromotion, while the keeled components shown the highest normal and tangential micromotion. This study suggests that modifications to keeled designs do not improve component stability under the conditions tested, and pegged components show superior computational stability.
Acknowledgements
Nikolas K. Knowles is supported in part by the Natural Sciences and Engineering Research Council of Canada and by a Transdisciplinary Bone & Joint Training Award from the Collaborative Training Program in Musculoskeletal Health Research at The University of Western Ontario.
Disclosure statement
The authors (NKK, GDGL & LMF), their immediate families, and any research foundations with which they are affiliated have not received any financial payments or other benefits from any commercial entity related to the subject of this article. Institutional Review Board Approval (IRB) was obtained from the Western University Health Science Research Ethics Board (Approval #105912). The author (GSA) is a consultant for Wright/Tornier Inc, Imascap, and Depuy Synthes. Additionally, he has received research support from Tornier Inc, Depuy Synthes and Exactech for research related to the subject of this article. No company had any input in to the study design, protocol, testing, data analysis or manuscript preparation.