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Updated: Sep 29, 2025

Measuring 3D In-vivo Shoulder Kinematics using Biplanar Videoradiography
Published on: March 12, 2021
Are differences in shoulder morphology and hand dominance risk factors for rotator cuff tears?
1Department of Orthopaedic Surgery, University of Missouri Kansas City, Kansas City, Missouri (MO), USA. mahmut_aydn@windowslive.com.
Objective:
The purpose of this study was to evaluate whether there was a difference in shoulder morphology and hand dominance between a healthy shoulder and a shoulder with rotator cuff tear (RCT) in the same patient.
Patients And Methods:
Between 2015 and 2020, 120 shoulders from 60 patients with complete RCT and contralateral intact rotator cuffs were enrolled in this retrospective analysis. Physical examinations, shoulder radiographs, and magnetic resonance imaging (MRI) pictures of the patients were reviewed. On radiographs, the AT, CSA, LAA, and AI values were compared between shoulders with complete RCT and contralateral healthy shoulders from the same individuals. Additionally, the association between hand dominance and RCT was evaluated.
Results:
This study enrolled 60 patients. 59.17% of the participants are female, and 40.83% are male. The mean age of the patients was 54.5±7.1 years. There were statistically significant differences in AI, CSA, and LAA measurements between the study group (RCT group) and the control group. There was no significant difference in AT between the two groups.
Conclusions:
There are morphological differences between a healthy shoulder and a shoulder with an RCT in the same patient, and these differences (LAA/CSA/AI/AT) may have an effect on the prevalence of RCT.
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