Margaret S Coats-Thomas1, Daniel F Massimini, Jon J P Warner, Amee L Seitz. 1. From the Northwestern University, Feinberg School of Medicine, Chicago, Illinois (MSC-T); Boston Scientific Corporation, Maple Grove, Minnesota (DFM); MGH Shoulder Service, Boston Shoulder Institute, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (JJPW); and Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, Illinois (ALS).
Abstract
OBJECTIVE: The study aim was to evaluate subacromial and internal impingement risk between shoulders (dominant/nondominant) during dynamic motion using subject-specific anatomy and precise in vivo kinematics. DESIGN: In a prospective cross-sectional study, nine subjects underwent bilateral magnetic resonance (N = 18 shoulders) and fluoroscopic imaging during elevation and external rotation at 90 degrees of abduction. Subject-specific bone models were created and distances from footprint to (a) acromion and (b) glenoid were measured to evaluate risk. RESULTS: Throughout elevation, subacromial impingement risk was greater in the dominant shoulder (P = 0.0178). Regardless of side, high subacromial impingement risk occurred at 30% (78 degrees), 50% (101 degrees), and 70% (57 degrees) of the elevation cycle (P < 0.0001). High subacromial impingement risk also occurred at 30% (94 degrees), 50% (120 degrees), and 70% (63 degrees) of the external rotation motion cycle (P < 0.0001). Throughout both motions, internal impingement risk was not observed; however, the footprint and glenoid were closest at 50% of the elevation (101 degrees) and external rotation (120 degrees) cycles (P < 0.0001). CONCLUSIONS: During elevation, subacromial impingement risk is greatest at lower arm positions (30% cycle, 78 degrees) and is greater in the dominant shoulder. High subacromial impingement risk also occurs with external rotation (63-120 degrees). Internal impingement risk does not occur with maximal elevation (101 degrees) or external rotation at 90-degree abduction but is more closely approached with elevation.
OBJECTIVE: The study aim was to evaluate subacromial and internal impingement risk between shoulders (dominant/nondominant) during dynamic motion using subject-specific anatomy and precise in vivo kinematics. DESIGN: In a prospective cross-sectional study, nine subjects underwent bilateral magnetic resonance (N = 18 shoulders) and fluoroscopic imaging during elevation and external rotation at 90 degrees of abduction. Subject-specific bone models were created and distances from footprint to (a) acromion and (b) glenoid were measured to evaluate risk. RESULTS: Throughout elevation, subacromial impingement risk was greater in the dominant shoulder (P = 0.0178). Regardless of side, high subacromial impingement risk occurred at 30% (78 degrees), 50% (101 degrees), and 70% (57 degrees) of the elevation cycle (P < 0.0001). High subacromial impingement risk also occurred at 30% (94 degrees), 50% (120 degrees), and 70% (63 degrees) of the external rotation motion cycle (P < 0.0001). Throughout both motions, internal impingement risk was not observed; however, the footprint and glenoid were closest at 50% of the elevation (101 degrees) and external rotation (120 degrees) cycles (P < 0.0001). CONCLUSIONS: During elevation, subacromial impingement risk is greatest at lower arm positions (30% cycle, 78 degrees) and is greater in the dominant shoulder. High subacromial impingement risk also occurs with external rotation (63-120 degrees). Internal impingement risk does not occur with maximal elevation (101 degrees) or external rotation at 90-degree abduction but is more closely approached with elevation.
Authors: Joseph D Mozingo; Mohsen Akbari-Shandiz; Naveen S Murthy; Meegan G Van Straaten; Beth A Schueler; David R Holmes; Cynthia H McCollough; Kristin D Zhao Journal: Clin Biomech (Bristol, Avon) Date: 2019-10-20 Impact factor: 2.063
Authors: Melina N Haik; Francisco Alburquerque-Sendín; Ricardo A S Fernandes; Danilo H Kamonseki; Lucas A Almeida; Richard E Liebano; Paula R Camargo Journal: Diagnostics (Basel) Date: 2020-11-10