Surgical Parameters During Reverse Shoulder Arthroplasty Predict Post-Surgical Kinematics During the Hand-to-Head Motion

• Published in: Annals of biomedical engineering 2024-09
• Main Authors: Rai, Ajinkya A, LeVasseur, Clarissa M, Kane, Gillian E, Munsch, Maria A, Como, Christopher J, Gabrielli, Alexandra S, Hughes, Jonathan D, Anderst, William J, Lin, Albert
• Format: Article
• Language: English
• ISSN: 0090-6964; 1573-9686; 1573-9686
• DOI: 10.1007/s10439-024-03621-x

This study aimed to identify surgical parameters during reverse shoulder arthroplasty (RSA) that predict post-surgical kinematics during the hand-to-head motion (H2H) and to identify associations between kinematics and outcomes. We hypothesized that greater humeral retroversion and lateralization predict kinematics, and that more scapular upward rotation is associated with better PROs and more range of motion (ROM). Thirty-five post-RSA patients consented to participate. All surgical parameters were recorded while operating or measured on CT. Participants performed H2H while synchronized biplane radiographs were collected at 50 images/second. Digitally reconstructed radiographs were matched to biplane radiographs to determine glenohumeral and scapular kinematics. For all rotations, the contribution, end position, peak angles, and ROM were calculated. Contact path between the glenosphere and polyethylene insert was calculated. Patient-reported outcomes (PROs), clinical ROM, and strength were measured. Multiple linear regression identified surgical parameters that predicted kinematics, and Pearson correlation identified associations between kinematics and outcomes. Less humeral retroversion predicted greater peak abduction (p = 0.035). Humeral neck-shaft angle, retroversion, and glenoid tilt predicted the peak posterior contact path (p = 0.012). Better PROs were associated with more superior contact path (p