Kinematic analysis of the shoulder complex after anatomic and reverse total shoulder arthroplasty: A cross-sectional study

• Published in: Musculoskeletal science & practice 2017-06, Vol.29, p.84-90
• Main Authors: Roren, Alexandra, Nguyen, Christelle, Palazzo, Clémence, Fayad, Fouad, Revel, Michel, Gregory, Thomas, Poiraudeau, Serge, Roby-Brami, Agnès, Lefèvre-Colau, Marie-Martine
• Format: Article
• Language: English
• Subjects: 3D kinematics; Aged; Aged, 80 and over; Arthroplasty, Replacement, Shoulder - methods; Biomechanical Phenomena - physiology; Biomechanics; Cross-Sectional Studies; Engineering Sciences; Female; Human health and pathology; Humans; Life Sciences; Male; Mechanics; Middle Aged; Physical Medicine and Rehabilitation; Range of Motion, Articular - physiology; Rhumatology and musculoskeletal system; Rotation; Scapula; Shoulder - diagnostic imaging; Shoulder - physiopathology; Shoulder - surgery; Tissues and Organs; Total shoulder arthroplasty; Translation
• ISSN: 2468-7812; 2468-7812
• DOI: 10.1016/j.msksp.2017.03.006

Abstract Background The movement of the arm relative to the trunk results from coordinated 3D glenohumeral and scapulothoracic movements. Changes in scapula kinematics may occur after total shoulder arthroplasty and could affect clinical and functional outcomes. Objectives To assess the 3D movement of the scapula during arm elevation after anatomic and reverse total shoulder arthroplasty. Design/Methods This was a single-centre, non-randomized, controlled cross-sectional study. Patients with anatomic (n = 14) and reverse total shoulder arthroplasty (n = 9) were prospectively enrolled and were compared to age-matched asymptomatic controls (n = 23). 3D scapular kinematics were assessed by a non-invasive, electromagnetic method during arm abduction and flexion. 3D scapular rotations and 3D linear displacements of the barycentre (geometrical centre) at rest and at 30°, 60° and 90° arm elevation; as well as scapulohumeral rhythm were analysed. Participant groups were compared using one-way ANOVA and Bonferroni post-hoc testing for normally distributed data, and Mann–Whitney U test for non-normally distributed data. Results/Findings Total range of scapular lateral rotation and barycentre displacement were increased, and scapulohumeral rhythm was reduced, in patients with anatomic and reverse total shoulder arthroplasty compared with age-matched controls; however, the global scapular kinematic pattern was preserved. Conclusion/Interpretation For patients after total shoulder arthroplasty, the increased contribution of the scapula to arm elevation is consistent with a compensatory mechanism for the reduced glenohumeral mobility. The stability of the global scapula kinematic pattern reflects its mechanical and neuromotor strength.