Arjen Kolk1, Pieter Bas de Witte2, Jan Ferdinand Henseler2, Erik W van Zwet3, Ewoud R A van Arkel4, Peer van der Zwaal4, Rob G H H Nelissen5, Jurriaan H de Groot6. 1. Department of Orthopaedics, Leiden University Medical Center, Leiden, The Netherlands; Laboratory for Kinematics and Neuromechanics, Department of Orthopaedics and Rehabilitation, Leiden University Medical Center, Leiden, The Netherlands. Electronic address: a.kolk@lumc.nl. 2. Department of Orthopaedics, Leiden University Medical Center, Leiden, The Netherlands; Laboratory for Kinematics and Neuromechanics, Department of Orthopaedics and Rehabilitation, Leiden University Medical Center, Leiden, The Netherlands. 3. Department of Medical Statistics and Bioinformatics, Leiden University Medical Center, Leiden, The Netherlands. 4. Department of Orthopaedic Surgery, Medical Center Haaglanden, The Hague, The Netherlands. 5. Department of Orthopaedics, Leiden University Medical Center, Leiden, The Netherlands. 6. Laboratory for Kinematics and Neuromechanics, Department of Orthopaedics and Rehabilitation, Leiden University Medical Center, Leiden, The Netherlands.
Abstract
BACKGROUND: Patients with a rotator cuff (RC) tear often exhibit scapular dyskinesia with increased scapular lateral rotation and decreased glenohumeral elevation with arm abduction. We hypothesized that in patients with an RC tear, scapular lateral rotation, and thus glenohumeral elevation, will be restored to normal after RC repair. METHODS: Shoulder kinematics were quantitatively analyzed in 26 patients with an electromagnetic tracking device (Flock of Birds) before and 1 year after RC repair in this observational case series. We focused on humeral range of motion and scapular kinematics during abduction. The asymptomatic contralateral shoulder was used as the control. Changes in scapular kinematics were associated with the gain in range of motion. Shoulder kinematics were analyzed using a linear mixed model. RESULTS: Mean arm abduction and forward flexion improved after surgery by 20° (95% confidence interval [CI], 2.7°-36.5°; P = .025) and 13° (95% CI, 1.2°-36.5°; P = .044), respectively. Kinematic analyses showed decreases in mean scapular protraction (ie, internal rotation) and lateral rotation (ie, upward rotation) during abduction by 3° (95% CI, 0.0°-5.2°; P = .046) and 4° (95% CI, 1.6°-8.4°; P = .042), respectively. Glenohumeral elevation increased by 5° (95% CI, 0.6°-9.7°; P = .028) at 80°. Humeral range of motion increased when scapular lateral rotation decreased and posterior tilt increased. CONCLUSIONS: Scapular kinematics normalize after RC repair toward a symmetrical scapular motion pattern as observed in the asymptomatic contralateral shoulder. The observed changes in scapular kinematics are associated with an increased overall range of motion and suggest restored function of shoulder muscles.
BACKGROUND:Patients with a rotator cuff (RC) tear often exhibit scapular dyskinesia with increased scapular lateral rotation and decreased glenohumeral elevation with arm abduction. We hypothesized that in patients with an RC tear, scapular lateral rotation, and thus glenohumeral elevation, will be restored to normal after RC repair. METHODS: Shoulder kinematics were quantitatively analyzed in 26 patients with an electromagnetic tracking device (Flock of Birds) before and 1 year after RC repair in this observational case series. We focused on humeral range of motion and scapular kinematics during abduction. The asymptomatic contralateral shoulder was used as the control. Changes in scapular kinematics were associated with the gain in range of motion. Shoulder kinematics were analyzed using a linear mixed model. RESULTS: Mean arm abduction and forward flexion improved after surgery by 20° (95% confidence interval [CI], 2.7°-36.5°; P = .025) and 13° (95% CI, 1.2°-36.5°; P = .044), respectively. Kinematic analyses showed decreases in mean scapular protraction (ie, internal rotation) and lateral rotation (ie, upward rotation) during abduction by 3° (95% CI, 0.0°-5.2°; P = .046) and 4° (95% CI, 1.6°-8.4°; P = .042), respectively. Glenohumeral elevation increased by 5° (95% CI, 0.6°-9.7°; P = .028) at 80°. Humeral range of motion increased when scapular lateral rotation decreased and posterior tilt increased. CONCLUSIONS: Scapular kinematics normalize after RC repair toward a symmetrical scapular motion pattern as observed in the asymptomatic contralateral shoulder. The observed changes in scapular kinematics are associated with an increased overall range of motion and suggest restored function of shoulder muscles.
Authors: Nicole G Lemaster; Carolyn M Hettrich; Cale A Jacobs; Nick Heebner; Philip M Westgate; Scott Mair; Justin R Montgomery; Tim L Uhl Journal: Clin Orthop Relat Res Date: 2021-09-01 Impact factor: 4.755
Authors: Umile Giuseppe Longo; Laura Risi Ambrogioni; Alessandra Berton; Vincenzo Candela; Carlo Massaroni; Arianna Carnevale; Giovanna Stelitano; Emiliano Schena; Ara Nazarian; Joseph DeAngelis; Vincenzo Denaro Journal: Int J Environ Res Public Health Date: 2020-04-24 Impact factor: 3.390