Tanya Anne Mackenzie1, Lee Herrington2, Lenard Funk3, Ian Horsley4, Ann Cools5. 1. Salford University, Health, Sports and Rehabilitation Sciences, Manchester, M5 4WT, United Kingdom. Electronic address: t.a.mackenzie@edu.salford.ac.uk. 2. Salford University, School of Sport, Exercise and Physiotherapy, Salford, Manchester, United Kingdom. Electronic address: l.c.herrington@salford.ac.uk. 3. University of Salford, Salford, M6 6PU, United Kingdom. Electronic address: lenfunk@shoulderdoc.co.uk. 4. English Institute of Sport, United Kingdom. Electronic address: Ian.Horsley@eis2win.co.uk. 5. Ghent University, Dept of Rehabilitation Science and Physiotherapy, Belgium. Electronic address: anncools@ugent.be.
Abstract
BACKGROUND: Maintenance of the subacromial space is important in impingement syndromes. Research exploring the correlation between biomechanical factors and the subacromial space would be beneficial. OBJECTIVES: To establish if relationship exists between the independent variables of scapular rotation, shoulder internal rotation, shoulder external rotation, total arc of shoulder rotation, pectoralis minor length, thoracic curve, and shoulder activity level with the dependant variables: AHD in neutral, AHD in 60° arm abduction, and percentage reduction in AHD. DESIGN: Controlled laboratory study. METHOD: Data from 72 male control shoulders (24.28years STD 6.81 years) and 186 elite sportsmen's shoulders (25.19 STD 5.17 years) were included in the analysis. The independent variables were quantified and real time ultrasound was used to measure the dependant variable acromio-humeral distance. RESULTS: Shoulder internal rotation and pectoralis minor length, explained 8% and 6% respectively of variance in acromio-humeral distance in neutral. Pectoralis minor length accounted for 4% of variance in 60° arm abduction. Total arc of rotation, shoulder external rotation range, and shoulder activity levels explained 9%, 15%, and 16%-29% of variance respectively in percentage reduction in acromio-humeral distance during arm abduction to 60°. CONCLUSION: Pectorals minor length, shoulder rotation ranges, total arc of shoulder rotation, and shoulder activity levels were found to have weak to moderate relationships with acromio-humeral distance. Existence and strength of relationship was population specific and dependent on arm position. Relationships only accounted for small variances in AHD indicating that in addition to these factors there are other factors involved in determining AHD.
BACKGROUND: Maintenance of the subacromial space is important in impingement syndromes. Research exploring the correlation between biomechanical factors and the subacromial space would be beneficial. OBJECTIVES: To establish if relationship exists between the independent variables of scapular rotation, shoulder internal rotation, shoulder external rotation, total arc of shoulder rotation, pectoralis minor length, thoracic curve, and shoulder activity level with the dependant variables: AHD in neutral, AHD in 60° arm abduction, and percentage reduction in AHD. DESIGN: Controlled laboratory study. METHOD: Data from 72 male control shoulders (24.28years STD 6.81 years) and 186 elite sportsmen's shoulders (25.19 STD 5.17 years) were included in the analysis. The independent variables were quantified and real time ultrasound was used to measure the dependant variable acromio-humeral distance. RESULTS: Shoulder internal rotation and pectoralis minor length, explained 8% and 6% respectively of variance in acromio-humeral distance in neutral. Pectoralis minor length accounted for 4% of variance in 60° arm abduction. Total arc of rotation, shoulder external rotation range, and shoulder activity levels explained 9%, 15%, and 16%-29% of variance respectively in percentage reduction in acromio-humeral distance during arm abduction to 60°. CONCLUSION: Pectorals minor length, shoulder rotation ranges, total arc of shoulder rotation, and shoulder activity levels were found to have weak to moderate relationships with acromio-humeral distance. Existence and strength of relationship was population specific and dependent on arm position. Relationships only accounted for small variances in AHD indicating that in addition to these factors there are other factors involved in determining AHD.
Authors: Santiago Navarro-Ledesma; Manuel Fernandez-Sanchez; Filip Struyf; Javier Martinez-Calderon; Jose Miguel Morales-Asencio; Alejandro Luque-Suarez Journal: BMJ Open Date: 2019-06-12 Impact factor: 2.692
Authors: Fernanda B Charry; María Jesús L Martínez; Liliana Rozo; Fernando Jurgensen; Juan Guerrero-Henriquez Journal: J Man Manip Ther Date: 2021-07-14