Observational study in healthy subjects, to learn more about patients with rotator cuff disease.
Conditions
Interventions
Subjects will be seated, having their dominant arm fixed in a splint. Next, subjects will have to exert isometric forces in directions perpendicular to the long axis of the humerus, using visual feedb
Sponsors
Leiden University Medical Center
Eligibility
Inclusion criteria
Inclusion criteria: 1. Age: between 18 and 60 y.o.; 2. No history of shoulder complaints; 3. No current complaints of the shoulder.
Exclusion criteria
Exclusion criteria: 1. No signed informed consent; 2. Pace-maker or other electronic implants.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| External force controlled Electromyography (EMG). To measure activation of individual shoulder muscles (in particular: deltoids, supraspinate, infraspinate, pectoralis major, upper and lower trapezius, latissimus dorsi and teres major) and analyze for relative changes in activation of rotator cuff and deltoid muscles with increased arm moment loading. Conditions: Arm against an external force in 24 directions (humerus fixed in splint, constant exerted abduction force), 2 moment arms (~4 cm and ~29 cm from the glenohumeral joint). Outcome: Average filtered EMG value (rEMG), principal Action (PA), Activation Ratio (AR) and Max Voluntary Force (MVF), relative change in deltoid and supraspinate activation (rEMG) expressed in percentages. | — |
Secondary
| Measure | Time frame |
|---|---|
| 3D-Motion tracking of the scapular position during arm force task with the humerus in a fixed position. To record 3D kinematics of the scapula with a motion tracking system for analyzing the eventual change in scapular position as a result from changes in muscle activations when altering moment loading (with a constant force). Conditions: Arm against an external force (humerus fixed in a splint, constant exerted force), 2 moment arms (~4 cm and ~29 cm from the glenohumeral joint). Outcome: 3D scapular positions (scapular posterior tilting, external rotation, and lateral rotation as described in literature) with altering moments and muscle activations. | — |
Contacts
Public ContactP.B. Witte, de
PO Box 9600, postzone J-11-R
Outcome results
None listed