The study is to investigate the dose-response relationship between load-induced muscle activation (liMA) and load-induced glenohumeral translation (liTr) in patients with rotator cuff tears and asymptomatic control subjects. Furthermore the study is to investigate the in vivo dose-response relationship between additional weight and glenohumeral translation, to understand the biological variation in liTr, the influence of disease pathology on the liTr, the potential compensation by muscle activation and muscle size, and the influence of liTr on patient outcomes.
This project is to test the overall hypothesis that rotator cuff tear affects glenohumeral translation and that this functional instability depends on additional load applied, on anatomical and morphological variations, and on type and severity of the injury. The study is to investigate the dose-response relationship between load-induced muscle activation (liMA) and load-induced glenohumeral translation (liTr) in patients with rotator cuff tears and asymptomatic control subjects. Furthermore the study is to investigate the in vivo dose-response relationship between additional weight and glenohumeral translation, to understand the biological variation in liTr, the influence of disease pathology on the liTr, the potential compensation by muscle activation and muscle size, and the influence of liTr on patient outcomes. This study entails cross-sectional experimental multimodal (clinical, biomechanical, radiological) data collection with multiple conditions and a control group.
Study Type
INTERVENTIONAL
Allocation
NON_RANDOMIZED
Purpose
DIAGNOSTIC
Masking
NONE
Enrollment
75
30° arm abduction in the scapular plane will be performed with and without a handheld weight of 1, 2, 3, and 4 kg. All movements will be done bilaterally. Electromyographic (EMG) data of arm and trunk muscles will be recorded using surface electrodes. Participants will be asked to perform full arm abduction with different rotations (internal, neutral and external rotation), flexion and internal-/external rotations movements (without additional handheld weight).
isometric shoulder strength for abduction and internal/external rotation will be assessed with a isometric shoulder strength for abduction and internal/external rotation will be assessed with a dynamometer
Department of Orthopaedics and Traumatology, University Hospital Basel
Basel, Switzerland
Disabilities of arm, shoulder and hand (Quick DASH) questionnaire
30-item questionnaire that looks at the ability of a patient to perform certain upper extremity activities. This questionnaire is a self-report questionnaire that patients can rate difficulty and interference with daily life on a 5 point Likert scale (1 being no difficulty, 5 being unable).
Time frame: at baseline (approximate duration for all questionnaires: 20 minutes)
Constant Score
The Constant-Murley score (CMS) is a 100-points scale composed of a number of individual parameters. These parameters define the level of pain and the ability to carry out the normal daily activities of the patient. The test is divided into four subscales: pain (15 points), activities of daily living (20 points), strength (25 points) and range of motion: forward elevation, external rotation, abduction and internal rotation of the shoulder (40 points). The higher the score, the higher the quality of the function.
Time frame: at baseline (approximate duration for all questionnaires: 20 minutes)
American Shoulder and Elbow Surgeons (ASES) Shoulder Score
The American Shoulder and Elbow Surgeons Shoulder Score (ASES) is a mixed outcome reporting measure, applicable for use in all patients with shoulder pathology regardless of their specific diagnosis. The ASES questionnaire is composed of both a physician-rated component and a patient-reported component. The patient questions focus on joint pain, instability, and activities of daily living. The pain and functional portions are summed to obtain the final ASES score with higher scores indicating better outcomes.
Time frame: at baseline (approximate duration for all questionnaires: 20 minutes)
Subjective Shoulder Value (SSV)
The SSV is defined as a patient's subjective shoulder assessment expressed as a percentage of an entirely normal shoulder, which would score 100%.
Time frame: at baseline (approximate duration for all questionnaires: 20 minutes)
numerical pain rating scale (NRS) score
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fluoroscopic images (Multitom Rax, Siemens Healthineers, Erlangen, Germany) of each shoulder will be taken during the 30° arm abduction test with and without a handheld weight (0, 2, and 4kg)
MRI of both shoulders will be taken
data collection by health questionnaires
The Numeric Pain Rating Scale (NPRS) is a unidimensional measure of pain intensity in adults (from 0-10: "0" = no pain. "10" = the most intense pain imaginable)
Time frame: at baseline (approximate duration for all questionnaires: 20 minutes)
Loaded shoulder abduction test with motion analysis
The subject will lift their arm to 30° shoulder abduction in the scapular plane, data will be captured holding 0, 1, 2, 3, and 4 kg, respectively, in their hand. Reflective surface markers will be placed bilaterally on the participants' trunk and arms. Position of these markers will be recorded using infrared cameras that only record the reflections of the markers. Additionally, inertial sensors will be positioned on the subjects' thorax, scapulae, humeri and forearms.
Time frame: at baseline (approximate duration for motion analysis: 50 minutes)
Loaded shoulder abduction test with single plane fluoroscopic images
fluoroscopic images (Multitom Rax, Siemens Healthineers, Erlangen, Germany) of each shoulder will be taken during the 30° arm abduction test with and without a handheld weight (0, 2, and 4kg)
Time frame: at baseline (approximate duration for motion analysis: 50 minutes).
Load-induced muscle activity from electromyography (EMG)
During arm movements in the loaded shoulder test and muscle strength tests, muscle activation of the infraspinatus, biceps brachii, anterior, middle and posterior part of the deltoid, clavicular part of the pectoralis major, latissimus dorsi and the upper part of the trapezius will be measured bilaterally using a 16-channel EMG system
Time frame: at baseline (approximate duration for motion analysis: 50 minutes)
Glenohumeral translation from single plane fluoroscopy
the vertical distance of the glenohumeral joint centre (GHJC) and the radiopaque acromion marker will be measured. Fluoroscopy (FL) based liTr will be calculated for each participant as the slope of the regression of the negative GHJC to acromion distance measurements on the load magnitude.
Time frame: at baseline (approximate duration for motion analysis: 50 minutes)
Glenohumeral translation from instrumented motion analysis
The vertical distance of the GHJC to the acromion marker will be calculated for a neutral trial and with the arm in 30° shoulder abduction for each loading condition. Motion analysis (MA) based liTr will be calculated for each participant as the slope of the regression of the negative GHJC to acromion distance measurements on the load magnitude
Time frame: at baseline (approximate duration for motion analysis: 50 minutes)
Critical shoulder angle (CSA)
Subject's CSA will be measured on an anterior-posterior double-obliquity fluoroscopy image of the shoulder as the angle subtended by a line parallel to the glenoid and a line through the inferior-lateral edge of the glenoid and the inferior-lateral edge of the acromion. The CSA is reproducible and significantly greater in patients with rotator cuff tears than the general population. High angles (\>35°-38°) have been associated with rotator cuff tears and greater joint instability.
Time frame: at baseline (approximate duration for motion analysis: 50 minutes)
Glenoid inclination (GI)
GI will be measured on the fluoroscopy image as the angle between a line from the upper to the lower glenoid rim (glenoid plane) and a second line set on the floor of the supraspinous fossa. Abnormal GI might be associated with rotator cuff tears and superior humeral head migration.
Time frame: at baseline (approximate duration for motion analysis: 50 minutes)
Greater tuberosity angle (GTA)
GTA will be measured as the angle between a line parallel to the humerus diaphysis through the GHJC and a line from the upper border of the humeral head to the most superolateral edge of the greater tuberosity. A GTA of more than 70° has been observed to predict rotator cuff tear.
Time frame: at baseline (approximate duration for motion analysis: 50 minutes)
Muscle cross sectional area (MCSA)
The MCSA of all rotator cuff muscles will be measured at two different positions on parasagittal reformatted images. MCSA of the deltoid will also be measured on the axial plane at the middle of the glenoid.
Time frame: at baseline (approximate duration is approximately 1 hour and 15 minutes)
Tear size retrieved from MR images
Tear size will be classified into partial (1) or complete supraspinatus muscle tear (2).
Time frame: at baseline (approximate duration is approximately 1 hour and 15 minutes)
Tear type retrieved from MR images
Tear type will be classified into supraspinatus tear without injury to other rotator cuff muscles (type A) and with injury to other rotator cuff muscles (type B). Both will be used as indicators for injury severity
Time frame: at baseline (approximate duration is approximately 1 hour and 15 minutes)
Isometric shoulder muscle strength for abduction and internal/external rotation
Shoulder muscle strength will be tested under isometric conditions using a dynamometer. The maximum of 3 trials will be calculated and recorded as the participant's maximum isometric strength.
Time frame: at baseline (approximate duration: 40 minutes).