Superior Glenohumeral Translation in Patients With Degenerative Rotator Cuff Tears

Study Overview
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Brief Summary
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Degenerative partial and complete rupture of the rotator cuff is a common injury among elder patients. However, the clinical manifestation varies largely with some patients having severe pain and limiting range of motion and others having no complaints. The basic functions of the rotator cuff are to facilitate shoulder motion and stabilization and centering of the glenohumeral joint. The objective of this study is to quantify the difference in superior glenohumeral translation in patients with degenerative rotator cuff tear compared to healthy control subjects and to determine the effect of isolated complete supraspinatus tear and combined complete supraspinatus and either partial infraspinatus or partial subscapularis tear.

Detailed Description
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The study will examine a cohort of 10 patients with isolated complete supraspinatus muscle tear and 10 patients with complete supraspinatus muscle tear and either partial infraspinatus muscle tear or partial subscapularis muscle tear, and a cohort of 10 age-matched healthy control persons. The participants will be recruited from the Clinic of Orthopaedics and Traumatology at the University Hospital Basel. Inclusion criteria: 45 years < age < 65 years; degenerative complete supraspinatus muscle tear or complete supraspinatus muscle tear and either partial infraspinatus muscle tear or partial subscapularis muscle tear; unilateral rotator cuff tear. Exclusion criteria: traumatic tendon ruptures; prior treatment of the ipsilateral upper extremity; clinical history of the contralateral glenohumeral joint; no complete supraspinatus muscle tear; tears in more than two rotator cuff muscles; neuromuscular disorders affecting upper limb movement; additional pathologies that influence the mobility of the shoulder joint; inability to provide informed consent. Patients will complete the health questionnaire and reflective markers and electromyographic sensors will be placed on anatomical landmarks and shoulder muscles, respectively, before loaded and unloaded abduction and flexion arm movements will be performed. Centre of rotation of both shoulders will be calculated to determine glenohumeral translation. This parameter will be compared between patient groups and control subjects using linear mixed models with group membership and load as fixed factor and subject as random factor. The critical shoulder angle will be included as covariate into the model to detect a potential modulating role of this factor on glenohumeral translation.

Official Title
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ROTCUFF - Measuring Load-induced Superior Glenohumeral Translation in Patients With Degenerative Rotator Cuff Tears and Asymptomatic Subjects: 3-dimensional Motion Analysis Versus Single Plane Fluoroscopy

Conditions
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Rotator Cuff Tear or Rupture, Not Specified as Traumatic

Intervention / Treatment
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* Diagnostic Test: Glenohumeral translation assessment


Participation Criteria
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Eligibility Criteria
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Inclusion criteria patients 45 years ≤ age ≤ 65 years Degenerative complete supraspinatus muscle tear or complete supraspinatus muscle tear and either partial infraspinatus muscle tear or partial subscapularis muscle tear Unilateral rotator cuff tear Exclusion criteria patients Traumatic tendon ruptures Incomplete supraspinatus muscle tear Tears in more than two rotator cuff muscles Prior conservative treatment or surgery of the ipsilateral upper extremity Clinical history of the contralateral glenohumeral joint Range of motion < 90° in abduction and flexion Neuromuscular disorders affecting upper limb movement Additional pathologies that influence the mobility of the shoulder joints Inability to provide informed consent Inclusion criteria healthy control subjects • 45 years ≤ age ≤ 65 years

Ages Eligible for Study
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Minimum Age: 45 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Control group<br>age and sex matched healthy control persons | Diagnostic Test: Glenohumeral translation assessment<br>* amount of glenohumeral translation under load<br>|
| isolated tear<br>patients with isolated complete supraspinatus muscle tear | Diagnostic Test: Glenohumeral translation assessment<br>* amount of glenohumeral translation under load<br>|
| combined tear<br>patients with complete supraspinatus muscle tear and either partial infraspinatus muscle tear or partial subscapularis muscle tear | Diagnostic Test: Glenohumeral translation assessment<br>* amount of glenohumeral translation under load<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Glenohumeral translation | Amount of glenohumeral translation under load | Baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Disabilities of arm, shoulder and Hand (DASH) | assessed using the Quick DASH (0 - no problems, 100 - extreme problems) | Baseline | 
| Shoulder function | assessed using the Constant Shoulder Score (0 - no problems, >30 extreme problems) | Baseline | 
| Shoulder pain | assessed using a 15 cm visual analogue scale converted to 0 to 100 scale (0 - no pain; 100 - worst pain imaginable) | Baseline | 
| Critical shoulder angle (CSA) | measured on frontal plane radiographs in neutral arm position available from the clinical consultation. The CSA is the angle between the line connecting the superior with the inferior border of the glenoid fossa and the line connecting the inferior border of the glenoid fossa with the most inferolateral point of the acromion | Baseline | 
| Muscle activity | root mean square of the electromyography (EMG) signal during the arm movements calculated and normalised to the maximal obtained signal intensity | Baseline | 
| Glenohumeral translation from fluoroscopy | the perpendicular distance of the centre of the glenohumeral joint and the x-axis of the scapula coordinate system will be measured. Glenohumeral translation will be defined as the difference in this distance between the abducted arm positions and the resting arm position | Baseline |