Reverse Shoulder Prosthesis Study

Study Overview
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Brief Summary
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The objective of this clinical study is to evaluate the safety and efficacy of the Encore Reverse Shoulder Prosthesis (RSP). The clinical results of the RSP will be compared to clinical results published in literature for rotator cuff arthropathy and salvage procedures.

Official Title
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Encore Reverse Shoulder Prosthesis

Conditions
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Rotator Cuff Arthropathy, Failed Total Shoulder, Failed Hemi-arthroplasty

Intervention / Treatment
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* Device: Reverse Shoulder Prosthesis
* Device: Reverse Shoulder Prosthesis


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Irreparable rotator cuff or failed hemi or total shoulder arthroplasty with irreparable rotator cuff Evidence of upward displacement of the humeral head with respect to the glenoid Loss of glenohumeral joint space Functional deltoid muscle Patient is likely to be available for evaluation for the duration of the study Visual Analog Pain Scale 5 or greater Exclusion Criteria: Non functional deltoid muscle Active sepsis Excessive glenoid bone loss Pregnancy Neurological abnormalities, which could hinder patient's ability or willingness to follow study procedures. For example, any that may restrict physical activities such as Parkinson's, Multiple Sclerosis, or previous stroke, which affects upper extremity. Mental conditions that may interfere with ability to give an informed consent or willingness to fulfill the study requirements (i.e., severe mental retardation such that the patient cannot understand the informed consent process, global dementia, prior strokes that interfere with the patient's cognitive abilities, senile dementia, and Alzheimer's Disease. Prisoners Conditions that place excessive demand on the implant (i.e. Charcot's joints, muscle deficiencies, refusal to modify postoperative physical activities, skeletal immaturity). Known metal allergy (i.e., jewelry). Visual Analog Pain Scale <5.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Primary<br>Primary shoulder | Device: Reverse Shoulder Prosthesis<br>* For subjects with rotator cuff arthropathy and no previous shoulder device implanted.<br>|
| Experimental: Revision<br>Revision shoulder | Device: Reverse Shoulder Prosthesis<br>* For subjects with rotator cuff arthropathy and a failed hemi or total shoulder implant.<br>|
| Experimental: Continued Access<br>Primary shoulder subjects enrolled at a later date in order to collect more data. | Device: Reverse Shoulder Prosthesis<br>* For subjects with rotator cuff arthropathy and no previous shoulder device implanted.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| American Shoulder and Elbow Surgeons Shoulder Score | The patient self-report section of the ASES is a condition specific scale which is intended to measure functional limitations and pain of the shoulder. On a scale of 0 to 100, the use of their shoulder is measured with 0 = no use and 100 = full use. The assessment is done in two sections. One Pain (measured by the Visual Analog Pain Scale) and the second is a list of 10 questions referred to as the Activities of Daily Living. The results are calculated with the following equation: [(10 - Visual analog scale pain score) x 5] + [(5/3) x Cumulative ADL score] | 2-year | 
| Average Range of Motion | Physician's assessment of a subject's range of motion in degrees. | 2-year | 
| Subject Satisfaction With Surgery | Each subject had a chance to rate their satisfaction with surgery at each study interval. | 2-year | 
| Have Surgery Again? | Subject satisfaction: subject's willingness to have surgery performed again if necessary. | 2-year | 
| Neer's Limited Goals | To meet Neer's limited goals, a subject must report: none, slight or moderate pain with unusual activity and exhibit >90 degrees active forward elevation and exhibit >20 degrees of active external rotation. | 2-year | 
| Radiographic Failures | Radiographic failure is defined as a shift in the position of the component >3mm or 3 degrees, a fracture of the cement mantle, a fracture of the component, or a >2mm radiolucency completely around either prosthesis. | Post-operative, 3-month, 6-month, 1-year, 2-year | 
| Safety Assessment | Number of device related adverse events and device failures at the 2 year time frame. | 2-year |