Shield Test (Release Test) for Anterior Shoulder Instability
The shield test, also known as the release test or surprise test, is indicated for patients with suspected traumatic anterior shoulder instability, particularly those with a history of anterior shoulder dislocation or recurrent subluxation episodes. 1, 2
Primary Indications
Young patients (<35 years) with history of traumatic anterior shoulder dislocation are the primary population for this test, as they have the highest risk of recurrent instability and labroligamentous injury 3
Patients presenting with suspected anterior glenohumeral instability who need clinical confirmation before proceeding to advanced imaging 1, 2
Individuals with sudden onset of shoulder complaints following trauma, as this history combined with a positive release test strongly predicts anterior instability 2
Diagnostic Performance
The release test demonstrates the best sensitivity and specificity among all clinical tests for anterior shoulder instability, making it the most reliable physical examination maneuver for this condition 1
When combined with patient age, history of previous dislocation, and sudden onset of complaints, the release test achieves excellent diagnostic accuracy (AUC 0.95) 2
The test provides an overall accuracy of 80.5% to 86.4% for diagnosing traumatic anterior instability 2
Clinical Context and Testing Algorithm
Perform the shield test as part of a focused examination battery that includes:
Apprehension test first (72% sensitivity, 96% specificity when using apprehension as the criterion) 4
Relocation test second (81% sensitivity, 92% specificity) 4
Release/shield test third as the most specific confirmatory maneuver 1, 2
Consider anterior drawer test if pain does not prevent examination (53% sensitivity, 85% specificity when reproduction of instability symptoms is the criterion) 4
Patient Selection Priorities
Highest yield in patients aged 16-40 years with first-time or recurrent traumatic anterior dislocation 3, 5
Essential for evaluating recurrent instability risk in young athletic populations where the combination of history and positive release test optimizes diagnostic accuracy 1
Particularly valuable in older patients (>40 years) to differentiate instability from rotator cuff pathology, though associated rotator cuff tears must not be overlooked 3, 6
Critical Caveats
Never rely on the shield test alone—it must be combined with proper radiographic evaluation including AP views in internal and external rotation PLUS axillary or scapula-Y view before any treatment decisions 3, 7
Pain during examination may limit test performance, particularly with the anterior drawer test which cannot be completed in 13% of patients due to discomfort 4
A negative shield test does not rule out instability—if clinical suspicion remains high based on age and history, proceed to MR arthrography (gold standard for labral tears with 86-100% sensitivity) 6