Anterior Drawer test of the shoulder considered positive in these situation:
The relative motion between the immobilized scapula and the anteriorly displaced humerus is a measure of anterior instability and can be specified in degrees.
Occasional audible clicking with or without pain can indicate an anterior labral defect.
Sensitivity & Specificity
A study by Adam J Farber 1 for a clinical assessment of three common tests for traumatic anterior shoulder instability (apprehension test, relocation test and anterior drawer test), he found that anterior drawer test (when pain does not prevent it from being performed) is helpful for diagnosing traumatic anterior instability. The accuracy was as following:
Sensitivity: 53 %
Specificity: 85 %
Anterior instability of the G-H joint is the most common direction of instability.
Repetitive overhead activities such as throwing can lead to microtrauma at the shoulder, leading to eventual breakdown of both the static and dynamic stabilizers of the joint, or G-H instability.
The mechanism for an anterior dislocation is abduction, external rotation, and extension and is common in throwing and racquet sports, gymnastics, and swimming.
Following an acute trauma, the patient typically complains of severe pain and a sense that the shoulder is out.
The humeral head will be palpable anteriorly and the posterior shoulder will exhibit a hollow beneath the acromion.
In younger age groups (approximately 25 years and younger), the chance of recurrent anterior dislocation after the initial event is greater than 95% 2.
Recurrences are rare in patients older than 50 years of age 3.
When anterior instability is suspected, the clinician should assess for tightness of the posterior capsule. Posterior capsule tightness has been shown to accentuate anterior translation and superior migration.361 Loss of IR in young patients may be an important finding suggestive of posterior capsular contracture that is often associated with subtle instability. The posterior joint glide is also restricted.
Symptoms also include varying degrees of instability, transient neurologic symptoms, and easy fatigability. Warner et al.4 reported a lower IR to-ER ratio for peak torque and total work in the dominant shoulder of patients with instability as compared with healthy controls. This suggests that an association exists between relative IR weakness and anterior instability.
Farber AJ, Castillo R, Clough M, Bahk M, McFarland EG. Clinical assessment of three common tests for traumatic anterior shoulder instability. J Bone Joint Surg Am. 2006;88(7):1467-1474. doi:10.2106/JBJS.E.00594. PMID: 16818971.
Hovelius L, Eriksson K, Fredin H, et al: Recurrences after initial dislocation of the shoulder. J Bone Joint Surg [Am] 65:343–349, 1983.
Rowe CR, Sakellarides HT: Factors related to recurrences of anterior dislocations of the shoulder. Clin Orthop 20:40, 1961.
Warner JJP, Micheli LJ, Arslanian LE, et al: Patterns of flexibility, laxity, and strength in normal shoulders and shoulders with instability and impingement. Am J Sports Med 18:366–375, 1990.
Clinical Tests for the Musculoskeletal System 3rd Edition.
Dutton’s Orthopaedic Examination, Evaluation, And Intervention 3rd Edition.