Shoulder Posterior Stress Test

Posterior Stress Test (or Posterior Apprehension test) of the shoulder is used to test for Posterior Instability.

How to perform Shoulder Posterior Stress Test?

• The patient in supine position.
• Place the patient’s arm in flexion, adduction, and internal rotation and apply a posteriorly directed force.

What does a positive Posterior Apprehension test mean?

Posterior Apprehension test is positive if there is pain and sense of instability with the maneuver.

Notes

The most characteristic sign for a shoulder posterior dislocation is a loud clunk as the shoulder is moved from a forward flexed position into abduction and external rotation, a positive finding that is often misdiagnosed as an anterior dislocation.

The findings for a posterior dislocation are usually severe pain, limited ER, often to less than 0 degree, and limited elevation to less than 90 degrees.

Patients who have a posterior instability pattern typically report symptoms with the arm in a forward flexed, adducted position, such as when pushing open heavy doors.

There is usually a posterior prominence and rounding of the shoulder as compared to the opposite side, and a flattening of the anterior aspects of the shoulder. Looking down at the patient’s shoulders from behind can best assess these asymmetries.

Reference

1. Rockwood and FA . The shoulder. Philadelphia: Saunders; 1990. Matsen III. Glenohumeral instability. pp. 611–755.
2. María Valencia Mora, Miguel Ángel Ruiz Ibán, Jorge Diaz Heredia, Juan Carlos Gutiérrez-Gómez, Raquel Ruiz Diaz, Mikel Aramberri, and Carlos Cobiella. Physical Exam and Evaluation of the Unstable Shoulder. Open Orthop J. 2017; 11: 946–956. PMID: 29114336.
3. Clinical Tests for the Musculoskeletal System, Third Edition.
4. Millers Review of Orthopaedics, 7th Edition.