Sulcus Sign Test [Inferior Shoulder Instability] | Rationale & Interpretation

What is the primary action performed by the physical therapist during the sulcus sign test?

• Rotating the humerus medially

• Applying an inferior directed longitudinal distraction force

• Applying a superior force on the humerus

• Stabilizing the scapula with both hands

What indicates a positive sulcus sign test?

• No visible sulcus

• A sulcus less than 1 centimeter

• A sulcus exactly 1 centimeter

• A sulcus greater than 2 centimeters

Which of the following is NOT a reason for a sulcus sign?

• Laxity of the superior glenohumeral ligament

• Laxity of the coracohumeral ligament

• Tightness of the deltoid muscle

• Inferior instability of the humerus

What is the specificity of the sulcus sign test when the sulcus is greater than 2 centimeters?

• 50%

• 28%

• 97%

• 75%

Why can't a negative sulcus sign test rule out instability?

• Because the test is too complex

• Because the test is not sensitive

• Because the test is not specific

• Because the test is not reliable