Posterior Shear Test for Lumbar Instability | Rationale & Interpretation

The video tutorial explains the posterior lumbar shear test, a method to assess posterior lumbar instability. It details the positioning of the patient and the physical therapist's hands, emphasizing the stabilization of L5 and palpation of L4. The tutorial guides on instructing the patient to protract their scapulas to detect any excessive posterior movement of L4 relative to L5, indicating instability. The video also contrasts this with the anterior shear test and describes the expected sensations during a positive test.

What is the primary purpose of the shear test discussed in the video?

• To measure hip flexion range

• To evaluate posterior lumbar instability

• To assess anterior lumbar instability

• To test knee joint stability

During the shear test, where should the caudal hand be placed?

• On the L4 spinous process

• On the L5 spinous process

• On the patient's ASIS

• On the L3 spinous process

What is the role of the cranial hand in the posterior shear test?

• To stabilize L5 firmly

• To palpate L4 loosely

• To apply force on the patient's ASIS

• To detect movement of L5

What should the patient do with their scapulas during the test?

• Retract them forcefully

• Protract them lightly

• Elevate them

• Keep them neutral

Why is it important for the PT to maintain their position during scapular protraction?

• To ensure the test remains balanced and isometric

• To allow the patient to move freely

• To increase the force applied to the ASIS

• To prevent the patient from falling

What indicates a positive posterior shear test?

• No movement of L4 relative to L5

• Movement of L5 relative to L4

• No significant movement detected

• Excessive posterior translation of L4 relative to L5

In the event of a positive test, which vertebra moves excessively?

• L2 moves superiorly

• L4 moves posteriorly

• L3 moves laterally

• L5 moves anteriorly