Prone Instability Test

Special Test

Assesses lumbar instability.

Purpose

Screen for Prone Instability findings.

Execution

1. Lie prone with the trunk on a table and feet on the floor
2. Apply posterior-to-anterior pressure to the lumbar spine
3. Have the client lift the legs off the floor
4. Reapply pressure to the lumbar spine
5. Compare symptoms between positions

Key Observations

• Pain that improves with extensor activation
• Suggests segmental instability

Views

• posterior

Protocol

1. Observe from: posterior.
2. Standardize start position and instructions.
3. Perform 2-3 trials per side when applicable.
4. Record key observations and any positive indicators.
5. Compare left vs right when applicable.

Reference

David J. Magee