I. Technique

  1. Perform in two positions
    1. Supine Low Back Exam
    2. Sitting Low Back Exam
  2. Discrepancy between 2 positions suggests Malingering
  3. Flex hip from 180 to 90 degrees

II. Interpretation: Criteria for positive test

  1. Sciatic Pain at 30 to 70 degrees
  2. Aggravation of pain dorsiflexion of the foot
  3. Relief of pain by knee flexion

III. Interpretation: What patient experiences

  1. Radiating pain into the legs
    1. Suggests radiculopathy
    2. Higher likelihood findings suggesting radiculopathy
      1. Excruciating Sciatica-like pain
      2. Pain occurs at 30 to 40 degrees of leg elevation
  2. Pain radiates into opposite leg (Crossed Straight Leg Raise)
    1. Indicates severe impingement
    2. Almost always due to a large disk Herniation

IV. Modifications: Lasegue's Test

  1. Dorsiflex foot while performing Straight Leg Raise

V. Efficacy: Predicting Lumbar Disc Herniation

  1. Straight Leg Raise
    1. Test Sensitivity: Up to 98%
    2. Test Specificity: Up to 61%
    3. Negative Likelihood Ratio: 0.2 (high Negative Predictive Value)
  2. Crossed Straight Leg Raise
    1. Test Sensitivity: Up to 43%
    2. Test Specificity: Up to 98%
    3. Positive Likelihood Ratio: 4.3 (high Positive Predictive Value)

Images: Related links to external sites (from Google)