Straight leg raise

The Straight leg raise, also called Lasègue's sign, Lasègue test or Lazarević's sign, is a test done during the physical examination to determine whether a patient with low back pain has an underlying herniated disk, mostly located at L5, With the patient lying down on his/her back on an examination table/or exam floor, the examiner lifts the patient's leg while the knee is straight.

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