The Straight leg raise also, called Lasègue's sign or Lasègue test, 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 (fifth lumbar spinal nerve), S1 (the first sacral spinal nerve) or S2 (the second sacral spinal nerve).

[edit] Technique

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.

A variation is to lift the leg while the patient is sitting.^[1] However, this reduces the sensitivity of the test.^[2]

[edit] Interpretation

"The straight leg raise test is positive if pain in the sciatic distribution is reproduced at less than 30 degrees passive flexion of the straight leg." ^[3]

A meta-analysis reported the accuracy as^[4]:

• sensitivity 91%
• specificity 26%

If raising the opposite leg causes pain (cross straight leg raising):

• sensitivity 29%
• specificity 88%

[edit] References

1. ^ Waddell G, McCulloch JA, Kummel E, Venner RM (1980). "Nonorganic physical signs in low-back pain". Spine 5 (2): 117–25. doi:10.1097/00007632-198003000-00005. PMID 6446157. 
2. ^ Rabin A, Gerszten PC, Karausky P, Bunker CH, Potter DM, Welch WC (2007). "The sensitivity of the seated straight-leg raise test compared with the supine straight-leg raise test in patients presenting with magnetic resonance imaging evidence of lumbar nerve root compression". Archives of physical medicine and rehabilitation 88 (7): 840–3. doi:10.1016/j.apmr.2007.04.016. PMID 17601462. 
3. ^ Speed C (2004). "Low back pain". BMJ 328 (7448): 1119–21. doi:10.1136/bmj.328.7448.1119. PMID 15130982. 
4. ^ Devillé WL, van der Windt DA, Dzaferagić A, Bezemer PD, Bouter LM (2000). "The test of Lasègue: systematic review of the accuracy in diagnosing herniated discs". Spine 25 (9): 1140–7. doi:10.1097/00007632-200005010-00016. PMID 10788860.