Slr is a neurodynamic test, which is passively done.
Also it is neural tissue test.
Called the Lasègue’s test as well.
Used to determine and rule out problems like lower back pain, disc herniation, sciatica , hamstring tightness and leg stiffness.
Technique for performing SLR ?
Tell the patient to lay down in supine position.
Without any pillow or any kind of support .
Then the therapist will hold the patient leg at ankle joint .
Move the leg passively.
Remember, the hip will be slight medially rotated and adducted as well.
Knee has to be kept in extended position.
Clincal Findings from SLR test?
Nuerological pain will be arrived , in leg due to lumbar disc herniation or bulging , at 30-70° of hip flexion.
At less than 30° of hip Flexion may indicate gluteal abscess, tumour at gluteal, acute dural inflammation.
When flexed more than 70° , it is mainly 2 things , hamstring tightness and SIJ joint dysfunction.
Increasing symptoms in SLR ?
Including neck flexion in SLR, is called the Hyndman’s Sign .
Ankle dorsiflexion included is called the Bragard’s Sign .
Great toe extension in SLR ( instead of ankle dorsiflexion ) is documented as Sicard’s test.
Modification of SLR test ?
When performing SLR , when the foot is inverted ,Sural nerve is involved. When performing SLR , when the foot is everted , tibial nerve is involved.
Specificity and sensitivity of SLR ?
Specificity of this SLR is found to be 0.26 or 26 % .
And Sensitivity of this SLR test is found to be 0.91 or 91% .
What is Crossed SLR test?
This is done to find disc herniation at lumbar spine .
When the contralateral side of hip is flexed , while keeping knee is in extension position, pain will start increasing in contralateral side .
The pathophysiology behind is that dura mater of spinal cord will stretch.
Thus it will cause pain, in the contralateral side of pain .The hip flexed upto 40° , the pain will start shooting.It is the same SLR performed , but in contralateral leg. Its specificity is high and sensitivity is low.
Deville W, van der Windt D, Dzaferagic A, et al. “The test of Lasegue. Systematic review of the accuracy in diagnosing herniated discs.” Spine 200; 25: 1140-1147.