Inspect the spine for any developmental or traumatic deformities.
Assess the lumbar lordosis; loss of curvature may indicate ankylosing spondylitis.
Look for any muscle wasting (buttock, thigh, calf).
Check for any discrepancy in leg length by comparing the levels of the iliac crests.
Movement:
Ask the patient to extend the spine, flex forward and then flex laterally by sliding their palm down their outer thigh
Most patients with non-specific back pain will be slightly stiff in extension, have pain on flexion, and asymmetric limitation and pain on lateral flexion.
While Lying Supine
Rule out other joint involvement: check the hip joints for range of movement and pain
Perform stress test on sacro-iliac joints (e.g. FABER test), especially in young patients
Flexion, Abduction, and External Rotation (FABER):
The patient lies in a supine position, and the foot is placed on the opposite knee; in this position groin pain indicates a hip problem rather than a spinal problem
The doctor then presses on the flexed knee and on the opposite anterior superior iliac crest; pain in the sacroiliac area indicates a problem with sacroiliac joints
Test nerve roots:
Straight leg raise test
This stretches nerve roots L4, L5 and S1
Pick the leg up by the ankle
While keeping the knee fully extended, lift the leg up towards ninety degrees
If the patient has significant nerve root entrapment shooting leg pain will be reproduced before you get much beyond thirty degrees of elevation
Back pain produced by straight leg raising is common and does not always indicate nerve root involvement.
Assess muscle power
Muscle group
Nerve Root
Resisted flexion of hip
L2/3
Resisted knee flexion
S2
Resisted dorsiflexion of ankle
L4
Resisted extension of big toe
L5
Resisted plantar flexion of ankle
S1
Check reflexes:
Knee jerk: L3/4
Ankle jerk: L5/S1
Plantar reflex: observe for up-going plantars
Check for skin sensory loss
While Lying Prone
Femoral stretch test (nerve roots L2/3/4)
With the patient lying prone, flex the knee towards ninety degrees
Burning discomfort in the groin or anterior thigh will occur if there is femoral nerve involvement
Palpate the spine for tenderness and for muscle spasm
While on Side
For patients who describe loss of sphincter control test for impaired sensation in the saddle area and assess anal sphincter tone with DRE
