Lumbosacral radiculopathy/Root compression:
Symptoms are from compression of nerve root – L4, L5, S1 and S2. Presenting complaints resemble those of a focal lesion or entrapment of nerve (see below).
Lumbar radiculopathy can occur in those without back pain, but usually have back pain with radiation below the knee. Most common causes are disc herniations/ruptures, osteoarthritis, congenital deformities of spine, trauma, postural problems and infections.
Pain is characteristically in back and dermatome distribution; usually precipitated by movement of spine; increases with a Valsalva manoeuvre or straight leg raise; range of motion is restricted; relief of pain when lying down is common; lumbar lordosis; tenderness on palpation of nerve root
Ventral or motor root involvement weakness and atrophy of muscles
Dorsal or sensory root involvement sensory impairment in dermatomal distribution
Usually asymmetric muscle weakness with atrophy and fasciculations – weakness is confined to myotomal distribution – sensory loss in dermatomal distribution.
Tone is normal or decreased; hyporeflexia
L3-L4 quadriceps weakness; knee jerk reflex lost; parathesia in lower leg; anterior thigh pain
L5 weakness of foot dorsiflexion; parathesias on anterior and lateral aspect of leg and dorsum of foot (rarely presents as a foot drop); pain on dorsal foot, lateral calf, posterolateral thigh and buttocks
S1 weakness of foot plantarflexion; ankle jerk reflex lost; parathesias on sole of foot and lateral aspect of foot and ankle; plantar heel/foot pain; pain also in posterior calf, posterior thigh and buttocks
S2 weakness of plantarflexion; ankle jerk depressed; parathesia on posterior leg
Finsterbush et a l (1983) using a sensitive measure of for strength of the extensor hallucis longus, showed a weakness in this muscle with discogenic lesions in the lower lumbar region. They recommended measurement of the strength of this muscle as a screening test for discogenic lesions.
Rest; immobilisation; NSAID’s; physiotherapy