Template:Somatic Referred vs Radicular Pain

Somatic Referred vs Radicular Pain

	Somatic Referred	Radicular
Pain quality	Dull, deep ache, or pressure-like	Shooting, lancinating, or electric-shocks
Distribution	Distributed in a wide area, with difficult to perceive boundaries, often demonstrated with an open hand rather than pointing finger. The centres in contrast can be confidently indicated. Fixed in location, commonly in the buttock or proximal thigh. Spread of pain distal to the knee can occur when severe, and it can skip regions such as the thigh. It can feel like an expanding pressure into the lower limb, but remains in location once established without traveling. It can wax and wane, but does so in the same location.	Travels along a narrow band into the lower limb, often distal to the knee, no more than 2 inches wide
Neurological signs	Not characteristic	Favours radicular pain, but not required.
Neuroanatomical basis	Discharge of the peripheral nerve endings of Aδ and C fibres from the lower back converge onto second order neurons in the dorsal horn that also receive input from from the lower limb, and so the frontal lobe has no way of knowing where the pain came from.	Heterotopic discharge of Aδ, Aβ, and C fibres through stimulation of a dorsal root or dorsal root ganglion of a spinal nerve, typically in the presence of inflammation, with pain being felt in the peripheral innervation of the affected nerve