Low Back Pain & Radiculopathy

Low back pain is pain between the lower ribs and the buttock creases; most of it is non-specific, and sciatica is radicular leg pain from an irritated or compressed lumbar nerve root.

It is the leading cause of years lived with disability worldwide, and most episodes improve over weeks. UK care follows current NICE guidance: exclude specific causes, stratify risk, keep people active, use exercise first and image only when the result would change management.

The lumbar spine has 5 vertebrae separated by intervertebral discs, with facet joints posteriorly. The spinal cord ends at the conus medullaris, around L1 to L2, and the cauda equina nerve roots run through the canal below this.

Radicular pain is sharp, shooting, dermatomal leg pain from an irritated root; there may be no neurological deficit. Radiculopathy is objective loss: weakness, sensory change or reflex change.

Disc herniation patterns:

• •Posterolateral (the most common): compresses the traversing root, so an L4/5 disc affects L5 and an L5/S1 disc affects S1
• •Far lateral (foraminal): compresses the exiting root at the same level
• •Central: may compress the cauda equina

Degenerative MRI changes are common in pain-free adults and increase with age. Spinal stenosis from disc bulge, facet hypertrophy and ligamentum flavum thickening causes neurogenic claudication in older adults.