“Sciatica” is not a diagnosis. It is a description of a location.
It means pain travelling down the back or side of the leg along the distribution of the sciatic nerve or its contributing nerve roots. It is also called lumbar radiculopathy, nerve root pain, radicular leg pain, referred leg pain, or lumbar nerve compression.
What it does not tell you is the cause. And the assumption that the cause is always a disc protrusion sends a great many people down a path they don’t need.
The list of things that produce leg pain
Disc herniation or protrusion. Genuinely common, particularly under 55. A disc extrusion compresses or chemically irritates a nerve root. This is the classic cause, and it deserves its reputation — but it is not the only one.
Lumbar spinal stenosis. Narrowing of the central canal, typically degenerative and more common over 60. The signature is neurogenic claudication — leg pain that comes on with walking, eases with sitting or leaning forward, and lets you push a shopping trolley much further than you can walk unaided.
Foraminal stenosis. Narrowing where the nerve root exits. Often worse with extension and rotation towards the painful side.
Degenerative spondylolisthesis. One vertebra slipping forward on another, narrowing the space available for the nerve.
Deep gluteal syndrome / piriformis syndrome. Entrapment or irritation of the sciatic nerve within the buttock, by piriformis or other structures.
Gluteal myofascial trigger points. Gluteus minimus in particular refers pain down the lateral or posterior leg convincingly enough to imitate true radiculopathy — without any neurological signs.
Proximal hamstring tendinopathy. Pain at the sitting bone, worse with sitting and with hip flexion, frequently mistaken for sciatica.
Sacroiliac joint referral. Refers into the buttock and posterior thigh.
Hip osteoarthritis. Usually groin pain, but can refer posteriorly and confuse the picture.
Gluteal tendinopathy. Lateral hip pain referring down the outside of the thigh.
That is nine plausible causes of “sciatica,” of which one is a disc. Yet the imaging report shows a disc bulge — because nearly everyone over 50 has one — and the case is considered closed.
The imaging problem
Brinjikji and colleagues published a systematic review in 2015 examining imaging findings in asymptomatic people — individuals with no back pain at all.
Disc degeneration was present in a substantial majority of pain-free 50-year-olds, rising with each decade. Disc bulges, annular fissures and facet degeneration were similarly common in people with no symptoms whatsoever.
Which means finding a disc bulge on the MRI of someone with leg pain does not establish that the bulge is causing the leg pain. It establishes that they have a spine of a certain age.
Why most sciatica resolves
Two reasons, and both are encouraging.
Discs resorb. This is the finding that surprises people most. Systematic reviews of spontaneous regression of lumbar disc herniation have found that a substantial majority of herniations reduce in size over time — and the larger extrusions and sequestrations regress most reliably, likely because more of the nucleus is exposed to the immune system and gets cleared.
The body treats an extruded disc fragment as foreign material and removes it. Time is doing real work.
Nerves settle. Much of the pain in acute radiculopathy is chemical irritation and inflammation rather than mechanical compression. That inflammatory process settles.
The natural history data is consistent: the large majority of acute sciatica improves substantially over weeks to a few months.
What the surgery trials show
The SPORT trials and other randomised comparisons of surgical discectomy against non-operative care for lumbar disc herniation showed a consistent pattern.
Surgery produced faster relief in the early months. But by one to two years, the outcomes between surgical and non-surgical groups converged considerably.
So the honest framing is: surgery buys speed, not necessarily a better endpoint, for most people with uncomplicated disc-related sciatica.
When surgery is the right answer
There are genuine indications, and they matter:
- Cauda equina syndrome — saddle numbness, bladder or bowel dysfunction, bilateral leg symptoms. This is a medical emergency. Go to an emergency department immediately.
- Progressive motor weakness — a foot that is getting weaker, not just painful
- Severe pain unresponsive to good non-operative care over an appropriate period
- Significant stenosis with severely limited walking distance that hasn’t responded to conservative management
Outside these, non-operative management is the appropriate first line, and it is what guidelines recommend.
What good non-operative care looks like
Not rest, and not simply waiting.
Accurate diagnosis of the actual pain source. Identification of directional preference — many people have positions and movements that reliably reduce leg symptoms, and finding them is a treatment. Nerve mobility work. Load management. Then progressive strengthening of the leg that has genuinely lost capacity — because nerve irritation causes real inhibition, and a calf or glute that has been shut down for three months needs rebuilding deliberately.
At Longevity Physio Studio in Eagle Heights, we test the calf, the glutes and the quadriceps side to side. The asymmetry is usually striking and it is almost always the thing that gets missed.
Book a sciatica assessment
If you have leg pain and you have been told it is a disc, it is worth confirming what is actually generating your symptoms before making decisions about surgery.
Longevity Physio Studio, Eagle Heights, Mt Tamborine — serving Tamborine Mountain, North Tamborine, Canungra and the Gold Coast hinterland. Book an assessment.
