What is actually happening

True sciatica is a nerve root problem, not a muscle problem, and the two feel different once you know what to check. Nerve pain travels in a line — down the back or side of the leg, sometimes past the knee, sometimes into the foot, often with numbness or burning layered on the ache. It is generated by pressure and chemical irritation at a specific root, most often L4, L5 or S1, where a disc fragment or narrowed foramen contacts the nerve as it exits the spine.

Two biological drivers are doing the work. The first is mechanical: a herniated disc or narrowed foramen is physically deforming the root. The second is chemical: the leaked disc material is inflammatory in its own right and sensitizes the nerve independent of how hard it is being pressed — why pain can be severe even when compression looks modest on a scan. A third driver is usually occupational: long stretches of sitting or repetitive lifting and twisting load the same discs daily, and warehouse, logistics and airport-ground workers along the Woodson corridor carry more of this than a desk-only population. The disc is where it hurts. The forklift and the pallet are often why it keeps happening.

What impersonates it

Several structures can send pain down a leg without any nerve root involved, and mistaking one for another is the most common reason a plan fails.

Foraminal stenosis — narrowing of the tunnel the nerve exits through, from bone spurring or a bulging disc — produces true radicular pain by the same mechanism as a herniation, but it does not resorb the way a fragment of disc material can, and it tends to worsen gradually rather than ease on its own. That distinction changes how patient the plan can afford to be.

How we find out which one it is

The exam comes first: reflexes, strength testing at the ankle and big toe, straight-leg raise, and palpation of the hip rotators and the sacroiliac joint. An MRI, when warranted, is read against that exam, not on its own — disc bulges show up on the scans of many pain-free adults your age, so the job is confirming the level the scan flags is the level your body is complaining about. When more than one structure is plausible, a diagnostic injection becomes the tiebreaker: an epidural steroid injection targeted at a single level tells us something a scan cannot, because relief there, even briefly, implicates it.

The injection as a window, not a repair

An epidural does not shrink a disc fragment or widen a foramen. It quiets the chemical inflammation around the root long enough for you to sleep, move and let the underlying problem run its course — which, for a genuine herniation, is often a course toward resorption. Pooled cohort data published in 2024 in Clinical Spine Surgery tracked patients across dozens of studies and found that about two-thirds of herniated fragments get visibly smaller within months even without an operation, with the biggest and angriest-looking extrusions tending to shrink the fastest. That is the case for treating the interval, not the anatomy.

Two-thirds is the working number: most lumbar disc herniations get smaller on their own within months — a population pattern, not a guarantee for any single disc.

The terrain underneath the disc

Two people can carry the same MRI and heal at very different rates, and the difference is often metabolic before it is mechanical. Insulin resistance and systemic inflammation raise the baseline the disc’s own inflammatory response is already elevated from, and impair the small-vessel circulation the nerve root and the healing disc both depend on. That is why bloodwork is part of an initial consultation, and why Acceptance and Commitment Therapy — delivered by this practice’s own behavioral clinician, never handed off to an outside referral — carries equal weight in the plan alongside the injection. Metabolic health and pain and sleep, movement and behavior cover the mechanism in full.

When surgery enters the conversation

For most sciatica, surgery is not part of the plan — conservative care and interventional treatment resolve the majority of cases, and a fragment given time to resorb often makes the operation unnecessary in retrospect. What changes the calculation is weakness that is new or getting worse, not pain severity alone. Pain, however intense, is not by itself an indication to operate; a foot drop or a deficit progressing over days is different, because a nerve that has been squeezed for too long does not reliably bounce back once it is finally freed. When conservative and interventional options are exhausted, this practice performs microdiscectomy, and the full decision is covered on herniated disc.

Red flags, in plain terms

Common questions

Related reading

• Herniated disc
• Spinal stenosis
• Sacroiliac joint pain
• Epidural steroid injection
• After a car accident