Few phrases frighten people more than "you've got a disc bulge". It sounds structural, permanent, and like something that will need surgery.
The research says something very different — and the single most useful number in this whole article is that around two thirds of herniated discs shrink back on their own.
At a glance
- What: the soft centre of a spinal disc pushing against its outer wall, sometimes irritating a nearby nerve
- Feels like: back pain, or leg pain and pins and needles — sciatica — which is often worse than the back pain itself
- The key number: a meta-analysis of 11 studies found spontaneous resorption in 66.6% of cases
- Surgery: needed by a minority; most people improve without it
- Referral needed: no — but check the red flags below first
What a disc actually is
Between each pair of bones in your spine sits a disc: a tough fibrous ring with a softer gel-like centre. It is a shock absorber and a pivot, and it is far more robust than the word "slipped" suggests. Discs do not slip. They are firmly attached top and bottom and cannot move out of place.
What can happen is that the softer centre presses outward against the ring — a bulge — or pushes through a weakness in it — a herniation. If that material contacts or chemically irritates a nearby nerve root, you get symptoms down the leg.
The words you will hear
- Disc bulge — broad, even outward pressing. Extremely common and frequently painless.
- Disc protrusion / herniation — a more focal push through the ring.
- Disc extrusion / sequestration — material further out, or separated. Sounds worst; interestingly these are the ones most likely to be resorbed by the body.
- Degenerative disc disease — an unfortunate name for normal age-related change, not a disease.
The number worth remembering
A 2017 meta-analysis pooling 11 cohort studies examined how often lumbar disc herniations shrink without any surgery. The overall rate of spontaneous resorption was 66.66%.
Your body actively breaks down and reabsorbs herniated disc material. And the larger, more dramatic-looking herniations were more likely to resorb than the small contained ones, not less.
“I show people that number in the first session, because the scan report has usually done a lot of damage before they reach me. Someone reads ‘herniation at L5–S1’ and stops bending, stops lifting, stops walking — and then we are treating deconditioning and fear on top of a disc that was always going to settle.”
Anand VaghasiyaPhysiotherapist and Director, UpPlus Physiotherapy SeatonWhy your scan report sounds worse than you feel
This is the other half of the picture. Studies imaging people with no back pain at all find disc bulges in a large proportion — and the proportion climbs steadily with age. Disc degeneration is present in the majority of pain-free people by their forties and fifties.
In other words, a bulging disc on a scan is often an ordinary finding for your age, like grey hair. It may be the cause of your pain. It may be a bystander. The scan alone cannot tell you which, which is why findings have to be interpreted alongside your symptoms and examination rather than read on their own.
What it feels like
- Lower back pain, often one-sided
- Leg pain — down the buttock, thigh, calf, sometimes into the foot. Frequently worse than the back pain.
- Pins and needles or numbness in part of the leg or foot
- Worse with sitting, bending forward, coughing or sneezing
- Sometimes easier walking or standing than sitting
- Weakness — catching a toe, difficulty on tiptoes or heels
Red flags — get seen the same day
Go to an emergency department if you have:
- Difficulty passing urine, loss of bladder or bowel control
- Numbness around the saddle area — the parts that touch a bicycle seat — or the genitals
- Numbness or weakness in both legs
- Rapidly worsening or severe leg weakness — a foot that drags
These can indicate cauda equina syndrome, which is rare but a genuine surgical emergency where hours matter. Also see a doctor promptly for back pain with fever, unexplained weight loss, a history of cancer, or pain after significant trauma.
Physiotherapy management may include
- Screening for the red flags above, and a neurological examination — reflexes, power, sensation.
- Explaining the findings properly. Reframing a frightening scan report is not a soft extra; what a person believes about their back changes what they do with it, and that changes the outcome.
- Finding your directional preference. Many people have movements that centralise symptoms — drawing leg pain back towards the spine. Finding those early is often the fastest source of relief.
- Graded movement and loading, rebuilding tolerance for sitting, bending and lifting rather than avoiding them permanently.
- Strengthening — hips, trunk and legs. The part that holds the improvement.
- Nerve mobility work where leg symptoms dominate.
- Hands-on treatment to make movement more comfortable so the active work can progress.
- Walking, built up gradually. Unglamorous and consistently useful.
- Return-to-work and lifting advice — practical, specific to your job.
- Onward referral if weakness progresses or symptoms are not improving, so imaging or a specialist opinion can be arranged.
What about surgery?
Surgery has a clear role for a minority: significant or progressing weakness, cauda equina, or severe pain that has not responded to good conservative care over a reasonable period. For most people with disc-related leg pain, the evidence supports trying conservative management first — which is exactly what the resorption figures would predict.
That decision belongs to you, your GP and a surgeon. What physiotherapy contributes is helping you through the period where the disc is settling, and making sure you come out of it stronger rather than deconditioned.
How long does it take?
Leg pain from a disc often improves substantially over six to twelve weeks, though it varies widely and some people take considerably longer. As with any nerve involvement, the order of recovery is usually pain first, then pins and needles, with numbness the last to fade — occasionally lingering months after everything else is fine.
What you can do now
- Keep moving. Bed rest makes disc-related pain worse, not better. Short, frequent walks beat lying still.
- Change position often. Sitting usually loads a disc most — get up regularly rather than enduring.
- Do not stop bending forever. Modify while it is irritable, then rebuild. Permanent avoidance is its own problem.
- Notice what centralises it. If something pulls the pain out of your leg and back towards your spine, that is valuable.
- Try not to over-read the scan. The report describes your anatomy, not your future.
Getting seen in Adelaide's west
You do not need a referral to see a physiotherapist in Australia — but if any red flag above applies, go to an emergency department rather than booking an appointment.
If your GP has written a Chronic Condition Management Plan, we bulk bill those sessions in full. We claim every registered Australian health fund on the spot through HICAPS, and handle NDIS, DVA, ReturnToWorkSA and motor accident claims. Hydrotherapy suits some people whose back will not yet tolerate land-based exercise.
We are at 177 Trimmer Parade, Seaton SA 5023 with free off-street parking, seeing people from Findon, Fulham Gardens, West Lakes, Woodville, Grange, Henley Beach, Royal Park and Kidman Park. Our physiotherapists speak English, Hindi and Gujarati — see languages we speak.
More on our disc herniation, sciatica and lower back pain pages, or book online. You can also call 0403 907 587.
This article is general information, not individual medical advice. Back and leg pain have several possible causes and the right approach depends on your examination findings. The red flags listed above need urgent medical assessment, not physiotherapy. Please discuss your own symptoms with a qualified health professional.
