Herniated disc
A disc in the spine bulges out and presses on a nerve, causing pain, numbness or weakness along the path that nerve supplies. Most people improve without surgery.
What it is
Between each pair of vertebrae sits an The cushion between two vertebrae — a tough outer ring around a softer, gel-like centre. It absorbs load and lets the spine bend., which absorbs load and lets the spine bend. It has a tough outer ring and a softer, gel-like centre.
When the outer ring weakens or tears, the centre can push outwards. If it pushes out where a nerve is, it presses on or irritates that nerve.
The commonest site is the lower back, causing pain down the leg. Next is the neck, causing pain down the arm.
Symptoms
These depend on which nerve is compressed.
In the lower back
- Pain from the back or buttock down the leg, usually past the knee, usually one side
- Numbness or tingling along the same path
- Worse coughing, sneezing, straining, or sitting for long periods
- Sometimes leg weakness — you cannot lift the front of your foot, or rise onto your toes
In the neck
- Neck pain spreading to the shoulder blade, upper arm, and down to the fingers
- Numbness or tingling in particular fingers
- Arm weakness — your grip is not what it was
Signs the spinal cord itself may be compressed: hands that have become clumsy so buttons are difficult, unsteady walking, or weakness in both legs. These need to be seen quickly.
Causes and risk factors
- Age-related change making the outer ring more brittle — commonest between 30 and 50
- Lifting badly, especially bending and twisting under load
- Long periods of sitting with little movement
- Carrying extra weight
- Smoking, which reduces the blood supply to the disc
- Family history, which matters more than most people realise
When to see a doctor
Otherwise, see a doctor when the radiating pain has not improved after four to six weeks, when it stops you working or sleeping, or when there is any weakness at all.
How it is diagnosed
History and examination tell your doctor the most. They test muscle strength, sensation along the skin, reflexes, and the positions that put the nerve on stretch. Together these point to the level involved.
MRI shows the disc and nerve most clearly, but is not needed early on without warning signs, because it rarely changes treatment.
X-ray does not show the disc, but shows stability and rules out other causes.
Nerve conduction studies are used in some people to distinguish this from a problem in the nerves further out.
Treatment options
Non-surgical treatment
Most people get better without surgery, and the body often reabsorbs the bulging part over time.
- Keep moving and return to activity gradually, avoiding only what clearly makes the arm or leg symptoms worse
- Pain relief as advised. Always ask a doctor or pharmacist first, particularly with stomach, kidney or bleeding problems, or blood thinners
- Physiotherapy to reduce pain, adjust posture, and gradually build trunk and hip strength
- A spinal injection, your doctor’s decision, usually when severe pain is blocking rehabilitation
Surgery
Your doctor considers surgery when there is clear and worsening weakness, when severe pain has not settled after roughly six to twelve weeks of other treatment, or when the lowest bundle of nerves is compressed and needs urgent decompression.
The usual operation removes the part of the disc pressing on the nerve. It generally helps the arm or leg symptoms more than the neck or back pain itself, which is worth clarifying before deciding.
Recovery and rehabilitation
The rule for choosing exercises is to watch which way the arm or leg symptoms move. Symptoms retreating towards the trunk is the right direction; symptoms travelling further out means stop.
Prone on elbows
start with 5 · hold 10 seconds
Lie face down and prop yourself up on your elbows, placed under your shoulders, keeping the hips on the floor. Hold, then lower.
Watch for — this is for a disc in the lower back. Stop if the leg symptoms travel further down.
Chin tuck
2 rounds · 10 times · hold 5 seconds
Sit or stand tall, looking straight ahead. Gently draw your chin back towards your neck, making a double chin. Hold, then release.
Watch for — this is for a disc in the neck. Do not tip the head up or down.
Gentle abdominal bracing
2 rounds · 10 times · hold 10 seconds
Lie on your back with knees bent. Gently draw the stomach in, as if tightening a belt, while continuing to breathe normally. Hold, then release.
Watch for — do not tense so hard that you hold your breath.
Walking
20–30 minutes a day
Walk as far as you can without symptoms worsening, split into shorter spells, then build up.
Prevention and self-care
- Lift by hinging at the hips and bending the knees, not by rounding the back. Keep the load close, and never twist while lifting
- Get up and change position every 30–60 minutes
- Exercise regularly, especially walking and trunk and hip strengthening
- Keep your weight in a healthy range
- Do not smoke, because it reduces the blood supply to the disc
- Set up your desk so your feet are flat, your back is supported, and the screen is at eye level
Questions to ask your doctor
- Which nerve level is my disc pressing on, and does that match my symptoms?
- Is there any weakness I should be watching for?
- Do I need an MRI now, and would it change the treatment?
- How long should I give non-surgical treatment before we consider anything else?
- If I have surgery, how much would it help the radiating pain compared with the back or neck pain?
Frequently asked questions
Can a bulging disc go back in?
The body gradually reabsorbs the bulging part in a good many people, and MRI scans repeated months later often show it has shrunk. That is one reason doctors usually suggest giving it time before deciding on surgery.
If the MRI shows a disc on the nerve, do I need an operation?
No. Bulging discs are found on scans in very many people with no symptoms at all. The decision is based on your symptoms, the examination, and the effect on your life — not on the picture alone.
Should I avoid lifting for good?
No. Once things have settled, gradually returning to lifting with good technique is a good thing. A strong back is a back that gets used. Avoiding everything permanently tends to lead to weakness and fear of movement.
Do traction or spinal manipulation help?
The evidence that they beat exercise and ordinary care is not clear. Some people feel better in the short term. If you have it, have it after a doctor has excluded warning signs, and from someone properly trained.
References
Related educational reading
These pages explain tests, treatments and rehabilitation that often come up with this condition. They are general reading, not a treatment sequence arranged for you — that has to come from a doctor who has examined you.
Related conditions
Written by Assoc. Prof. Sorawut Thamyongkit, M.D.