Herniated disc

A herniated disc, also called a slipped or prolapsed disc, is when a soft cushion of tissue between the bones of your spine bulges outwards. It is painful if it presses on a nerve, and it usually gets better slowly with rest, gentle exercise and painkillers (NHS).

What happens in a herniated disc?

Each intervertebral disc has a gel-like centre, the nucleus pulposus, held inside a tough ring of layered collagen, the annulus fibrosus (Al Qaraghli & De Jesus, 2023). In a herniation, disc tissue bulges out beyond the disc’s normal edge and can press on nerves (NHS). In the lower back, about 95% of herniations happen at the two lowest levels, L4 to L5 and L5 to S1 (Al Qaraghli & De Jesus, 2023).

On scans, specialists sort disc changes into types: a bulging disc, a protrusion, an extrusion and a sequestration. Those are the categories used in the studies on healing below (Chiu et al., 2015).

Symptoms of a herniated disc

According to the NHS, a slipped disc can cause (NHS):

• lower back pain or neck pain
• numbness or tingling in the shoulders, back, arms, hands, legs or feet
• problems bending or straightening your back
• muscle weakness
• pain in the buttocks, hips or legs if the disc presses on the sciatic nerve

That last pattern is sciatica, and a slipped disc is its most common cause (NHS). Nerves are easily involved because the discs form part of the openings through which the spinal nerves, at their nerve roots, leave the spine (Al Qaraghli & De Jesus, 2023).

Not every herniated disc causes symptoms, and many people never know they have one (NHS).

Is a herniated disc on a scan always the cause?

No. A review of 33 imaging studies covering 3,110 people without back pain found disc protrusions in 29% of 20-year-olds, rising to 43% of 80-year-olds, and disc bulges in 30% rising to 84%. The authors concluded that many of these findings are likely part of normal ageing (Brinjikji et al., 2015). That is one reason NICE advises against routine imaging for low back pain, with or without sciatica, outside specialist settings (NICE NG59).

Can sitting cause a herniated disc?

The NHS lists sitting down or driving for long periods among the possible causes, alongside ageing, exercising too hard, lifting heavy objects the wrong way, and being inactive or overweight. Its advice on prevention is to keep active and lift safely, and it adds that smoking weakens disc tissue (NHS). For the wider picture of back pain and chairs, see lower back pain from sitting.

Does a herniated disc heal on its own?

Often. A systematic review of people treated without surgery and scanned at least twice found that disc material shrank back in 96% of sequestrations, 70% of extrusions, 41% of protrusions and 13% of bulges. It disappeared completely in 43% of sequestrations and 15% of extrusions. Extrusions and sequestrations were significantly more likely to shrink than bulges and protrusions (Chiu et al., 2015).

The NHS advice is to keep active, starting gentle exercise such as walking or swimming as soon as you can, and to take anti-inflammatory painkillers regularly if they suit you. Surgery is not usually needed, but may be discussed if symptoms don’t improve with other treatments or weakness or numbness gets worse (NHS). NICE suggests considering spinal decompression surgery for sciatica when non-surgical treatment hasn’t improved pain or function and the scan findings match the symptoms (NICE NG59). There is more on the usual course of back pain in Will back pain go away on its own?

When to see a doctor

See a GP if painkillers aren’t helping, the pain isn’t improving after a few weeks, or back pain comes with a very high temperature, unexplained weight loss, a swelling in your back, or pain that is worse at night. Call 999 or go to A&E if you have numbness around your bottom or genitals, can’t pee, lose feeling in one or both legs, can’t control when you pee or poo, or the pain followed a serious accident (NHS).