You get coccydynia when your coccyx (tailbone), or the surrounding tissue, is damaged. This causes pain and discomfort at the base of your spine, particularly when sitting down.

The coccyx can be damaged in various ways, although in many cases it's not possible to identify a cause.

The main causes of coccydynia include:

Childbirth

Giving birth is one of the most common causes of coccydynia.

The coccyx becomes more flexible towards the end of pregnancy. This allows your coccyx, and the part of your spine above it, to bend and give way when you give birth.

Sometimes childbirth can cause the muscles and ligaments (stretchy tissue that connects bones) around your coccyx to overstretch. This can result in coccydynia.

Injuring your coccyx

You can injure your coccyx if you suffer a hard impact to the base of your spine. For example, from an accidental kick during contact sports.

Falling backwards is another common cause of injury to the coccyx.

In most cases where the coccyx is injured, it will only be badly bruised. But in more severe injuries, it may be dislocated (out of place) or fractured (broken).

Repetitive strain injury (RSI)

You may get coccydynia if you regularly take part in sports such as cycling or rowing. This is due to continually leaning forward and stretching the base of your spine.

If this motion is repeated many times, the muscles and ligaments around your coccyx can become strained and stretched.

Straining your muscles and ligaments can permanently damage them. If this happens, your muscles will no longer be able to hold your coccyx in the correct position, causing pain and discomfort.

Read more about repetitive strain injury (RSI).

Poor posture

Sitting in an awkward position for a long period of time, such as at work or while driving, can put too much pressure on your coccyx. This causes pain and discomfort that will get worse the longer you stay in this position.

Read more information about how to sit correctly.

Being overweight or underweight

Being overweight or obese can place excess pressure on your coccyx when you're sitting down. This can cause coccydynia or make existing coccydynia worse.

You may also develop coccydynia if you are very slim. If this is the case, you may not have enough buttock fat to prevent your coccyx from rubbing against the tissues surrounding it.

You can use the body mass index (BMI) calculator to find out whether you are a healthy weight for your height.

Ageing

As we grow older the small discs of cartilage (a tough, flexible tissue) that help hold the coccyx in place can wear down. The bones that make up the coccyx can also become more tightly fused together. This can place more stress on the coccyx, leading to pain.

Infection

Rarely, an infection can occur in the base of the spine or soft tissue and cause coccydynia, such as a pilonidal abscess (a painful collection of pus that usually develops in the cleft of the buttocks).

Cancer

A rare cause of coccydynia is cancer. This can be bone cancer or cancer that starts somewhere else in the body and then spreads into the bone (metastatic cancer).

There are a number of treatments that can help reduce the pain of coccydynia. Simple measures you can try at home are usually recommended first.

Coccydynia often improves over a few weeks or months. If it continues despite simple treatments, your GP may refer you to a specialist to discuss other options.

Self care measures

The following advice may help reduce pain and allow you to get on with your everyday activities.

• use a specially designed coccyx cushion – these can be bought online and from some shops; they help reduce the pressure on your tailbone while you're sitting down
• avoid prolonged sitting whenever possible – try to stand up and walk around regularly; leaning forward while seated may also help
• wear loose-fitting clothes – avoid clothing such as tight jeans or trousers that may put pressure on your tailbone
• apply warm and cold packs to your tailbone – warm packs include hot water bottles and microwaveable heating pads; cold packs are available as freezable gel-filled pads from pharmacies, or you can use a bag of frozen vegetables wrapped in a towel
• try laxatives (medicines to treat constipation) if the pain is worse when you are having a poo – many laxatives are available to buy from pharmacies and supermarkets without a prescription
• take over-the-counter painkillers

Painkillers

Anti-inflammatory painkillers (NSAIDs)

If your pain and discomfort is not too severe, it may be relieved with over-the-counter painkillers.

A type of painkiller known as a non-steroidal anti-inflammatory drug (NSAID) is often recommended. Ibuprofen is a type of NSAID available without a prescription.

NSAIDs can help ease pain and reduce inflammation (swelling) around your coccyx.

However, some people cannot take NSAIDs because they're allergic to them or have an increased risk of developing stomach ulcers. If this is the case, try taking paracetamol instead. Ibuprofen gel that you rub into your skin may also be an option.

Ask a pharmacist or GP for advice if you're unsure what to take.

Other painkillers

If the pain is more severe, a stronger painkiller such as tramadol may be required. Tramadol can cause side effects, such as constipation, headaches and dizziness.

It's usually prescribed for a short time as it can be addictive. If it's prescribed for longer, the dose will have to be reduced gradually before being stopped to avoid withdrawal symptoms.

Physiotherapy

If your pain has not started to improve after a few weeks, your GP may be able to refer you to a physiotherapist.

A physiotherapist can:

• give you advice about posture and movement to help reduce your pain
• teach you some simple exercises to help relax the muscles around your tailbone
• try techniques such as massage and stretches

Read more about physiotherapy.

Injections

If your coccydynia does not respond to painkillers, your doctor may recommend injecting medicine into your lower back.

Several different types of injections can be tried.

Steroid injections

Injections of corticosteroids into the area around the tailbone can reduce inflammation and pain. Sometimes, they're combined with local anaesthetic to make them even more effective.

The injections can help relieve the symptoms of coccydynia, although the effects may only last for a few weeks.

They cannot cure your condition and too many injections can damage your tailbone and lower back, so you may only be able to have this type of treatment once or twice a year.

Nerve blocks

Injecting local anaesthetic into the nerves that supply the coccyx can help reduce the pain signals coming from them.

As with steroid injections, the effect may only last a few weeks or months.

But unlike steroid injections, it's usually safe to have repeated injections of local anaesthetic.

Surgery

Surgery for coccydynia is usually only recommended when all other treatments have failed.

It may involve removing some of your tailbone (partial coccygectomy) or occasionally all of it (total coccygectomy).

A coccygectomy is carried out under general anaesthetic (where you're asleep).

After surgery, most people find their symptoms improve considerably, although it can take several months. Some people will continue to experience pain.

It takes a long time to recover from coccygectomy, anywhere from a few months to a year.