Coccydynia occurs when your coccyx, or the surrounding tissue, becomes 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 a third of cases it is not possible to identify a cause.

The various possible causes of coccydynia are outlined below.

Childbirth

Giving birth is thought to be the most common cause of coccydynia.

If you are pregnant, your coccyx will become more flexible towards the end of your third trimester (from week 27 to the birth). This is due to a release of hormones in your body which allow your coccyx, and the part of your spine above it, to bend and give way when you give birth.

But in some cases, childbirth can cause the muscles and ligaments (stretchy tissue that connects bones) around your coccyx to overstretch. This means these muscles and ligaments become permanently altered and can no longer hold your coccyx in the right position. This leads to coccydynia.

Injuring your coccyx  

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

Other ways that you can injure your coccyx include:

• falling over while skiing or ice-skating
• falling from high up, such as from a horse, and landing on your coccyx
• accidentally landing on one of the bars at the side of a trampoline

Although uncommon, injury to the coccyx has also been known to happen during sexual intercourse, particularly anal sex.

In most cases where the coccyx is injured, it will only be badly bruised. However, if your coccyx is severely injured, it may be partly dislocated (moved out of joint) or fractured (broken). If this happens, the bones that make up your coccyx may move around and cause pain, particularly when you are sitting.

Repetitive strain injury (RSI)

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

If this motion is repeated many times, or if you hold a leaning forward position for a long period of time, 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, and this will cause you 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 are sitting down. This can cause coccydynia or make an existing case of coccydynia worse.

However, 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. In addition the bones that make up the coccyx can become more tightly fused together. These can place more stress on the coccyx, leading to pain.

Cancer

A less common cause of coccydynia is cancer. This can be cancer that first starts in the bone (sarcoma, which is an extremely rare type of cancer) or cancer that starts somewhere else in the body, such as the colon, and then spreads into the bone (metastatic cancer).

Joint

Joints are the connection point between two bones that allow movement.

Ligaments

Ligaments are made of fibrous tissue. They connect bone to bone, providing support while allowing flexibility and movement.

Pain

Pain is an unpleasant physical or emotional feeling that your body produces as a warning sign that it has been damaged.

Spine

The spine supports the skeleton, and surrounds and protects the delicate spinal cord and nerves. It is made up of 33 bones called the vertebrae.

Tissue

Body tissue is made up of groups of cells that perform a specific job, such as protecting the body against infection, producing movement or storing fat.

Coccydynia is a type of lower back pain felt around the last bone at the base of the spine (known as the coccyx or tailbone).

The pain of coccydynia can range from mild to severe and is usually worse when:

• sitting down – particularly if you are leaning backwards
• moving from sitting to a standing position

Some people can only tolerate sitting in the same position for a few minutes before having to move to relieve the pain.

The pain in and around your coccyx can sometimes make it very difficult to carry out everyday activities, such as driving, bending over or sitting down.

It may seem odd, but sitting on a soft surface may be more painful than sitting on something hard. This is because sitting on a soft surface places most of your weight on your coccyx rather than on the hard bones below your pelvis.

Other symptoms

As well as pain in your coccyx, other symptoms of coccydynia may include:

• backache
• shooting pains down your legs
• pain before or when you pass stools
• pain during sex
• painful buttocks and hips
• in women: increased pain during your period

If you have coccydynia, the pain in your coccyx can also make it difficult to sleep comfortably at night. You may need to keep changing positions while lying in bed.

What causes coccydynia?

Coccydynia can occur when something damages the coccyx or surrounding area, such as:

• the muscles and ligaments supporting the coccyx stretching out of place during childbirth
• trauma to the coccyx, resulting from an accident
• pulling the coccyx out of its normal position, either through poor posture or repeated activity, such as cycling or rowing

In around a third of cases of coccydynia, no obvious cause can be found, although age-related “wear and tear” may play a part.

Read more about the causes of coccydynia.

When to seek medical advice

See your GP if you have persistent lower back pain that lasts more than a few days.

While coccydynia is not usually a serious condition it is important your GP examines you in case there is a more serious and less common cause of your symptoms, such as a fracture.

In most cases, they can diagnose coccydynia based on your symptoms and a physical examination of your lower back and spine.

In some cases your GP may refer you for further tests, such as: 

• two X-rays (one sitting and one standing) – comparing the two images will help determine whether your coccyx is moving more than normal when you sit or stand
• an MRI scan – to check for other conditions, such as a bone infection or bone cancer, which may be causing unexplained symptoms

X-rays can also be used to check if any of the bones that make up the coccyx have been fractured.

Treating coccydynia

Painkillers, such as ibuprofen, are the first step in trying to treat coccydynia and in most cases the pain will resolve within a few weeks.

If this fails, stronger treatment, such as steroid injections (corticosteroids) will be recommended.

In a minority of cases the pain can persist for more than three months, which is known as chronic coccydynia. Chronic coccydynia is unlikely to clear up by itself and will probably require a combination of treatments.

There are a number of things you can do yourself to help with the pain, including using specially designed cushions to support the coccyx.

Spinal manipulation techniques such as physiotherapy, osteopathy and chiropractic can also provide short-term relief from pain.

In a small number of cases surgery may be required to remove the coccyx (coccygectomy).

Read more about the treatment of coccydynia.

Who is affected

Coccydynia is uncommon. It is estimated around one in 100 cases of lower back pain are the result of coccydynia. Women are five times more likely to develop coccydynia than men due to the association with childbirth.

Older adults are more prone to coccydynia, but the condition can affect people of all ages, including children.

Pain

Pain is an unpleasant physical or emotional feeling that your body produces as a warning sign that it has been damaged.

Physiotherapy

Physiotherapy is a treatment that uses physical movements, massage and exercise to relieve illness or injury.

Spine

The spine supports the skeleton, and surrounds and protects the delicate spinal cord and nerves. It is made up of 33 bones called the vertebrae.

The treatment for coccydynia will vary depending on what is causing your condition and how painful it is.

Various treatment options are described below.

Medication

Anti-inflammatory painkillers (NSAIDs)

If your pain and discomfort is mild to moderate, treatment with painkillers may be enough to relieve your symptoms.

Your GP may recommend or prescribe a type of painkiller known as a non-steroidal anti-inflammatory drug (NSAID). As well as easing pain, NSAIDs will also help reduce inflammation (swelling) around your coccyx. They are most effective when taken regularly, rather than when your symptoms are at their most painful. Ibuprofen is a type of NSAID available over-the-counter without a prescription.

Some people can’t take NSAIDs because they are allergic to them, or have an increased risk of developing stomach ulcers. If this is the case, you can use the over-the-counter painkiller paracetamol.

Other painkillers

In cases of more severe or long-term (chronic) coccydynia, a stronger painkiller called tramadol may be required. Tramadol may cause side effects, such as constipation, headaches and dizziness.

Tramadol is 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.

Injections

If the coccydynia doesn’t respond to painkillers, the doctors may try injecting medication into your lower back to help relieve pain.

Different types of injections can be used, and they are described below.

Corticosteroid injections

Corticosteroids reduce inflammation (swelling) and pain. Sometimes, corticosteroids are combined with local anaesthetic to make them even more effective.

Corticosteroid injections relieve the symptoms of coccydynia, although the effects may only last for several weeks at a time.

Corticosteroid injections can’t cure your condition and too many corticosteroid injections can damage your coccyx and lower back, so you may only be able to have this type of treatment once or twice a year.

Ganglion impar nerve block

The ganglion impar are a cluster of nerves next to your coccyx. It is through these nerves that many of the pain signals travel.

A ganglion impar nerve block temporarily suppresses these nerves by injecting them with a local anaesthetic to stop them transmitting pain signals.

This can be permanent in some people. In others, the pain will return after a few weeks or months, although the level of pain is usually lower.

Unlike corticosteroid injections, it is usually safe to have repeated injections of local anaesthetic.

Sacrococcygeal joint injections

The two main joints that hold the coccyx and the rest of the spine in place are known as the sacrococcygeal joints.

In cases where it is thought inflammation or other damage to the sacrococcygeal joints are causing coccydynia, the joints may be directly injected with a combination of corticosteroids and local anaesthetic.

Spinal manipulation

There is limited evidence that spinal manipulation may be effective in providing short-term pain relief in some people with coccydynia.

Types of spinal manipulation include:

• physiotherapy – a treatment that uses physical methods, such as massage and manipulation, to promote healing and wellbeing
• osteopathy – a manipulation technique that some people claim can detect and treat problems with the muscles, nerves and joints
• chiropractic – a manipulation technique that is based on the theory that many health problems are related to misalignments of the spine

Osteopathy and chiropractic are what are known as complementary and alternative medicines (CAMS), as they differ in important ways from more conventional treatments. Unlike conventional treatments, the use and principles of CAMS are not always based on scientific evidence.

If you decide to use a form of CAM to treat coccydynia, always ensure your therapist is fully qualified and an accredited member of the appropriate organisation, such as the General Chiropractic Council or the General Osteopathic Council.

Surgery

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

Your coccyx may need to be completely removed in an operation called a coccygectomy. Alternatively, you may only have part of your coccyx removed in a procedure known as a partial or limited coccygectomy.

A coccygectomy is carried out under general anaesthetic. Your surgeon makes a small cut in the skin over your coccyx, so it can be removed. The muscles, tendons and ligaments attached to the coccyx are reattached to other parts of your pelvis to preserve their function.

The most common complication of a coccygectomy is a post-operative infection, which occurs in around a third of cases. It is thought infections are so common because the coccyx is located next to the rectum and anus, making it easy for bacteria from these areas to spread to the site of the operation.

Minor to moderate infections can be treated with antibiotics. However, more serious infections may need additional surgery to remove or repair diseased tissue.

Following surgery, around 80% to 90% of people will experience a marked improvement in their symptoms, although it can take several months.

The remaining 10% to 20% will continue to experience pain.

It is important to be aware that a coccygectomy has a long recovery time. It can take anywhere from a few months to a year to recover.

Anaesthetic

Anaesthetic is a drug used to either numb a part of the body (local), or to put a patient to sleep (general) during surgery.

Anti-inflammatory

Anti-inflammatory medicines reduce swelling and inflammation.

Corticosteroid

Corticosteroid is a naturally occurring hormone produced by the adrenal gland, or a synthetic hormone having similar properties. It is used to reduce inflammation, so reducing swelling and pain.

Incision

An incision is a cut made in the body with a surgical instrument during an operation.

Inflammation

Inflammation is the body’s response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.

Pain

Pain is an unpleasant physical or emotional feeling that your body produces as a warning sign that it has been damaged.

Spine

The spine supports the skeleton, and surrounds and protects the delicate spinal cord and nerves. It is made up of 33 bones called the vertebrae.