Inflammation of the tailbone (coccyx or bony area located deep between the buttocks above the anus) is referred to as coccydynia. Coccydynia is associated with pain and tenderness at the tip of the tailbone between the buttocks. Sitting often worsens coccyx pain.
Giving birth is one of the most common causes of coccydynia. The coccyx becomes more flexible towards the end of pregnancy due to the release of a hormone called relaxin. This makes the soft tissues around the pelvic girdle more flexible so that the birth canal can expand, allowing you to 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.
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 or falling backwards. 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).
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, leading to damage. If this happens, your muscles will no longer be able to hold your coccyx in the correct position, causing pain and discomfort.
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.
Being Under or Overweight
Being overweight or obese can place excess pressure on your coccyx when you’re sitting down. Conversely, 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 online find out whether you are a healthy weight for your height.
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.
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), if you have redness or swelling in this area contact your GP or NHS 111 service.
The following advice may help reduce pain and allow you to get on with your everyday activities.
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: