Coccydynia

What are the symptoms and signs?

Patients often describe pain right at the tailbone (i.e. between the buttocks), especially when sitting on hard surfaces and when getting up from a seated position. Patients may also experience pain during defecation, intercourse or when riding bicycles or motorcycles with hard saddles. Predominantly seated sports such as cycling, and rowing can lead to this condition.

How common is it?

It typically affects those in their middle years and is more common in those who are overweight or obese. It probably accounts for less than 1% of all back pain, but interestingly it is more prevalent in women.  This may be related to the positioning of the female coccyx lying more posteriorly in the female pelvis and therefore being more prone to external trauma. It is also more common in women because of injuries related to giving birth.

What are the causes?

By far the most common cause is trauma e.g. due to childbirth or a fall, or a rough landing on a water slide.

Much rarer but more serious causes can include:

• coccygeal infection
• fracture
• arthritis
• tumours

However, in about a third of patients, coccydynia is idiopathic (i.e. cause unknown). Investigative tests & imaging used to confirm the diagnosis may include blood tests; X-rays and MRI scans.