Coccydynia
Coccydynia is also known as coccygodynia or tailbone pain. This pain condition normally resolves with supportive care but can occasionally become persistent. The effects on quality of life can be dramatic.
Anatomy
The coccyx has between three to five vertebrae. A Turkish MRI based anatomy study found significant variation in asymptomatic people.[1] They found having four segments was the most common, followed by five, then three. They also found a significant rate of intercoccygeal joint fusions, which was most prominent in the most caudal joint. Fusion of the whole structure into one segment was uncommon. The authors found the intercoccygeal angle to be 135ยฐ ยฑ 1.15ยฐ, with a higher angle in those with a single segment.
Epidemiology and Risk Factors
The overall prevalence is unknown.[2] The female to male ratio is 5:1.[2] The coccyx is more posteriorly located in women, which is thought to be a risk factor for trauma.[2] It is also more common in obese individuals.[2]