Coccyx vertebrae

Synonym: short: tailbone; Latin: Os coccygis


The tailbone is a slightly forward arched section of the spine that results from the fusion of 2-4 vertebral bodies. This is the lowest (most caudal) Section of the spine that goes beyond the cartilaginous Sacrococcygeal joint with the sacrum (Sacrum) connected is.


The Coccyx vertebrae no longer shows a classic vortex structure. Only the first vertebra is by its short one Transverse processes still recognizable as a vortex. The remaining vertebrae are roughly square, with the last one appearing cone-shaped. The individual vertebrae are not through as in the rest of the spine Band washers connected but are fused together in bones. This is called Synostosis (Ossification). In some cases, however, the individual vertebrae are also over Cartilage plates connected with each other (Synchondroses). This shows that the tailbone vertebrae are very pronounced variable can be.

None of them emerge from the coccyx vertebrae annoy more from except for the Coccyx nerve (Coccyge nerve), which emerges from the spine at the connection between the sacrum and the coccyx vertebrae. Since the tailbone is the lowest part of the spine, they end here Tapes Longitudinal anterior and posterior ligaments (the long anterior ligament and the long posterior ligament), which span the entire spine. There is also a ligamentous connection between the sacrum and the coccyx vertebra, the so-called Sacrococcygeum ligament.

Many sat next to these ribbons Muscles of the pelvic floor on the tailbone, for example the Pubococcygeus muscle or the Iliococcygeus muscle. The pelvic floor generally serves as a holding device for the Genital organs (for example uterus), the Rectum (rectum) and the urethra (urethra). This can lead to excessive strain on this holding apparatus Tailbone pain come. This is due to the fact that the Musclesthat, for example, hold the rectum in place, are overloaded and irritated by excessive pressing. This allows it to Inflammation in the muscle come that will then focus on the sensitive Periosteum (Periosteum) of the coccyx. Even after one birth this is often the case. The tailbone is therefore exposed to constant stress. This increases if you go on for too long and too often hard ground sits (for example at the desk in the office). Due to the slightly forward-facing shape and the connection to the muscles of the pelvic floor, the tailbone is only relieved when you stands upright.


Historically, the tailbone is believed to be one functionless holdover (Rudiment) from old times. It is believed that people used to have a kind of tail, which then regressed. What remained were the few vertebral bodies of the coccyx.

Possibility of movement

The Movement possibilities in the coccyx vertebra are only forward or backward, rotations are usually not possible. Especially during childbirth but also with difficult bowel movements (Constipation) this is important after tilting backwards, because in this case the tailbone can shift backwards due to the muscle pull and thus the Basin exit level (Conjugata recta) enlarged. Only then is it possible for the child to fit through the pelvic exit level at birth.


The coccyx is primarily used as a base for the muscles of the pelvic floor. Since that pool is open at the bottom and has no bony closure, these muscles have a special meaning because they not only organs hold in place but also with for the Continence are responsible. The coccyx vertebra is therefore of crucial importance as a place of attachment for muscles. However, due to the variable number of vertebrae and the minimal support surface of the vertebral bodies, the tailbone cannot help with standing upright. Still, the tailbone is important. At osteoporosis in the tailbone it can be easier here too Fractions come, which are not only associated with severe pain but also result in a restriction, especially when sitting.


Especially Inflammation on the coccyx vertebrae are more common due to the connection to the many muscles.

Less common, however, is one contortion (dislocation) of the coccyx. However, if such a painful dislocation occurs, the doctor must go down the coccyx via the rectum (caudal) to move it to its right place. Immediately afterwards the symptoms should improve.

One is also rare Tailbone fracturewho is in tremendous pain and a Hematoma in the anal area connected is. Such a fracture can occur when skiing, for example, if you “sit down properly on your bum”. Most of the time, the tailbone has to pre-damaged be through osteoporosis or inflammation causing a rupture. Since it is not possible to cast the coccyx vertebrae, it must be removed in extreme cases (Resection of the coccyx). However, therapy with pain relievers is usually sufficient (Analgesics), Cooling and longer protection of the coccyx. The tailbone should heal again after a while, especially in younger patients.