Coccyx







The coccyx (pronounced cock-six) is a beak shaped bone that forms the very bottom of the spine. The coccyx is pictured below. More than one coccyx is referred to as coccyges.

WHAT ARE SOME MORE DETAILS ABOUT THE STRUCTURE OF THE COCCYX?

The coccyx is part of the back of the pelvis, near the bottom of the spine. The pelvis is a massive bone made of hip bones on each side and the front, while the back part is also made of the sacrum, in addition to the coccyx. The coccyx is below the sacrum and is joined to it by a flat, circular layer of fibrocartrilage (a strong type of tissue). Although the coccyx and sacrum form a joint, they can barely move relative to each other, except during pregnancy, in which the coccyx moves about freely.

WHAT DOES THE COCCYX DO?

Because of where it is located, the coccyx is pressed on and moves forward when someone sits. In this way, the coccyx absorbs shock when you sit down.
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IS THE COCCYX DIFFERENT AT BIRTH COMPARED TO ADULTHOOD?

Yes. At birth, the coccyx is made up of four separate small bones, but they join together by age 60, as if they were one bone. The coccyx bones of men join together at an earlier time than women.

CAN THE COCCYX BE DISLOCATED OR BROKEN?

Yes to both. Sitting down with great force can cause the coccyx to be dislocated. To dislocate means to move out of order from a normal connection with another bone, such as the sacrum (see above for description). Forcible injuries, such as falls, can cause the coccyx bone to break. A previously broken coccyx is at risk at breaking again if a pregnant mother is delivering her baby. This is more likely to happen if the baby is very large, if the baby comes out in a strange position, or if the pelvis (see above) is narrow in shape.

WHAT CAN BE DONE TO TREAT A DAMAGED COCCYX?

Due to the location of the coccyx, when this bone breaks it is not possible to place it in a cast like you would do in the case of a broken arm or leg. However, the goal is still to keep the lower back inflexible so that it does not bend. This means relaxing, bed rest, and taking it easy. Lying down on one side is usually the most comfortable position for people with this type of injury.

Doctors generally recommend that if people with a broken coccyx need to sit that they do so on a pillow, preferable one that is ring-shaped. These types of pillows look like big doughnuts. The least amount of pressure should be placed on the coccyx while sitting. Resting and keeping the area stable usually allows the broken coccyx to heal naturally.

Ice packs, in addition to rest, usually help to provide pain relief. Pain medications may also be prescribed by your doctor if the pain has not improved after about a week. Physical therapists can help relieve pain that exists afterwards, especially if the pain is associated with weakened muscles and ligaments near the coccyx. A ligament is a tough band of tissue that attaches to joint bones. Pain relief after a broken coccyx has healed can sometimes be achieved through a chiropractor. A chiropractor is a type of doctor that uses his/her hands to manipulate and adjust structures in the body, such as the bones surrounding the spine. If pain exists in the area of the coccyx one year after it has broken, a last resort is to consider surgery to remove the coccyx.
WHERE DOES THE COCCYX COME FROM?

The coccyx is all that is left of the tailbone of animals we evolved (changed into over time) from in the past.

WHAT ELSE IS THE COCCYX KNOWN AS?

The coccyx is also known as the tailbone.

WHAT IS THE ORIGIN OF THE TERM, COCCYX?

Coccyx comes from the Greek word "kokkyx" meaning "cuckoo's beak," which is what the coccyx bone is shaped like.