The coccygeus muscle or ischiococcygeus is a muscle of the

pelvic floor The pelvic floor or pelvic diaphragm is composed of muscle fibers of the levator ani, the coccygeus muscle, and associated connective tissue which span the area underneath the pelvis. The pelvic diaphragm is a muscular partition formed by the lev ...

, located posterior to

levator ani The levator ani is a broad, thin muscle group, situated on either side of the pelvis. It is formed from three muscle components: the pubococcygeus, the iliococcygeus, and the puborectalis. It is attached to the inner surface of each side of the ...

and anterior to the

sacrospinous ligament The sacrospinous ligament (small or anterior sacrosciatic ligament) is a thin, triangular ligament in the human pelvis. The base of the ligament is attached to the outer edge of the sacrum and coccyx, and the tip of the ligament attaches to the s ...

Structure

The coccygeus muscle is posterior to

and anterior to the

in the

. It is a triangular plane of muscular and tendinous fibers. It arises by its apex from the spine of the ischium and

. It is inserted by its base into the margin of the

coccyx The coccyx ( : coccyges or coccyxes), commonly referred to as the tailbone, is the final segment of the vertebral column in all apes, and analogous structures in certain other mammals such as horses. In tailless primates (e.g. humans and othe ...

and into the side of the lowest piece of the sacrum. In combination with the

, it forms the

pelvic diaphragm The pelvic floor or pelvic diaphragm is composed of muscle fibers of the levator ani, the coccygeus muscle, and associated connective tissue which span the area underneath the pelvis. The pelvic diaphragm is a muscular partition formed by the le ...

. The

pudendal nerve The pudendal nerve is the main nerve of the perineum. It carries sensation from the external genitalia of both sexes and the skin around the anus and perineum, as well as the motor supply to various pelvic muscles, including the male or fem ...

runs between the coccygeus muscle and the

piriformis muscle The piriformis muscle () is a flat, pyramidally-shaped muscle in the gluteal region of the lower limbs. It is one of the six muscles in the lateral rotator group. The piriformis muscle has its origin upon the front surface of the sacrum, and ins ...

, superficial to the coccygeus muscle.

Nerve supply

The coccygeus muscle is innervated by the

, which runs between it and the

Function

The coccygeus muscle assists the

and

in closing in the back part of the outlet of the pelvis. This helps to support the

vagina In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen ...

women A woman is an adult female human. Prior to adulthood, a female human is referred to as a girl (a female child or adolescent). The plural ''women'' is sometimes used in certain phrases such as "women's rights" to denote female humans regardl ...

, and the other pelvic organs.

References

External links

* - "The Female Pelvis: Muscles of the Pelvic Diaphragm" * * (, )
Coccyx pain, tailbone pain, coccydynia
(Peer-reviewed medical chapter, available free online at eMedicine) {{Authority control Muscles of the torso

Structure

Nerve supply

Function

See also

References

External links