Anatomy: A Tale of a Bone called Coccyx

Breaking News… the coccyx is no longer a bone that only Women’s Health Specialists are concerned about.  As physical therapists, we spend a significant amount of time treating the spine and dysfunctions of the pelvis, pelvic floor and lower extremities.  What these areas all have in common is this one little bone that we don’t think too much about… the coccyx.

Normalization of a dysfunctional coccyx enhances objective signs in other lumbopelvic girdle structures.  Conversely, when related structures (sacrum, innominate, lumbars spine and hips) are treated, coccygeal dysfunctions rarely improve. – Gregg Johnson (Wise 2015)

Inner Body’s Graphic

The Coccyx

  • Many consider it to be the key structure for the lumbopelvic girdle (Wise 2015)
  • has important muscle attachments that influence the body beyond the pelvic floor
    • Gluteus Maximus
    • Levator Ani
    • Coccygeus
  • Has important ligamentous attachments:
    • The anococcygel ligament helps with the functioning of the anus by holding the external anal sphincter in place. (Taylor 2017)
  • is the anchor for the inferior part of the spinal cord & meninges within the spinal canal
    • Serves as the distal attachment of the filum terminal (extension of the meninges) (Moore 2014).
  • Is involved in functional activities:
    • when we are sitting, the body weight rests on the coccyx posteriorly (Taylor 2017)
    • in women, the coccyx extends to create more space for the child in the birthing process (Taylor 2017)
  • Anatomical differences in males & females (Taylor 2017)
    • males:  aligned more anteriorly
    • women: aligned more inferiorly

The Dirty Details from Moore’s Clinically Oriented Anatomy (2014).

The Pelvic Girdle: This is the ring of bones that essentially connects the spine to the femurs, bears the weight of the upper body in sitting, and provides many attachments for the muscles used for locomotion and posture.  The girdle also houses the pelvic viscera and inferior abdominal viscera. And in women, this area supports the growing fetus.

  • specifically, the coccyx makes up the pelvic outlet which is the inferior pelvic aperture.  This ring consists of the pubic arch, ischial tuberosities, inferior margins of the sacrotuberous ligament and the tip of the coccyx.
  • It also makes up the lesser pelvis which includes the pelvic cavity and the deep pars of the the pelvic floor.
    • Pelvic Floor (pelvic diaphragm): separates the pelvic cavity form the perineum

Ligamentous Attachments

  • Sacrotuberous ligament: a massive ligament that connects the posterior margin of the ilium along the scarum & coccyx to the ischiums, which helps to form to the sciatic foramen.
  • Sacrospinous ligament: this ligament further divides the sciatic foramen into the greater and lesser sciatic foramina.
    • the piriformis muscle passes through the greater sciatic foramen
    • The Inferior gluteal a. (supplies muscles and skins of the buttocks and posterior surface of the thigh) and superior gluteal a.(gluteal mm) runs through the greater sciatic foramen
    • pudendal nerve leaves the pelvis through the greater sciatic forament
    • Superior glutetal nerve: supplies motor to the mm in the gluteal region
    • Inferior gluteal nerve: glut max

These two ligaments together help to counterbalance the weight of the body when the vertebral body sustains a sudden increase in force or weight (while jumping, running, lifting weights etc.).  The superior end of the sacrum is pushed inferiorly and anteriorly, while the ligament prevents the superior and posterior rotation of the sacrum anchoring the sacrum to the ischium (Moore 2014).

  • Sacrococcygeal ligament: reinforces the sacrococcygeal joint

Muscles that attach to the coccyx:

  • Coccygeus muscles (Ischiococcygeus):
    • forms a small part to the pelvic diaphragm that supports pelvic viscera
    • flexes the coccyx
    • origin: inferior sacrum and coccyx
    • insertion: sacrospinous ligament
  • Levator ani (puborectalis, pubococcygeus and iliococcygeus)
    • forms most of the pelvic diaphragm that supports the pelvic viscera
    • resists intra-abdominal pressure
  • Pubococcygeus
    • origin: posterior aspect of the pubis and anterior tendinous arch
    • insertion: coccyx and anococcygeal body (ligament between the anus and coccyx (aka Levator plate))
  • iliococcygeus: 
    • origin: arch and ischial spine
    • insertion: blends with anococcygeal body posterior


  • Median Sacral a: blood supply for the inferior lumbar vertebrae, sacrum and coccyx

Adjacent Nerves:

  • Coccygeal plexus: formed by the rami of S4 and S5 plus the coccygeal nerves.
    • supplies: coccygeus, levator ani, sacrococcygeal joint
  • Anococcygeal nerves: pierces coccygeus and anococcygeal ligament to supply the small area of skin between the coccyx and the anus.
  • Ganglion impar (sympathetic chain) lies on the anterior aspect of the coccyx
  • Filum Terminale: the caudal part of the spinal cord that serves as an anchor of the inferior end of the spinal cord and the spinal meninges.

Positional Faults of a dysfunctional Coccyx

– From Gregg Johnson’s Functional Mobilization Approach (Wise 2014)
  • Sacrococcygeal Junction
    • Compression
    • Rotation
    • Posterior Shear: often seen after childbirth
    • Anterior Shear: result of a direct fall.
    • Lateral Translation: can be right or left
  • Dysfunctions of the Coccyx body
    • Deviation
    • Extension
    • Flexion

There are treatment strategies outlined in Wise’s book.  For more information, I recommend looking into courses by the Institute of Physical Art, specially Functional Mobilization I. (See their Schedule here.)


  1. Wise, Christopher H. Orthopaedic Manual Physical Therapy: from Art to Evidence. Philadelphia, PA, F.A. Davis Company, 2015.
  2. Taylor, Tim. “Coccyx.” InnerBody, Accessed 2 Sept. 2017.
  3. Moore, Keith L., et al. Clinically Oriented Anatomy. Philadelphia, Wolters Kluwer, 2014.


Please follow and like us:


  1. Ubobet is an internationally trusted gambling dealer back 2001
    until now. By holding qualified admission for online gambling sites that
    find the money for various types of betting games. Games genial include Sportsbook, flesh and blood Casino and Cockfight.
    Ubobet has reached the entire world gambling promote including the Indonesian market.

    At present, every day there are more than 100 thousand players
    who entrust their bets in the city of Ubobet.

    Ubobet List Site

    To register an account, players cannot realize it directly
    on the Ubobet site. In additional words, prospective players must register through the attributed agent site for Ubobet
    listings such as Pandora188. By using Pandora188 ID the artist can bet on this city.
    How to register is quite easy, just by filling out the registration form correctly.
    After that create a buildup of at least 25 thousand, next the
    artist can bet on Ubobet. all artist who joins as
    a fanatic at Pandora188 is entitled to a freebet extra and then a daily lump further without exception.

    Ubobet Login

    After registering, players can log in upon Ubobet in two
    ways. The first is through qualified cronies who have collaborations such as Pandora188.
    Because the two sites have already formed a partnership, which means that
    betting on the Pandora188 site is the thesame as betting on Ubobet directly.
    Or by the second habit you can directly log in to the Ubobet site if you already have an account.

    How to log in Ubobet is quite easy, just enter your ID & password correctly.


  2. One of the most popular online gambling games in Indonesia is online slot games.
    Apart from creature simple to acquit yourself and not
    requiring a complicated strategy, slot gambling plus offers a variety of enormously fascinating types of games.
    It can even be said to be a game considering the largest variety of types compared to other game categories.

    Slot machines that used to pretense mechanically have now been transformed into money-making machines past hundreds or even thousands of
    titles that have been published on the subject of the world and played by millions of people from various countries.
    Who would have thought that a machine that was considered a failure by its creators would become a major
    phenomenon in the online gambling industry.

    You craving to know that this online slot machine was created by
    an inventor of French descent who lives in the allied States.
    At first he wanted to create a machine that could automate the
    poker gambling game fittingly that there was no longer a infatuation for a
    dealer to relieve the players. However, it turned out that this robot was considered a failure because it
    could not play-act properly.

    That was the stock of slot machines that you can find upon online gambling sites upon the internet.
    In this article we will discuss the Maboswayevent site, an online gambling site
    that provides various types of the best online slot gambling games upon the market.

    upon this site you can find hundreds of types of online slot games from various famous providers more
    or less the world.

    In addition, we will after that discuss some tips and behavior for winning online slot gambling games in an easy way.
    So, for those of you who want to belong to in online slot games, keep an eye on the taking into consideration explanation.


Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.