The pelvic girdle transfers upper body weight to the lower limbs by articulating with the spine. Malformations may distort the appearance of the surrounding body structures such as the buttocks, but more importantly can interfere with weight bearing and ambulation.
Malformations may affect any of the bones or joints of the two girdles. Access to the complete content on Oxford Medicine Online requires a subscription or purchase. Public users are able to search the site and view the abstracts for each book and chapter without a subscription. Please subscribe or login to access full text content. If you have purchased a print title that contains an access token, please see the token for information about how to register your code. For questions on access or troubleshooting, please check our FAQs , and if you can't find the answer there, please contact us.
All Rights Reserved. Under the terms of the licence agreement, an individual user may print out a PDF of a single chapter of a title in Oxford Medicine Online for personal use for details see Privacy Policy and Legal Notice. Oxford Medicine Online. Publications Pages Publications Pages. Recently viewed 0 Save Search. Human Malformations and Related Anomalies 3 ed. The ilium is the fan-like, superior region that forms the largest part of the hip bone.
It is firmly united to the sacrum at the largely immobile sacroiliac joint see Figure 6. The ischium forms the posteroinferior region of each hip bone. It supports the body when sitting. The pubis forms the anterior portion of the hip bone. The pubis curves medially, where it joins to the pubis of the opposite hip bone at a specialized joint called the pubic symphysis.
The three areas of each hip bone, the ilium, pubis, and ischium, converge centrally to form a deep, cup-shaped cavity called the acetabulum.
This is located on the lateral side of the hip bone and is part of the hip joint. The large opening in the anteroinferior hip bone between the ischium and pubis is the obturator foramen. This space is largely filled in by a layer of connective tissue and serves for the attachment of muscles on both its internal and external surfaces. The differences between the adult female and male pelvis relate to function and body size. The greater sciatic notch of the male hip bone is narrower and deeper than the broader notch of females.
Because the female pelvis is adapted for childbirth, it is wider than the male pelvis, as evidenced by the distance between the anterior superior iliac spines see Figure 6.
The ischial tuberosities of females are also farther apart, which increases the size of the pelvic outlet. Because of this increased pelvic width, the subpubic angle is larger in females greater than 80 degrees than it is in males less than 70 degrees. The female sacrum is wider, shorter, and less curved, and the sacral promontory projects less into the pelvic cavity, thus giving the female pelvic inlet pelvic brim a more rounded or oval shape compared to males.
Pectoral girdle has two bones, namely clavicle and scapula. In humans, the left and right pectoral girdle can function independently because they both do not act as a unit, i. The axial skeleton coordinates the functioning of both the pectoral girdles. Clavicle: It is a collar bone, which appears S-shaped.
It lies in an anterior side of the shoulder. It is the longest bone, which lies horizontally. Clavicle laterally supports the scapula, as the lateral end of the clavicle is joined to the posterior ridge of the scapula coracoid process via coracoclavicular ligament. It possesses three regions like the sternal end, acromial end and shaft. Scapula: It is also termed as shoulder blade or blade bone, which lies a posterior side of the shoulder.
Scapula possesses two ridges, namely the coracoid process and spine of the scapula. There are three depressions called fossae , in which two fossae supraspinous fossa and infraspinous fossa are present posteriorly, and one fossa subscapular fossa is present towards the anterior side.
Fossae increase the surface area for the forelimbs attachment. It is defined as the bone connecting the hindlimbs to the axial skeleton. Unlike pectoral girdle, it only comprises hip bones or coxal bones. In humans, there are two hip bones. Coxal bones serve as an attachment point of both the hind limbs. Thus, it serves as a strong base above which the upper body rests.
0コメント