Bony Joints Synostoses

A bony joint, or synostosis8 (SIN-oss-TOE-sis), is a joint in which two bones, once separate, have become fused by osseous tissue and in most cases are then regarded as a single bone. Some fibrous and cartilaginous joints ossify with age—that is, the gap between adjacent bones becomes filled with osseous tissue until the two bones appear as one. In the skull, for example, both the frontal bone and mandible are represented at birth by separate right and left bones; in early childhood, these bones become fused. In old age, some sutures become obliterated by ossification and adjacent cranial bones fuse seamlessly together. The epiphyses and dia-physes of the long bones are joined by cartilaginous joints in childhood and adolescence, and these become synos-toses in early adulthood. The attachment of the first rib to the sternum also becomes a synostosis with age.

_Think About It_

The intervertebral joints are symphyses only in the cervical through the lumbar region. How would you classify the intervertebral joints of the sacrum and coccyx in a middle-aged adult?

6syn = together + chondr = cartilage + osis = condition

7 sym = together + physis = growth

Saladin: Anatomy & I 9. Joints I Text I I © The McGraw-Hill

Physiology: The Unity of Companies, 2003 Form and Function, Third Edition

298 Part Two Support and Movement

298 Part Two Support and Movement

Cartilaginous Joints

Figure 9.5 Cartilaginous Joints. (a) Synchondroses, represented by costal cartilages joining the ribs to the sternum; (b) the pubic symphysis; (c) intervertebral discs, which join adjacent vertebrae to each other by symphyses. What is the difference between the pubic symphysis and the interpubic disc?

Figure 9.5 Cartilaginous Joints. (a) Synchondroses, represented by costal cartilages joining the ribs to the sternum; (b) the pubic symphysis; (c) intervertebral discs, which join adjacent vertebrae to each other by symphyses. What is the difference between the pubic symphysis and the interpubic disc?

Before You Go On

Answer the following questions to test your understanding of the preceding section:

  1. Define suture, gomphosis, and syndesmosis, and explain what these three joints have in common.
  2. Name the three types of sutures and describe how they differ.
  3. Name two synchondroses and two symphyses.
  4. Give some examples of joints that become synostoses with age.

Was this article helpful?

0 0
Essentials of Human Physiology

Essentials of Human Physiology

This ebook provides an introductory explanation of the workings of the human body, with an effort to draw connections between the body systems and explain their interdependencies. A framework for the book is homeostasis and how the body maintains balance within each system. This is intended as a first introduction to physiology for a college-level course.

Get My Free Ebook


Responses

  • Maarit Ruoho
    Which joints becomes a synostosis?
    7 years ago
  • Berhane Robel
    Which of the following examples represents a bony joint, or synostosis?
    7 years ago
  • Welde Muhammed
    How would you classify the intervertebral joints of the sacrum and coccyx symphyses?
    7 years ago
  • Jan
    Where do you find cartilaginous joints?
    7 years ago
  • GLENN HUNTER
    What is bony joints or synostosis?
    6 years ago
  • stefan
    What bony joint is two bones fused together?
    6 years ago
  • GHENET
    Which of the following is NOT an example of a cartilaginous joint?
    6 years ago
  • Arsenio
    Do sutures become synostoses?
    6 years ago
  • willis
    Which type of joint becomes ossified with age and becomes a synostosis?
    6 years ago
  • ezio
    How do you classify middle aged adult sacrum and coccyx?
    5 years ago
  • SEGAN
    How would you classify intervertebral joints of sacrum and coccyx in a middle aged adult?
    5 years ago
  • sirja ahtisaari
    Which of the following examples represent a bony joint or syntosis?
    4 years ago
  • ignazio castiglione
    How would you classify the intervetebral joints of the sacrum and coccyx?
    4 years ago
  • MICHELLE
    Which joints are synostoses?
    2 years ago
  • temshe biniam
    Where is the Synostosis the human body?
    2 years ago
  • kalle saisio
    Which types of joints may form synostoses during normal growth and development?
    11 months ago
  • tolman
    Do people have different numbers of bony joints in coccyx?
    8 months ago
  • Durante
    Is the sacrum sutured or synostoses?
    6 months ago

Post a comment