There is less movement between the synchondrosis joints. Therefore, permanent joints are more stable due to this factor. Symphysis is the second type of cartilaginous joint where the fibrocartilage joins two bones. It is stronger in nature in comparison to the synchondrosis. The strength of the symphysis is more stable because it contains many bundles of very thick collagen fibres. Thus, this gives the structure more resistance and it resists the pulling and the bending forces.
Due to the high rigidity, the movement between the bones is hindered. The distribution of the symphysis is seen in the pubic portions of the right and left hip bones. It is also present in the site which unites the manubrium to the sternum. The symphysis joints are also distributed in between vertebrae of the vertebral column. The characteristic feature of the symphysis joints located at the vertebral column provides strength to withstand the shock created on the vertebral column.
Synchondrosis and symphysis are two types of joints which are cartilaginous in nature. Since both joints are cartilaginous, the principle factor of differentiation is the type of cartilage.
Thus, the key difference between synchondrosis and symphysis is that synchondrosis joints will have hyaline cartilage while symphysis joints will have fibrocartilage. Due to this differentiation in the type of cartilage, the individual properties of the two types of junctions also differ in terms of their movement, rigidity, flexibility and strength.
The below infographic summarizes the difference between synchondrosis and symphysis. Examples of permanent synchondroses are found in the thoracic cage. One example is the first sternocostal joint, where the first rib is anchored to the manubrium by its costal cartilage.
The articulations of the remaining costal cartilages to the sternum are all synovial joints. Additional synchondroses are formed where the anterior end of the other 11 ribs is joined to its costal cartilage. Unlike the temporary synchondroses of the epiphyseal plate, these permanent synchondroses retain their hyaline cartilage and thus do not ossify with age.
Due to the lack of movement between the bone and cartilage, both temporary and permanent synchondroses are functionally classified as a synarthrosis.
Fibrocartilage is very strong because it contains numerous bundles of thick collagen fibers, thus giving it a much greater ability to resist pulling and bending forces when compared with hyaline cartilage. This gives symphyses the ability to strongly unite the adjacent bones, but can still allow for limited movement to occur. Thus, a symphysis is functionally classified as an amphiarthrosis. The gap separating the bones at a symphysis may be narrow or wide.
Examples in which the gap between the bones is narrow include the pubic symphysis and the manubriosternal joint. At the pubic symphysis, the pubic portions of the right and left hip bones of the pelvis are joined together by fibrocartilage across a narrow gap. Similarly, at the manubriosternal joint, fibrocartilage unites the manubrium and body portions of the sternum.
The intervertebral symphysis is a wide symphysis located between the bodies of adjacent vertebrae of the vertebral column. Here a thick pad of fibrocartilage called an intervertebral disc strongly unites the adjacent vertebrae by filling the gap between them. The width of the intervertebral symphysis is important because it allows for small movements between the adjacent vertebrae.
In addition, the thick intervertebral disc provides cushioning between the vertebrae, which is important when carrying heavy objects or during high-impact activities such as running or jumping. A synchondrosis is formed when the adjacent bones are united by hyaline cartilage. A temporary synchondrosis is formed by the epiphyseal plate of a growing long bone, which is lost when the epiphyseal plate ossifies as the bone reaches maturity. The synchondrosis is thus replaced by a synostosis. Permanent synchondroses that do not ossify are found at the first sternocostal joint and between the anterior ends of the bony ribs and the junction with their costal cartilage.
A symphysis is where the bones are joined by fibrocartilage and the gap between the bones may be narrow or wide. A narrow symphysis is found at the manubriosternal joint and at the pubic symphysis. Updating… Please wait. Unable to process the form. Check for errors and try again. Thank you for updating your details. Log In. Sign Up. Become a Gold Supporter and see no ads. Log in Sign up. Articles Cases Courses Quiz. About Recent Edits Go ad-free. Edit article. View revision history Report problem with Article.
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