Pubic symphysis is what kind of joint

Review Questions. Critical Thinking Questions 1. Explain how degree of mobility is related to joint strength. Solutions Answers for Critical Thinking Questions Functional classification of joints is based on the degree of mobility exhibited by the joint.

A synarthrosis is an immobile or nearly immobile joint. An example is the epiphyseal plate or the joints between the skull bones surrounding the brain. An amphiarthrosis is a slightly moveable joint, such as the pubic symphysis or an intervertebral cartilaginous joint. A diarthrosis is a freely moveable joint. These are subdivided into three categories. A uniaxial diarthrosis allows movement within a single anatomical plane or axis of motion. The elbow joint is an example.

A biaxial diarthrosis, such as the metacarpophalangeal joint, allows for movement along two planes or axes. The hip and shoulder joints are examples of a multiaxial diarthrosis. These allow movements along three planes or axes. Joint mobility is inversely related to joint strength. A synarthrosis, which is an immobile joint, serves to strongly connect bones thus protecting internal organs such as the heart or brain.

A slightly moveable amphiarthrosis provides for small movements while maintaining stability between adjacent bones as in the vertebral column. The freedom of movement provided by a diarthrosis can allow for large movements, such as is seen with most joints of the limbs. However, these joints are the most frequently injured due to their looser articulations at the joint cavity.

Previous: 9. Next: 9. Share This Book Share on Twitter. A joint, also known as an articulation or articular surface, is a connection that occurs between bones in the skeletal system.

Joints provide the means for movement. The type and characteristics of a given joint determines its degree and type of movement. Joints can be classified based on structure and function. Structural classification of joints categorizes them based on the type of tissue involved in formation.

There are three structural classifications of joints: fibrous, cartilaginous, and synovial. Fibrous joints are connected by dense, tough connective tissue that is rich in collagen fibers. These fixed or immovable joints are typically interlocked with irregular edges.

There are three types of fibrous joints. Sutures are the types of joint found in the cranium skull. The nature of cranial sutures allows for some movement in the fetus.

However, they become mostly immovable as the individual ages, although very slight movement allows some necessary cranial elasticity. These rigid joints are referred to as synarthrodial. Syndesmoses are found between long bones of the body, such as the radio-ulnar and tibio-fibular joints. URL of Article. On this page:. Diseases of the pubis and pubic symphysis: MR imaging appearances. The adult human pubic symphysis: a systematic review. Clinically Oriented Anatomy.

Read it at Google Books - Find it at Amazon 4. Last's anatomy, regional and applied. Churchill Livingstone. Read it at Google Books - Find it at Amazon 5. Elsevier Health Sciences. Read it at Google Books - Find it at Amazon 6.

The discs consist of an outer annulus fibrosus that surrounds the inner nucleus pulposus. The annulus fibrosus and the nucleus pulposus distribute pressure evenly across the disc. The nucleus pulposus contains loose fibers suspended in a mucoprotein gel with the consistency of jelly. The disc can be likened to a jelly doughnut with the annulus fibrosis as the dough and the nucleus pulposis as the jelly.

If one presses down on the front of the doughnut, the jelly moves posteriorly. When one develops a prolapsed disc, the jelly the nucleus pulposus is forced out of the doughnut the disc and may put pressure on the nerve located near the disc, potentially causing symptoms of sciatica.

Diagram of Invertebral Disc : The lateral and superior view of an invertebral disc, including the vertebral body, intervertebral foramen, anulus fibrosis, and nucleus pulposus. Aging causes disc degeneration, in which the nucleus pulposus begins to dehydrate and the concentration of proteoglycans in the matrix decreases, limiting the ability of the disc to absorb shock. This general shrinking of disc size is partially responsible for the common decrease in height as humans age.

Learning Objectives Differentiate among the types of symphyses between two bones. Key Points Symphyses include the pubic symphysis and the intervertebral disc between two vertebrae, among others.

The pubic symphysis or symphysis pubis is the midline cartilaginous joint uniting the superior rami of the left and right pubic bones. It widens slightly whenever the legs are stretched far apart and can become dislocated.