Question

1. List and explain in your own words the 4 types of joints.
   1. List and describe, in your own words, each category under each type.
   2. Give an example for each category (try and avoid one that is listed in the handout)
   3. Draw each of your examples (except for the categories under synovial joints)

Answer 1

Answer :

A joint or articulation (or articular surface) is the connection made between bones in the body which link the skeletal system into a functional whole. They are constructed to allow for different degrees and types of movement. Some joints, such as the knee, elbow, and shoulder, are self-lubricating, almost frictionless, and are able to withstand compression and maintain heavy loads while still executing smooth and precise movements.

There are four structural classifications of joints:

1.fibrous joint – joined by dense regular connective tissue that is rich in collagen fibers.

Examples of fibrous joints include: sutures between skull bones, syndesmoses between certain long bones e.g. the tibia and fibula. gomphoses that attach the roots of human teeth to the upper- and lower- jaw bones.

2.cartilaginous joint – joined by cartilage. There are two types: primary cartilaginous joints composed of hyaline cartilage, and secondary cartilaginous joints composed of hyaline cartilage covering the articular surfaces of the involved bones with fibrocartilage connecting them.

The joint between the manubrium and the sternum is an example of a cartilaginous joint. This type of joint also forms the growth regions of immature long bones and the intervertebral discs of the spinal column.

3.synovial joint – not directly joined – the bones have a synovial cavity and are united by the dense irregular connective tissue that forms the articular capsule that is normally associated with accessory ligaments.

The six types of synovial joints are the pivot, hinge, saddle, plane, condyloid, and ball-and-socket joints. Pivot joints are found in your neck vertebrae, while hinge joints are located in your elbows, fingers, and knees. Condyloid joints form the connection between your lower arm and wrist.

4.facet joint – joint between two articular processes between two vertebrae.

There are two facet joints in each spinal motion segment and each facet joint is innervated by the recurrent meningeal nerves. In the lumbar spine, for example, the facet joints function to protect the motion segment from anterior shear forces, excessive rotation and flexion.