<< Chapter < Page Chapter >> Page >
Illustration shows that the ball-shaped end of the humerus fits into the socket in the shoulder joint.
The shoulder joint is an example of a ball-and-socket joint.

Watch this animation showing the six types of synovial joints.

Career connection

Rheumatologist

Rheumatologists are medical doctors who specialize in the diagnosis and treatment of disorders of the joints, muscles, and bones. They diagnose and treat diseases such as arthritis, musculoskeletal disorders, osteoporosis, and autoimmune diseases such as ankylosing spondylitis and rheumatoid arthritis.

Rheumatoid arthritis (RA) is an inflammatory disorder that primarily affects the synovial joints of the hands, feet, and cervical spine. Affected joints become swollen, stiff, and painful. Although it is known that RA is an autoimmune disease in which the body’s immune system mistakenly attacks healthy tissue, the cause of RA remains unknown. Immune cells from the blood enter joints and the synovium causing cartilage breakdown, swelling, and inflammation of the joint lining. Breakdown of cartilage causes bones to rub against each other causing pain. RA is more common in women than men and the age of onset is usually 40–50 years of age.

Rheumatologists can diagnose RA on the basis of symptoms such as joint inflammation and pain, X-ray and MRI imaging, and blood tests. Arthrography is a type of medical imaging of joints that uses a contrast agent, such as a dye, that is opaque to X-rays. This allows the soft tissue structures of joints—such as cartilage, tendons, and ligaments—to be visualized. An arthrogram differs from a regular X-ray by showing the surface of soft tissues lining the joint in addition to joint bones. An arthrogram allows early degenerative changes in joint cartilage to be detected before bones become affected.

There is currently no cure for RA; however, rheumatologists have a number of treatment options available. Early stages can be treated with rest of the affected joints by using a cane or by using joint splints that minimize inflammation. When inflammation has decreased, exercise can be used to strengthen the muscles that surround the joint and to maintain joint flexibility. If joint damage is more extensive, medications can be used to relieve pain and decrease inflammation. Anti-inflammatory drugs such as aspirin, topical pain relievers, and corticosteroid injections may be used. Surgery may be required in cases in which joint damage is severe.

Section summary

The structural classification of joints divides them into bony, fibrous, cartilaginous, and synovial joints. The bones of fibrous joints are held together by fibrous connective tissue; the three types of fibrous joints are sutures, syndesomes, and gomphoses. Cartilaginous joints are joints in which the bones are connected by cartilage; the two types of cartilaginous joints are synchondroses and symphyses. Synovial joints are joints that have a space between the adjoining bones. The functional classification divides joints into three categories: synarthroses, amphiarthroses, and diarthroses. The movement of synovial joints can be classified as one of four different types: gliding, angular, rotational, or special movement. Gliding movements occur as relatively flat bone surfaces move past each other. Angular movements are produced when the angle between the bones of a joint changes. Rotational movement is the movement of a bone as it rotates around its own longitudinal axis. Special movements include inversion, eversion, protraction, retraction, elevation, depression, dorsiflexion, plantar flexion, supination, pronation, and opposition. Synovial joints are also classified into six different categories on the basis of the shape and structure of the joint: planar, hinge, pivot, condyloid, saddle, and ball-and-socket.

Questions & Answers

Describe how hormones regulate blood pressure, blood volume, and kidney function
junius Reply
2 Positive water potential is placed on the left side of the tube by increasing Ψp such that the water level rises on the right side. Could you equalize the water level on each side of the tube by adding solute, and if so, how?
Sarah Reply
plant and animal cell
Oyedeji Reply
what plant and animal cell
PAvan
plant cell has a definite shape whilst the animal cell has indefinite shape
Owusu
what are the type of cell
abiola Reply
Poukaryotic cell and euakaryotic cell
Smile's
Which of the following is considered a keystone species? Deer, Beaver, Elk or Wolves
Nicole Reply
Origin and Diversity of higher plants
Gideon Reply
explain the reason why the impudent and excessive use of antibiotics could be potentially harmful to the user.
Alfred Reply
diseases gain antibiotic resistance from the antibiotic if often used.
Jerome
what is mean by serum
vasant Reply
what is D glucose n L glucose
Moses Reply
explain the mechanism and pathway of moving a water molecule from soil solution to atmosphere through a dicot plant
Bumali Reply
different types of white blood cells and their functions
Yolanda Reply
the different types of blood cells and their functions
Musa
how many electrons do elements in groups 14 and 17 need to gain to achieve a stable configuration
Porridge96 Reply
how the brain responses the different impulses coming from the receptors
Abdul-Rahim Reply
which cell structure does mitotic spindle arise
jeffrey Reply
a heterozygous tall pea plant is crossed with a short pea plant
Moses Reply

Get the best Biology course in your pocket!





Source:  OpenStax, Biology. OpenStax CNX. Feb 29, 2016 Download for free at http://cnx.org/content/col11448/1.10
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Biology' conversation and receive update notifications?

Ask