Chapter 9: Articulations

In the skeletal system, a joint is the place of contact between what three pairs of things?

1. bone to bone

2. bone to cartilage

3. bone to teeth

What are the three structural categories of joints?

1. fibrous

2. cartilaginous

3. synovial

Which of the three structural categories of joints is being described here?

• no joint cavity

• occurs where bones are held together by dense regular (fibrous) CT

• connects ends of bones and bone parts

fibrous

Which of the three structural categories of joints is being described here?

• no joint cavity

• occurs where bones are joined by cartilage

• pad of cartilage wedged between the ends of bones

cartilaginous

Which of the three structural categories of joints is being described here?

• contains a fluid-filled joint cavity that separates the articulating surfaces of bones

• articulation surfaces enclosed in CT capsule

• bones attached to each other by various ligaments

• lined by synovial membrane

• contains synovial fluid

synovial

What are the three functional categories of joints?

1. synarthrosis

2. amphiarthrosis

3. diarthrosis

Which of the three functional categories of joints is being described here?

• immobile joint

• includes two types of fibrous joints and one type of cartilaginous joint

synarthrosis

Which of the three functional categories of joints is being described here?

• slightly mobile joint

• includes one type of fibrous joint and one type of cartilaginous joint

amphiarthrosis

Which of the three functional categories of joints is being described here?

• freely mobile joint

• includes all joints

diarthrosis

What is the relationship between mobility and stability of a joint?

more stable = less mobile (and vice versa)

Sutures are the ____ stable in comparison to other joints, but they are _________ because they hold two skull bones together.

most; immobile

Synovial joints, such as the ___________ (shoulder) and knee joints are the most ________of the joints, yet are the most unstable.

glenohumeral; mobile

Are all fibrous joints synarthroses (immobile joints)?

no

Which types of fibrous joints are synarthroses?

gomphoses and sutures

Besides two kinds of fibrous joints, what type of cartilaginous joint is synarthrosis?

synchondroses

What holds fibrous joints together?

dense regular (fibrous) CT

What is true about the joint cavity of fibrous joints?

There isn’t one.

The following examples fall under which structural category of joints?

• articulations of teeth in sockets

• sutures between skull bones

• articulations between the radius and ulna

• articulations between the tibia and fibula

fibrous

Where are the gomphoses located?

between a tooth and the jaw only

What type of movement do gomphoses allow?

none; they’re synarthroses

Where are sutures located?

only between certain bones of the skull

What is the function of sutures?

join skull bones and allow the skull to grow as the brain grows during childhood

The interosseous membrane between the radius and ulna has what purpose?

provides pivot where they can move against one another

What holds cartilaginous joints joints together?

cartilage (hyaline or fibrocartilage)

What is true about the joint cavity of cartilaginous joints?

There isn’t one.

Which type of cartilaginous joint is this?

* bones joined together by hyaline cartilage

synchondrosis

Which type of cartilaginous joint is this?

* pad of fibrocartilage between articulating bones

symphysis

Symphyses (type of cartilaginous joint) fall under which functional category?

amphiarthrosis

The pubic symphysis and intervertebral joints are examples of which kind of cartilaginous joint?

symphysis

Which structural category of joints do the following fall under?

1. glenohumeral (shoulder joint)

2. temporomandibular joint

3. elbow joint

4. knee joint

5. coxal (hip) joint

synovial

Are bones in synovial joints separated by a joint cavity?

yes

Synovial joints are made of a double-layered capsule called the _________ capsule.

articular

What kind of viscous, oily substance can be found in synovial joints?

synovial fluid

What does the synovial membrane produce?

synovial fluid

All articulating bone surfaced in the synovial joints are covered in _______ cartilage (which is a thin layer of hyaline cartilage).

articular

What are the basic features of synovial joints?

• articular capsule

• joint cavity

• synovial fluid

• articular cartilage

• ligaments

• nerves

• blood vessels

What are three purposes of synovial fluid in synovial joints?

1. lubricates articular cartilage on the surface of articulating bones

2. nourishes the articular cartilage’s chondrocytes

3. acts as a shock absorber, distributing stresses and force evenly across the articular surfaces when joint pressure suddenly increases

What is happening when a person cracks their knuckles?

bubbles in synovial fluid burst when a joint is stretched to a certain point, dropping the joint pressure lower