Unit 13: Joints

Question 1

the human body has 206 bones, aside from the hyoid bone, all the rest are?

Answer 1

connected to at least one other bone.

Question 2

what are joints?

Answer 2

joints/articulations are locations where the bones or bones and cartilage come together.

Question 3

joints allow for?

Answer 3

movement between the bones.

Question 4

stable joints allow for how much movement?

Answer 4

stable joints allow for little to no mobility and joints that provide the most movement are least stable.

Question 5

3 structural classifications of joints?

Answer 5

1. fibrous joint: bones are united by fibrous connective tissue.
2. cartilaginous joint: bones are united by hyaline cartilage or fibrocartilage
3. synovial joint: bones are not directly connected but come into contact with eachother within a joint cavity that is filled with lubricating fluid.

Question 6

which joints allow for free movement between bones?

Answer 6

synovial joints

Question 7

which are the most common joints of the body?

Answer 7

synovial joints

Question 8

functional classification of joints is classified by?

Answer 8

the amount of mobility found between the bones.
- synarthrosis/immobile joint
- amphiarthrosis/slightly moveable joint
- diarthrosis/freely moveable joint

Question 9

synarthrosis?

Answer 9

an immobile joint is called a synarthrosis.
- strong union between the bones
- needed where protection is needed for internal organs
- EXAMPLE: sutures

Question 10

amphiarthrosis?

Answer 10

a joint that has limited mobility.
- EXAMPLE: intervertebral discs, pubic symphysis.

Question 11

diarthrosis?

Answer 11

a joint that is able to move freely.
- all synovial joints of the body are diarthrosis.
- most diarthrotic joints are found in the appendicular skeleton giving the limbs a wide range of motion.

Question 12

multiaxial movement of a joint?

Answer 12

multiaxial diarthrotic joint allows for movement along 3 axis.
- EXAMPLE: hip and shoulder joint

Question 13

3 types of fibrous joints?

Answer 13

1. sutures
2. syndesmoses
3. gomphosis

Question 14

what is a fibrous joint?

Answer 14

a fibrous joint is one that is directly connected to eachother by fibrous connective tissue.

Question 15

all the bones of the skull except the mandible are joined by?

Answer 15

fibrous joints called sutures.
- synarthrosis/immoveable
- at birth the frontal and maxillary bones consist of right and left halves joined by sutures, they then fuse together to form one bone.

Question 16

whats a syndesmosis?

Answer 16

a syndesmosis is a type of fibrous joint in which two parallel bones are united by fibrous connective tissue called interosseous membrane.
- shafts of the radius and ulna and shafts of the tibia and fibula

Question 17

what is a gomphosis?

Answer 17

fibrous joint that anchors the root of a tooth into its bony socket in the maxilla or mandible.
- synarthrosis

Question 18

what is a cartilaginous joint and what are the two types of cartilaginous joints?

Answer 18

a cartilaginous joint is where the bones are united by cartilage.
- joined by fibrocartilage or hyaline cartilage
1. synchondrosis
2. symphysis

Question 19

synchondrosis?

Answer 19

where bones are joined by hyaline cartilage.
- temporary synchondrosis is the epiphyseal plate in the long bone.
- permanent synchondrosis is the sternocostal joint where the rib is anchored to the manubrium by its costal cartilage.
- synarthrosis

Question 20

symphysis?

Answer 20

joined by fibrocartilage
- very strong because it has a lot of thick collagen fibers
- amphiarthrosis
example: pubic symphysis and intervertebral symphysis

Question 21

what are synovial joints and what are the different types?

Answer 21

synovial joints are the most common and the difference between this and other joints is the presence of JOINT CAVITY.
- they are also not connected directly with fibrous connective tissue or cartilage which gives the ability of the bones to move smoothly against eachother.

Question 22

what is the articular capsule?

Answer 22

connective tissue structure that encloses the joint cavity of a synovial joint

Question 23

what is the articular cartilage?

Answer 23

thin layer of cartilage covering the epiphysis reducing friction and acts as a shock absorber

Question 24

what is the synovial membrane?

Answer 24

the synovial membrane is the thin membrane that lines the inner part of the joint cavity and secretes synovial fluid

Question 25

what is synovial fluid?

Answer 25

thick lubricating fluid that fills in the interior of a synovial joint

Question 26

what movement are synovial joints?

Answer 26

diarthrosis.

Question 27

whats an articular disc?

Answer 27

articular disc aka meniscus in certain joints.
- fibrocartilage pad that provides cushioning between bones
- meniscus is specifically found in the knee joint: c shaped structure

Question 28

what is a bursa?

Answer 28

fluid filled sac near joints where friction may occur/

Question 29

types of synovial joints?

Answer 29

1. pivot
2. hinge
3. condyloid/ellipsoid
4. saddle
5. plane
6. ball and socket

Question 30

what is a pivot joint and examples?

Answer 30

at a pivot joint, the rounded portion of a bone is enclosed in a ring formed by another bone.
- uniaxial joint: one axis movement
- EXAMPLE: atlantoaxial joint

Question 31

what is a hinge joint?

Answer 31

the convex end of one bone articulates with the concave end of the other bone
- uniaxial joint
- EXAMPLE: elbow joint, knee joint, ankle

Question 32

what is a condyloid joint?

Answer 32

aka ellipsoid joint
the shallow depression at the end of one bone articulates with a rounded structure of another bone.
- biaxial joint: two axis
- radiocarpal joint

Question 33

what is a saddle joint?

Answer 33

when both of the articulating surfaces for the bones have a saddle shape which is concave in one direction and convex in the other.
- biaxial joint: two axis
- carpometacarpal joint

Question 34

what is a plane joint?

Answer 34

the articulating surfaces of the bones are flat or curved, gliding movement
- multiaxial but not all
- carpal bones tarsal bones, clavicle/scapula

Question 35

what is a ball and socket joint?

Answer 35

• greatest rom
• the rounded end of a bone fits into the concave end of another bone
• multiaxial
• hip joint, shoulder joint