joints

Question 1

What are the two ways to classify joints?

Answer 1

• Structural
• Functional

Structural classification is based on the structure connecting the articulating surfaces, while functional classification is based on the amount of movement.

Question 2

What are the three types of structural classification of joints?

Answer 2

• Fibrous
• Cartilaginous
• Synovial

Synovial joints are the most common type.

Question 3

What is the functional classification for a joint that allows little to no movement?

Answer 3

Synarthrosis

An example is the sutures of the skull.

Question 4

What is the functional classification for a joint that allows slight movement?

Answer 4

Amphiarthrosis

Examples include the pubic symphysis and intervertebral discs.

Question 5

What is the functional classification for a joint that allows significant movement?

Answer 5

Diarthrosis

Synovial joints are classified as diarthroses.

Question 6

What are the three categories of diarthrosis based on axes of motion?

Answer 6

• Uniaxial
• Biaxial
• Multiaxial

Examples include the elbow (uniaxial), metacarpophalangeal joints (biaxial), and hip and shoulder joints (multiaxial).

Question 7

What are the characteristics of fibrous joints?

Answer 7

• No joint cavity
• Bones held together by dense connective tissue
• Permit little to no movement

Types include sutures, syndesmoses, and gomphoses.

Question 8

What type of fibrous joint joins the bones of the skull?

Answer 8

Sutures

Classified as synarthroses, some may allow slight movement.

Question 9

What type of fibrous joint joins two parallel bones using fibrous connective tissue?

Answer 9

Syndesmoses

Functionally classified as amphiarthroses.

Question 10

What type of fibrous joint anchors teeth to the maxilla and mandible?

Answer 10

Gomphoses

Made of periodontal ligaments.

Question 11

What are the characteristics of cartilaginous joints?

Answer 11

• Bones joined by hyaline cartilage or fibrocartilage
• Synchondroses and symphyses

Synchondroses are joined by hyaline cartilage, while symphyses are joined by fibrocartilage.

Question 12

What is an example of a synchondroses joint?

Answer 12

Epiphyseal plates

Found in long bones early in life to allow growth.

Question 13

What is an example of a symphyses joint?

Answer 13

• Pubic symphysis
• Intervertebral symphyses

These joints permit strong attachment while allowing limited movement.

Question 14

What are the characteristics of synovial joints?

Answer 14

• Contain a joint cavity
• Bones do not directly touch
• Articular capsule and ligaments

Classified as diarthroses.

Question 15

What is the function of the synovial membrane?

Answer 15

Secretes synovial fluid

Lubricates the joint and nourishes cartilage.

Question 16

What are the types of synovial joints based on their movement?

Answer 16

• Pivot
• Hinge
• Condyloid
• Saddle
• Plane
• Ball-and-socket

Each type allows different ranges and types of motion.

Question 17

What type of joint is the elbow?

Answer 17

Hinge joint

Allows flexion and extension.

Question 18

What type of joint is the shoulder?

Answer 18

Ball-and-socket joint

Allows a large range of motion.

Question 19

What is arthritis?

Answer 19

Inflammation of a joint

Leads to pain, swelling, stiffness, and reduced mobility.

Question 20

What is the most common form of arthritis?

Answer 20

Osteoarthritis

Caused by degeneration of articular cartilage.

Question 21

What is the purpose of hip replacement surgery?

Answer 21

To alleviate pain in severely arthritic joints

It replaces the articular surfaces of the bones with artificial materials.

Question 22

What is flexion?

Answer 22

Reduces the angle of the joint from resting position

Opposite of extension.

Question 23

What is abduction?

Answer 23

Moves a limb away from midline of body

Opposite of adduction.

Question 24

What is supination?

Answer 24

Moves palm to face anteriorly

Opposite of pronation.

Question 25

What is **dorsiflexion**?

Answer 25

Moves top of foot toward anterior leg ## Footnote Opposite of plantar flexion.

Question 26

What is **inversion**?

Answer 26

Turns bottom of foot toward midline ## Footnote Opposite of eversion.

Question 27

What is **protraction**?

Answer 27

Jaw is pushed forward ## Footnote Opposite of retraction.

Question 28

What is **elevation**?

Answer 28

Upward movement ## Footnote Opposite of depression.

Question 29

What is **opposition**?

Answer 29

Moves tip of thumb in contact with a finger ## Footnote Opposite of reposition.

Question 30

What is the **joint type** of the **temporomandibular joint**?

Answer 30

Hinge joint ## Footnote Allows depression/elevation, excursion, and protraction/retraction of the mandible.

Question 31

The **shoulder joint** is classified as what type of joint?

Answer 31

Ball-and-socket joint ## Footnote Allows a large range of motion including flexion, extension, hyperextension, abduction, adduction, medial and lateral rotation, circumduction.

Question 32

What bones articulate to form the **elbow joint**?

Answer 32

Humerus, radius, and ulna ## Footnote Hinge joint that allows flexion and extension of the forearm.

Question 33

What ligaments strengthen the **elbow joint**?

Answer 33

* Radial collateral ligaments * Ulnar collateral ligaments ## Footnote These ligaments prevent side-to-side movements.

Question 34

The **hip joint** is formed by the articulation of which two structures?

Answer 34

Acetabulum and head of femur ## Footnote Ball-and-socket joint with a lesser range of motion than the shoulder, favoring strength and stability.

Question 35

What are the main functions of the **knee joint**?

Answer 35

* Allows flexion and extension of the leg * Provides support and cushioning ## Footnote Involves articulation of femur, tibia, and patella, with medial and lateral meniscus and cruciate ligaments.

Question 36

Which major joints are classified as **hinge joints**?

Answer 36

* Knee joint * Elbow joint ## Footnote A and B are correct. The shoulder joint and hip joint are not hinge joints.

Question 37

What is the **summary** of the chapter's learning objectives?

Answer 37

* Discuss the structural classification of joints * Discuss the functional classification of joints * Discuss the movements that occur at joints * Describe the components of major joints ## Footnote These objectives guide the understanding of joint anatomy and function.