Joint Structure

Question 1

Name the 2 major classifications of joints

Answer 1

• diarthrosis (synovial jt)
• synarthrosis

Question 2

Which classification of joints is mobile?

Answer 2

diarthrosis

Question 3

Synarthroses that have some motion are called ____

Answer 3

amphiarthroses

Question 4

Name the subclassifications of diarthroses by type of movement

Answer 4

• Uniaxial
• Biaxial
• Polyaxial (3 axes)
• Plane (flat jt)

Question 5

What are some examples of uniaxial joints?

Answer 5

• ulnohumeral jt
• proximal & distal radioulnar jts

Question 6

What is an example of a biaxial joint?

Answer 6

radiocarpal jt

Question 7

A hinge joint is an example of what type of diarthrodial joint?

Answer 7

uniaxial

Question 8

A gliding joint is an example of what type of diarthrodial joint?

Answer 8

uniaxial (1 axis)

Question 9

A joint that does flexion, extension, abduction and adduction is an example of what type of diarthrodial joint?

Answer 9

biaxial (2 axes)

Question 10

What are some examples of polyaxial joints?

Answer 10

• shoulder
• hip

Question 11

What are some examples of plane joints?

Answer 11

• zyapophyseal
• patellofemoral
• carpals/tarsals

Question 12

What type of diarthrodial joint has the most motion and least stability relative to other types of joints?

Answer 12

polyaxial (3 axes)

Question 13

What are the subclassifications of synarthrodial joints?

Answer 13

• symphysis
• suture
• synchondrosis
• syndesmosis
• synostosis

Question 14

Describe the structure of a symphysis

Answer 14

fibrocartilage & ligaments

Question 15

Describe the structure of a suture

Answer 15

interdigitating bones with ligamentous connections

Question 16

Describe the structure of a synchondrosis

Answer 16

structures with cartilage ends, but no synovium

Question 17

Describe the structure of a syndesmosis

Answer 17

fibrous connections between bones without cartilage

Question 18

Describe the structure of a synostosis

Answer 18

normal variant or pathological fusion of bones

Question 19

Name an example of a symphysis

Answer 19

• pubic symphysis
• IVDs

Question 20

Name an example of a suture

Answer 20

skull

Question 21

Name an example of a synchondrosis

Answer 21

• manubriosternal
• costochondral

Question 22

Name an example of a syndesmosis

Answer 22

interosseous membrane at:
- tibiofibular jt
- radioulnar jt

Question 23

Name an example of a normal synostosis

Answer 23

5th toe synphalangism (DIP jt fusion)

Question 24

Name an example of a pathological synostosis

Answer 24

SI ankylosis in ankylosing spondylitis

Question 25

What type of synarthrodial joint is technically an amphiarthrosis?

Answer 25

symphysis (should allow limited motion)

Question 26

What type of synarthrodial joint would **not** be affected by rheumatoid arthritis?

Answer 26

synchondrosis (no synovium)

Question 27

A high ankle sprain affects what type of joint?

Answer 27

syndesmosis

Question 28

Inflammation of the spine resulting in fusion of joints is an example of what type of joint?

Answer 28

pathological synostosis (ankylosing spondylitis)

Question 29

A closed physis is called a ____

Answer 29

physeal scar

Question 30

What usually covers the articular ends of synovial joints?

Answer 30

hyaline cartilage

Question 31

What is the term for the ligamentous sleeve that holds bones together?

Answer 31

joint capsule

Question 32

What is the bare area of a joint?

Answer 32

space between where cartilage ends and synovium begins (bone only)

Question 33

During development, if the notochord does not separate into the anterior spinal elements, what type of joint is formed?

Answer 33

synostosis (congenital fusion)

Question 34

What is ankylosing spondylitis?

Answer 34

inflammation of the spine results in fusion

Question 35

The action of pronation & supination is done by what type of joint?

Answer 35

uniaxial diarthrodial

Question 36

What is the function of facet joints and what type of joint are they?

Answer 36

- limit motion in certain planes - plane (flat) joint

Question 37

What type of joint are the medial and lateral facets of the patellofemoral joint?

Answer 37

plane (flat) joint

Question 38

What type of synarthrodial joint allows the most amount of motion?

Answer 38

symphysis (technically an amphiarthrosis)

Question 39

Which joint would **not** be affected by rheumatoid arthritis? A) ulnohumeral B) tibiofibular C) manubriosternal D) pubic symphysis

Answer 39

manubriosternal (synchondrosis)

Question 40

What is a "trauma case"?

Answer 40

a soft tissue injury that happens to have an associated fracture (more concerned about damaged soft tissues than broken bones)

Question 41

What type of joint is of particular concern in trauma cases?

Answer 41

syndesmosis (eg. high ankle sprain, monteggia Fx)

Question 42

What is a Monteggia fracture and what type of joint does it concern?

Answer 42

fracture of the ulna with dislocation of radial head from proximal radioulnar joint (damages interosseous membrane - syndesmosis)

Question 43

The articular end of a bone is called the ____

Answer 43

epiphysis

Question 44

Where does the synovium end?

Answer 44

Where joint capsule meets bone

Question 45

What can happen to the bare area of a joint with Rheumatoid arthritis?

Answer 45

- rheumatoid arth. = inflammation of synovium - inflamed synovium pressing against bare area rapidly erodes bone, causing **marginal erosion**

Question 46

What part of the bone has the richest vascular beds?

Answer 46

metaphysis (most metabolically active)

Question 47

Where does the epiphysis get its blood supply from?

Answer 47

vascular bed from metaphysis

Question 48

What creates nutrition for articular cartilage of a joint?

Answer 48

vascular bed of epiphysis creates nutrition via diffusion (no BVs directly feed articular cartilage)