Joint Classifications

Question 1

Synarthroses (fibrous jts) include?

Answer 1

1. Suture
2. Syndesmosis
3. Gomphosis

Question 2

Suture

Answer 2

—Union of 2 bones by a ligament/membrane

—immobile jt

—Eventual fusion = synostosis

Question 3

Synostosis

Answer 3

Fusion of 2+ bones

Question 4

Syndesmosis

Answer 4

—Bone connected to bone by a dense fibrous membrane or cord (Tibia/fibula AND radius/ulna)

—Very little motion

Question 5

Gomphosis

Answer 5

—2 body surfaces connect as a peg in a hole

—The teeth and corresponding sockets in the mandible/maxilla are the only gomphosis jts in the body

Question 6

Amphiarthroses (Cartilaginous jts) include?

Answer 6

1. Synchrondrosis

2. Symphysis

Question 7

Synchondrosis (sternum and rib articulation)

Answer 7

—hyaline cartilage

— Cartilage adjoins 2 Ossifying centers of bones

—Provide stability during growth

— May ossify to a synostosis once growth is completed

—slight motion

Question 8

Symphysis

Answer 8

—generally located at the midline of the body

—2 bones covered with hyaline cartilage

—2 bones connected by fibrocartilage

—slight motion

Question 9

Diarthroses (synovial jts) include?

Answer 9

1. Uniaxial jt
2. Biaxial jt.
3. Multiracial jt.

Question 10

What five distinguished characteristics do Diarthroses joints have?

Answer 10

1. Jt cavity
2. Articular cartilage
3. Synovial membrane
4. Synovial fluid
5. Fibrous capsule

Question 11

T or F: Diarthroses joints are complex and vulnerable to injury?

Answer 11

True

Question 12

Uniaxial jt

Answer 12

One motion around a single axis in only plane of the body.

• hinge (ginglymus)—elbow jt
• pivot (torchoid)—atlantoaxial jt (AA)

Question 13

Biaxial Jt

Answer 13

Movement occurs in 2 planes and around 2 axes through convex/concave surfaces

• condyloid—MCP jt of finger
• Saddle—CMC jt of thumb

Question 14

Multi-axial jt

Answer 14

Movement occurs in 3 places and around 3 axes

• plane (gliding)—carpal jts
• Ball and socket—hip jt

Question 15

What are the 5 joint receptors?

Answer 15

1. Free Nerve endings
2. Pacinian Corpuscles
3. Golgi Ligament Endings
4. Ruffini Endings
5. Golgi-Mazzoni Corpuscles

Question 16

Location, sensitivity and Primary distribution of Free nerve endings

Answer 16

Location: Jt. Capsule; ligaments, synovium, fat pads

Sensitivity: 1 type is sensitive to non-noxious mechanical stress
The other type is sensitive to noxious mechanical or biomechanical stimuli

Distribution: All jts

Question 17

Pacinian Corpuscles location, sensitivity, distribuation?

Answer 17

Location: fibrous layer of jt. Capsule

Sensitivity: high frequency vibration, acceleration, and high velocity changes in jt position

Distribution: all jts

Question 18

Golgi ligament endings location, sensitivity, distribution?

Answer 18

Location: Ligaments, adjacent to ligaments’ bony attachment

Sensitivity: tension or stretch on ligaments

Distribution: Majority of jts

Question 19

Ruffini endings location, sensitivity, distribution?

Answer 19

Location: fibrous layer of jt capsule

Sensitivity: stretching of jt capsule; amplitudes and velocity of jt position

Distribution: greater density in proximal jts, particularly in capsular regions

Question 20

Golgi-Mazzini Corpuscles location, sensitivity, and distribution

Answer 20

Location: jt capsule

Sensitivity: compression of the jt capsule

Distribution: Knee jt. , jt capsule