Joints

Question 1

Define joint, what are two types

Answer 1

two skeletal elements come together; synovial and solid

Question 2

Synovial Joint

Answer 2

skeletal elements are separated by a narrow articular cavity (cavity looks larger because cartilage doesn’t attenuate X-rays as well as bone)

Question 3

What are the three features of a synovial joint?

Answer 3

1) hyaline cartilage
2) inner synovial membrane
3) outer fibrous membrane

Question 4

Outer fibrous membrane

Answer 4

dense connective tissue that surrounds and stabilizes the joint; can thicken to form ligaments

Question 5

Inner Synovial Membrane

Answer 5

encloses the joint cavity at the margins of the joint surfaces at the interface b/w cartilage and bone; very vascular and produces synovial fluid which is a lubricant for the joint

Question 6

Hyaline Cartilage

Answer 6

covers articulating surfaces of skeletal elements

Question 7

What are synovial bursae?

Answer 7

closed sac of synovial membrane that occur b/w structures to reduce friction

Question 8

Where do we find synovial bursae?

Answer 8

tendon/bone; tendon/joint; skin/bone

Question 9

What is a tendon sheath?

Answer 9

a closed sac of synovial membrane that covers a tendon to reduce friction

Question 10

We classify joints by ______ and _______.

Answer 10

Shape; movement

Question 11

What are the seven shapes of synovial joints?

Answer 11

1. plane (flat)
2. hinge
3. pivot
4. bicondylar
5. condylar (ellipsoid)
6. saddle
7. ball and socket

Question 12

What are the three types of movement of synovial joints?

Answer 12

1. uniaxial (UA) - moves in one direction (x, y, or z)
2. biaxial (BA) - moves in two directions (xy, yz, or xz)
3. multiaxial (MA) - moves in all directions

Question 13

Describe and provide an example of a plane joint.

Answer 13

UA - sliding/gliding when a bone moves across another

i.e. acromioclavicular joint (scapula glides past clavicle when raising and rotating arm)

Question 14

Describe and provide an example of a hinge joint.

Answer 14

UA - allows movement along 1 axis and the direction is transverse
i.e. humero-ulnar (elbow) joint (allows for flexion and extension)

Question 15

Describe and provide an example of a pivot joint.

Answer 15

UA - allows movement along axis that is longitudinal to the shaft of the bone
i.e. atlanto-axial joint. (in neck, allows you to turn head left and right)

Question 16

Describe and provide an example of a bicondylar joint.

Answer 16

BA - allows complete movement in 1 axis and limited movement in 2nd axis; formed by two convex condyles that articulate w/ concave or flat surfaces
i.e. knee joint

Question 17

Describe and provide an example of a condylar (ellipsoid) joint.

Answer 17

BA - movement around 2 axes that are at right angles to each other
i.e. wrist joint (flexion, extension, abduction, adduction, limited circumduction)

Question 18

Describe and provide an example of a saddle joint.

Answer 18

BA - movement around 2 axes that are at right angles to each other, articular surface looks like a saddle
i.e. Carpometacarpal (thumb) joint (flexion, extension, abduction, adduction, circumduction)

Question 19

Describe and provide an example of a ball and socket joint.

Answer 19

MA - movement in all directions

i.e. hip joint (flexion, extension, abduction, adduction, circumduction, rotation)

Question 20

What are three common additional features of synovial joints that are not universal to all synovial joints.

Answer 20

1. Articular Discs (Fibrocartilage)
2. Fat Pads
3. Tendons

Question 21

Articular Discs

Answer 21

(fibrocartilage) absorb compression forces, adjust to changes in contours of joint surfaces during movement, and increase range of motion

Question 22

Fat Pads

Answer 22

can be found between inner synovial and outer fibrous membranes; moves into and out of region as joint contours change

Question 23

Solid Joints

Answer 23

adjacent skeletal elements inked by fibrous connective tissue or cartilage

Question 24

Three types of fibrous connective tissue linked solid joints?

Answer 24

1. suture
2. gomphoses
3. syndesmoses

Question 25

Suture (solid) joints

Answer 25

skull only, sutural ligament connects bone plates

Question 26

Gomphoses (solid) joints

Answer 26

b/w teeth and adjacent bone

Question 27

Syndesmoses (solid) joints

Answer 27

two adjacent bones linked by a ligament

Question 28

List two examples of syndesmoses joints.

Answer 28

Ligamentum Flavum (connects vertebral laminae) and Interosseus membrane (connects radius and ulna)

Question 29

What are the two types of cartilaginous solid joints?

Answer 29

Synchondroses and Symphyses

Question 30

Synchondroses (solid) joints

Answer 30

two ossification centers in a developing bone remain separated by cartilage (growth plate)

Question 31

Symphyses (solid) joints

Answer 31

two separate bones connected by cartilage, typically occurring in midline (i.e. intervertebral discs and pubic symphysis)

Question 32

Osteoarthritis (ITC)

Answer 32

degenerative joint disease related to aging that accounts for 1/4 PCP visits; can be secondary to RA or infection; treat with weight loss, exercise, anti-inflammatory medication, or joint replacement

Question 33

Biological "flow chart" of osteoarthritis progression (ITC)

Answer 33

decreases in water and proteoglycan in cartilage leads to increased fragility and susceptibility to mechanical disruption of the joint - ultimately cartilage wears down causing bone fissures and thickening synovial fluid can enter these fissures creating large cysts and osteophytes (bony outgrowths) form result: altered biomechanics forces -- stress -- disruption of joint

Question 34

Arthoscopy (ITC)

Answer 34

surgical procedure in which a small telescope is inserted through a small incision to visualize a joint; other tools may be inserted through separate incisions to repair any damage; common in hip, shoulder, knee, ankle

Question 35

Benefits of arthoscopy (ITC)

Answer 35

quick recovery time, local anesthetic or light anesthesia

Question 36

Joint Replacement

Answer 36

surgical procedure where both sides of the joint are replaced to improve quality of life (joint destruction or degenerative joint disease is reducing QOL) typically done for larger joints, but with tech advancements smaller joint replacements are becoming increasingly common