Joints- WK2 ( Ch 2 )

Question 1

Differentiate between the simple synovial joint categories.

Answer 1

Ovoid: has a paired mating surface that is imperfectly spherical , adjacent parts have a changing surface curvature, articular surface is convex and the other is concave

Saddle: paired convex and concave surfaces; oriented at 90 degrees to eachother

Question 2

List the 7 elements associated with synovial joints

Answer 2

1) Articular Cartilage
2) Articular/Joint Capsule
3) Synovial Membrane
4) Synovial Fluid
5) Ligaments
6) Small Blood Vessels
7) Sensory Nerves

Question 3

What is the importance of water to ground substance ?

Answer 3

peri-articular tissue; capsule, ligaments, tendons, cartilage, and fibrocartilage are all made of collagen, cells, and ground substance

water provides a fluid medium for diffusion of nutrients within ground substance matrix

proteglycans in tissue tend to swell due to water retention and thus become turgid like a balloon.

Question 4

For the following connective tissue describe: category, composition, healing potential, sensation, function:

Ligament

Answer 4

• A dense regular connective tissue; composed of high type 1 collagen, low elastin, few fibroblasts, low proteoglycan content
• connect bone to bone, protect against excessive movement

Question 5

For the following connective tissue describe: category, composition, healing potential, sensation, function:

Tendon

Answer 5

• Dense regular connective tissue; composed of high type 1 collagen, low elastin content, few fibroblasts, low proteoglycan content
• transmit forces from muscle to bone

Question 6

For the following connective tissue describe: category, composition, healing potential, sensation, function:

Joint Capsule

Answer 6

• dense irregular connective tissue; mostly type I collagen
• enclose synovial joints
• limited healing potential

Question 7

For the following connective tissue describe: category, composition, healing potential, sensation, function:

Articular Cartilage

Answer 7

• hyaline; type II collagen fibers, high proteglycan content
• avascular and aneural
• reduces joint friction

Question 8

For the following connective tissue describe: category, composition, healing potential, sensation, function:

Fibrocartilage

Answer 8

• mixture of dense connective and articular cartilage; type II collagen fibers, high proteoglycan content
• shock absorption and tensile strength
• guide arthrokinematics
• aneural, limited blood supply
• peripheries may heal

Question 9

For the following connective tissue describe: category, composition, healing potential, sensation, function:

Bone

Answer 9

• Falls under bone; made of spongy and compact bone
• innervated and vascular supply
• heals well

Question 10

How does articular get nutrition ? and how can therapists promote that process ?

Answer 10

• Nourished by synovial fluid facilitated by milking action of articular surface deformation during joint loading
• by encouraging exercise !

Question 11

Explain Wolff’s Law. How can it be pathological for bone and other connective tissue ?

Answer 11

• bone is laid down in areas of high stress and reabsorbed in areas of low stress.
• if too much is laid down spurs may form ( osteophytes ), due to pulls from connective tissue or muscle
• pores may also from lack of stressors

Question 12

How long does it take for the following tissues to heal ? bone, ligament/tendon/joint capsule, articular cartilage

Answer 12

Bone: 6-8 weeks
Ligament/Tendon/Joint Capsule: 3-6 weeks
Articular Cartilage: repaired poorly or not at all

Question 13

What is the difference between acute trauma and chronic trauma ?

Answer 13

acute: single overwhelming event that produces detectable pathology
chronic: accumulation of lesser injuries over extended period.

Question 14

What is the difference between a dislocation and a subluxation ?

Answer 14

Dislocation: complete dissociation
Subluxation: partial dissocation

Question 15

Regarding the phases of healing, how long does each phase last and what happens during each phase ?

Answer 15

Inflammation: <1 week, inflammatory cells and leukocytes crowd area; increased vascular permeability

Repair: about 3 weeks; cell proliferation; fibers re-aligned, new tissue strength is 15% of the original strength; gentle tension should be applied to encourage proper collagen orientation

Remodeling: 3wks to 6mo; Scar tissue should be stressed to improve tissue quality

Question 16

What happens if a therapist is too aggressive during the repair phase of healing ?

Answer 16

delayed or suppressed healing; could cause reinjury

Question 17

What happens if the remodeling process is not carried out properly ?

Answer 17

Low quality scars; patient may be continuously bothered by pain despite repair

Question 18

How does immobilization or disuse affect the following tissues: Ligament, Tendon, Joint Capsule, Articular Cartilage, Bone.

Answer 18

Ligament: decreased tensile strength, decreased collagen and cross linking

Tendon: muscle weakness and atrophy; loss of interdigitation

Joint Capsule: capsule contracture, adhesion in synovial folds

Articular Cartilage: loss of mass, volume, and strength

Bone: loss of mass, volume, and strength

Question 19

How are the effects of ageing similar to the effects of immobilization or disuse on connective tissues ?

Answer 19

• decreased repair capacity
• decrease tissue strength
• decreased GAG molecules
• tendons become less stiff

Question 20

What type of exercise is appropriate for rehab of the following connective tissues ?

Ligament, Tendon, Cartilage, Bone

Answer 20

Ligament: tensile loads; recovery can take months
Tendon: tensile loads
Cartilage: low frequency compressive loads
Bone: High frequency loads

Question 21

Explain the cycle of joint dysfunction as if you were telling a patient.

Answer 21

1. joint cannot move thus muscle that moves it cannot move
2. muscles cannot be restored to normal if the joints are not free to move
3. normal muscle function depends on normal joint movement
4. impaired muscle function may deteriorate joints

Question 22

Review the classification of connective tissue types.

Answer 22

…

Question 23

What is the name of the cell that synthesizes collagen ?

Answer 23

Fibroblast

Question 24

What is the name of the cell that synthesizes cartilage ?

Answer 24

Chondroblast