joints

Question 1

what are Joints/Articulations

Answer 1

Point of contact between bones, cartilage and bone, teeth and bones.

Question 2

how can joints/articulations be classified

Answer 2

Classified structurally by anatomy

Classified functionally by motion – immovable, slightly immovable or freely movable.

Question 3

what are joints supported by and why might greater support be needed

Answer 3

Supported by ligaments, joint capsules and surrounding muscles.
(greater support is required for those joints are more moveable)

Question 4

structural classification is based on what

Answer 4

on material between bones and whether there is a synovial cavity

Question 5

name and explain the 3 structural classifications of joints

Answer 5

Fibrous joints
- no cavity just fibrous connective tissue which is very collagen-rich

Cartilaginous joints
- bones held together by cartilage

Synovial joints
- have synovial cavity and dense irregular tissue of articular capsule and often ligaments (An articular capsule is an envelope surrounding a synovial joint, the knee is an ex of a joint with articular capsule surrounding it)

Question 6

what is synovial fluid for

Answer 6

helps lubricate the surfaces within a moveable joint

Question 7

name and explain the 3 functional classifications of joints

Answer 7

Synarthroses
– immoveable joints
- pelvis , sutures of skull, teeth sockets

Amphiarthroses
- slight movement in joints
- Epiphysis, tibia-fibula membrane sheath, vertebrae and pelvic symphysis

Diarthroses
- free movement = all are synovial joints (ball and socket and hinge type joints)

Question 8

name 3 fibrous joints

Answer 8

suture
syndesmosis
gomphosis

Question 9

explain the fibrous joint suture

Answer 9

e.g. skull = ex of synarthrosis-immovable

joined by thin layer of dense fibrous connective tissue, that will not separate once joined during early childhood

Question 10

explain the fibrous joint syndesmosis

Answer 10

e.g. tibia & fibula =ex of amphiarthrosis – slight movement

Due to Greater distance between tibia and fibula, and amount of dense fibrous material (sheath between them). Slight movement is important for stabilization and preventing tearing from stress

Question 11

explain the fibrous joint gomphosis

Answer 11

e.g. tooth root in socket = ex of synarthrosis - immovable

Gomphosis binds the teeth to the bony socket known as alveolar

Question 12

describe the movement of fibrous joints

Answer 12

little or no movement

Question 13

describe the movement of cartilaginous joints

Answer 13

little or no movement

Question 14

name 2 cartilaginous joints

Answer 14

synchondrosis
symphysis

Question 15

explain the cartilaginous joint synchondrosis

Answer 15

hyaline (non fibrous cartilage) cartilage

e.g. epiphyseal plate = ex of synarthrosis (immovable)

Question 16

explain the cartilaginous joint symphysis

Answer 16

fibrocartilage (tough fibrous cartilage)

e.g. pubic symphysis and intervertebral joints = these are amphiarthrosis (slightly movable)

Question 17

explain what synovial joints are

Answer 17

Formed of a Synovial cavity

Will require Articular cartilage

Theres also an Articular capsule -
- Inner layer = synovial secretory membrane

Synovial fluid – viscous fluid found in cavities of synovial joints, to reduce friction between articular cartilage of synovial joints during movement

Ligaments

Some contain menisci

Question 18

name some common disorders of joints

Answer 18

rheumatism
arthritis
sprain
strain

Question 19

explain rheumatism

Answer 19

refers to any painful state of supporting structures of the body such as bones, ligaments, tendons, joints, and muscles.

Question 20

explain arthritis

Answer 20

refers to several disorders characterized by inflammation of joints accompanied by stiffness.

Question 21

name and explain 3 types of arthritis

Answer 21

Rheumatoid arthritis (RA)
is an autoimmune disease and is characterized by an inflammation of the synovial membranes. Can affect all ages and all joints in body

Osteoarthritis
is a degenerative joint disease characterized by deterioration of the articular cartilage. It is non-inflammatory and generally affects the weight-bearing joints. This is Common in older ages (elderly)

Gouty arthritis
is a condition in which sodium ureate crystals are deposited in the soft tissues of joints, causing inflammation, swelling, and pain. This arthritis is associated with diet and lifestyle

Question 22

explain a sprain

Answer 22

is a forcible wrenching or twisting of a joint that stretches or tears its ligaments without dislocation.

Question 23

explain a strain

Answer 23

a stretched or partially torn muscle.

Question 24

explain the effects of aging on joints

Answer 24

Slowing of synovial fluid production, so less lubrication and protection of joints

Thinning of articular cartilage, causing spine compression and so pain

Ligaments shorten and lose flexibility

All of these can be Influenced by genetic factors

All of the above result in reduced mobility