Chapter 9 Joints Flashcards
*Joint (Articulation or Arthrosis)
point of contact
- between 2 bones
- between bones and cartilage
- between bones and teeth
Arthrology
study of joints
Kinesiology
study of motion of the human body
*How are joints classified?
Structural
- Is there a joint cavity?
- What type of connective tissue is involved?
Functional
-What degree of movement is produced?
*Types of Structural Classification of Joints
Fibrous joints
Cartilaginous Joints
Synovial joints
*Types of Functional Classification of Joints
Synarthrosis
Amphiarthrosis
Diarthrosis
Fibrous joint
no synovial cavity
bones are held together by dense irregular connective tissue rich in collagen fibers
permit little to no movement
Cartilaginous joint
- no synovial cavity
- bones are held together by cartilage
- little to no movement (synarthrosis)
- articulating bones held together by hyaline or fibrous cartilage
Synovial joint
bones forming these joints have a synovial cavity
united by dense irregular connective tissue of an articular capsule and often by accessory ligaments
freely moveable
Synarthrosis
immoveable joint
Amphiarthrosis
slightly moveable joint
Diarthrosis
freely moveable joint
all are synovial joints
variety of shapes which permit several different movements
3 types of Fibrous Joints
sutures
syndesmoses
interosseous membrane (type of syndesmoses)
Suture (Fibrous Joint)
thin layer of dense irregular connective tissue
only between bones of the skull
What are the functions of a suture?
interlocking edges add strength
decrease chance of fracturing
immoveable (synarthrosis) or slightly moveable (amphiarthrosis)
shock absorption of the skull
Synostosis
complete fusion of two separate bones into one
immoveable (synarthrosis)
Syndesmosis (syndesmoses) Fibrous Joint
- arranged in a bundle (band or ligament) which permits limited movement
- greater distance between articulating surfaces
- more dense irregular connective tissue than suture (interosseous membrane)
Syndesmosis (syndesmoses) examples
tibiofibular ligament dentoalveolar joint (gomphosis) interosseous membrane
Gomphosis (Fibrous Joint) Syndesmosis Type
articulation between roots of teeth
type of syndesmosis
cone shaped peg fits into socket
Interosseous Membrane (Fibrous Joint)
- Broad sheet of dense irregular connective tissue
- binds neighboring long bones
- important role in defining range of motion between them
- permits slight movement (amphiarthrosis)
- increased attachment surface for muscles (which produce movement of feet and digits
Interosseous Membrane Examples (syndesmoses)
Between radius and ulna
Between Tibia and Fibula
What 2 types of cartilage hold together cartilaginous joints?
hyaline or fibrous
2 types of cartilaginous joints
synchondroses (epiphyseal cartilage is this type)
symphysis
Synchondrosis (synchondroses) (Cartilaginous)
- connecting material is hyaline
- Slightly moveable (amphiarthrosis) to immoveable (synarthrosis)
Synchondrosis (synchondroses) example
joint between first rib and manubrium
Symphysis (Cartilaginous)
ends of articulating bones are covered with hyaline cartilage but a broad, flat disc of fibrouscartilage connects to bones
- all are midline in the body
- slightly moveable (amphiarthrosis)
Symphysis Example
pubic symphysis
junction of manubrium and body of sternum
intervertebral discs
Epiphyseal cartilage (Synchondroses)
hyaline cartilage growth centers during endochondrial bone formation *NOT JOINTS ASSOCIATED WITH MOVEMENT immoveable joint (synarthrosis)
Epiphyseal cartilage Example
epiphyseal growth plate
*When bone elongation ceases what happens?
bone replaces hyaline cartilage and becomes synostosis (bony joint)
What is synostosis?
bony joint
What characteristics distinguish synovial joints from others?
- presence of space (synovial/joint cavity) between articulating bones
- synovial cavity allows considerate movement
- all are functionally freely moveable (diarthrosis)
What is the space in a synovial joint called?
synovial or joint cavity
What are the bones at a synovial joint covered in?
hyaline cartilage (articular cartilage)
*Articular cartilage
cartilage that covers the articulating surfaces of bones
smooth, slippery surface but does not bind bones together
*What does articular cartilage do?
reduces friction between bones in joints during movement and helps absorb shock
Articular capsule is also known as
joint capsule
*3 Articular capsule functions
surrounds a synovial joint
encloses the synovial cavity
unites articulating bones
What is the articular capsule layers composed of?
outer fibrous membrane
inner synovial membrane
What is the fibrous membrane of the articular capsule composed of?
Dense irregular connective tissue (usually collagen fibers)
What is the fibrous membrane of the articular capsule attach to?
periosteum of articulating bones
*What is the fibrous membrane of the articular capsule a continuation of?
thickened continuation of the periosteum between bones
*What is the functions of the fibrous membrane of the articular capsule?
flexibility permits considerable movement at a joint
while its great tensile strength (resistance to stretching) helps prevent the bones from dislocating or displacement of bones from a joint
How are the fibers of some fibrous membranes arranged and what is the purpose?
parallel bundles of dense connective irregular connective tissue that are highly adapted to resisting strains
Ligaments
fibrous membrane bundles that hold bones close together in a synovial joint
Synovial membrane
inner layer of the articular capsule
areolar connective tissue with elastic fibers
At many synovial joints the synovial membrane will include
accumulations of adipose tissue
What are the accumulations of adipose tissue of the synovial membrane called?
articular fat pads
Articular fat pad Example
infrapatellar fat pad of the knee
Double jointed
not really extra joints but greater flexibility in their articular capsules and ligaments
What can happen with double joints?
less structurally stable
more easily dislocated
Synovial Fluid
viscous, clear or pale yellow fluid (like egg white)
What is synovial fluid and where is it located?
forms a thin layer over surfaces within the articular capsule
synovial cavity
Functions of synovial fluid
reduce friction by lubricating the joint
absorbs shock
supply oxygen and nutrients, remove carbon dioxide and metabolic waste from chondrocytes within articular cartilage
What happens to synovial fluid when a joint is immobile for awhile
it becomes viscous or gel like
Why is warming up before exercise beneficial in relation to synovial fluid of the joints?
movement increases it becomes less viscous
stimulates production and secretion of synovial fluid
2 types of Accessory ligaments
extracapsular ligaments
intracapsular ligaments
Accessory ligaments location
synovial joints
Extracapsular ligament
lie outside the articular capsule
extracapsular ligament example
fibular and tibial collateral ligaments of the knee joint
Intracapsular ligament
lie within the articular capsule but are excluded from the synovial cavity by folds in the synovial membrane
Intracapsular ligament Example
anterior and posterior cruciate ligaments ACL LCL PCL MCL
Articular discs are also called
menisci
Articular discs
bind strongly to the inside of the fibrous membrane, usually subdivide the synovial cavity into 2 spaces allowing separate movements to occur in each space
*Functions of Articular Discs (Menisci)
- shock absorption
- better fit between articulating bony surfaces
- providing adaptable surfaces for combined movements
- weight distribution over a greater contact surface
- distribution of synovial lubricant across the articular surfaces of a joint
Labrum
fibrocartilaginous lip that extends from the edge of a joint socket
Where is labrum most prominent?
ball and socket joint of the shoulder and hip
Nerves that supple a joint are the same as those that supply ___
Skeletal muscles that move the joint
Nerve endings convey ____ from the joint to the spinal cord and brain for processing
pain
Other nerve endings respond to the _____ __ _____ and ____ at a joint such as when a physician strikes the tendon below your knee cap to test for reflexes
degree of movement
stretch
Veins remove ____ and ____ from the joints
carbon dioxide
wastes
Chondrocytes in the articular cartilage of a synovial joint receive ____ and ___ from synovial fluid derived from blood while all other joint tissues are supplied directly by _______
oxygen
nutrients
capillaries
Bursae
-saclike structures filled with synovial fluid that cushion movement of one body part over another
Bursae Example locations
knee and shoulder
How are bursae similar to joint capsules?
- walls consist of outer fibrous membrane of dense connective tissue lined by a synovial membrane
- filled with small amounts of fluid
*Where are bursae located and what is their function?
- between skin and bones
- tendons and bones
- ligaments and bones
- cushion the movement of these body parts against each other
Bursitis
Acute or chronic inflammation of the bursae
Bursitis causes
- irritation from repeated, excessive exertion of a joint
- trauma
- acute or chronic infection
- RA
Bursitis Symptoms
Pain
Swelling
tenderness
limited movement
Bursitis Treatment
anti-inflammatory meds
injections
cortisol-like steroids
Tendon sheaths
aka synovial sheaths
tube like bursae
wrap around tendons subject to a great deal of friction
What are the 2 layers of tendon sheaths?
visceral layer
outer layer
*Visceral tendon sheath layer attach to
the surface of tendons
*Outer tendon sheath layer attach to
parietal layer attaches to bone
What does the tendon sheath protect?
all sides of a tendon from friction as it slides back and forth
Where are tendon sheaths found?
where tendons pass through synovial cavities
Tendon sheath location example
tendon of bicep brachii muscle at the shoulder joint
Where are other locations or tendon sheaths?
wrist and ankle (where tendons come together in a confined space
fingers and toes (where there is great deal of movement)
Four main categories of synovial movements
gliding
angular
rotation
special movements
Gliding movements
flat bone surfaces glide back and forth and side to side
limited in range
little change in angle between bones
Gliding Examples
intercarpal and intertarsal joints
Angular movements
increase or decrease in the angle between articulating bones
Types of Angular movements
flexion
extension
lateral flexion
hyperextension
Flexion
decrease in the angle of articulating bone (usually along sagittal plane)
Extension
increase in the angle of articulating bones (usually along sagittal plane)
Lateral flexion
involves movement of trunk along frontal plane
Hyperextension
continuation of extension beyond anatomical position
Abduction
radial deviation
movement of a bone away from the midline
Adduction
ulnar deviation
movement of a bone toward the midline
Circumduction
movement of a distal end of a body part in a circle
Rotation
bone revolves around own longitudinal axis
Special movement Types
elevation depression protraction retraction inversion eversion dorsi flexion plantar flexion supination pronation opposition
Elevation
superior movement of body part
Depression
Inferior movement of body part
Protraction
Anterior movement of body part in transverse plane
Retraction
Posterior movement of body part in transverse plane
Inversion
medial movement of sole
Eversion
lateral movement of sole
Dorsiflexion
bending foot in direction of dorsum (superior surface
Plantar flexion
bending foot in direction of plantar surface
Supination
movement of forearm turning palm anteriorly
Pronation
movement of palm turning palm posteriorly
Opposition
movement of thumb across palm to touch fingertips on same hand
Types of Synovial Joints
Plane joints Hinge Joints Pivot Joints Condyloid Joints Saddle Joints Ball and Socket Joints
Plane Joints (Synovial)
articulated surfaces flat or slightly curved
Plane Joints Functions (Synovial)
many biaxial diarthroses (freely moveable)
back and fourth, side to side
Some triaxial diarthroses
back and forth, side to side, rotation
Plane Joints Locations (Synovial)
intercarpal
intertarsal
sternocostal
vertebrocostal joints
Hinge Joints (Synovial)
convex surface fits into concave surface
Hinge Joints Functions (Synovial)
Uniaxial diarthrosis
flexion and extension
Hinge Joints Locations (Synovial)
Knee
Elbow
Ankle
Interphalangeal joints
Pivot Joints (Synovial)
rounded or pointed surface fits into ring formed partly by bone and partly by ligament
Pivot Joints Functions (Synovial)
Uniaxial diarthrosis
rotation
Pivot Joints Locations (Synovial)
Atlanto-axial
Radioulnar joints
Condyloid Joints (Synovial)
oval-shaped projection fits into oval-shaped depression
Condyloid Joints Functions (Synovial)
Biaxial diarthrosis
flexion-extension
abduction-adduction
Condyloid Joints Locations (Synovial)
Radiocarpal and metacarpophalangeal joints
Saddle Joints (Synovial)
articular surface of one bone is saddle-shaped articular surface of other bone is sits in saddle
Saddle Joints Functions (Synovial)
Biaxial diarthrosis
flexion-extension
abduction-adduction
Saddle Joints Locations (Synovial)
carpometacarpal joint between trapezium and metacarpal of thumb
Ball & Socket (Synovial)
Ball like surface fits into cuplike depression
Ball & Socket Functions (Synovial)
Triaxial diarthrosis
flexion-extension
abduction-adduction
rotation
Ball & Socket Locations (Synovial)
Shoulder and hip joints
Synovial Joint Examples
Hip, Knee, Shoulder and Elbow
*What are the 6 Factors that affect contact and range of motion at synovial joints?
Structure and shape of articulating bones strength and tautness of joint ligaments arrangement and tension of the muscles contact of soft parts hormones disuse