Ch. 8 Joints

Shoulder (Glenohumeral) Joint

-ball and socket -most freely moving joint but is one of the least stable

Cartilaginous joints

-bones united by cartilage, no joint cavity, not highly movable

pivot

uniaxial;rotation ulna to radius, proximal radioulnar, atlantoaxial, forearm, neck c1/c2

saddle

biaxial carpometacarpal, thumb

condylar

biaxial;flexion/extension; abduction/adduction metacarpophalangeal, wrist, knuckels, fingers, wrist

arthritis

->100 different types of inflammatory or degenerative diseases that damage joints -Most widespread crippling disease in the U.S. -Symptoms: pain, stiffness, and swelling of joint -Acute forms: caused by bacteria, treated with antibiotics -Chronic forms: osteoarthritis, rheumatoid arthritis, and gouty arthritis

developmental aspects of joints

-By embryonic week 8, synovial joints resemble adult joints -Joint's size, shape, and flexibility modified by use -Advancing years take toll on joints --Ligaments and tendons shorten and weaken --Intervertebral discs more likely to herniate --Most people in 70s have some degree of osteoarthritis

Lyme Disease

-Caused by bacteria transmitted by tick bites -Symptoms: skin rash, flu-like symptoms, and foggy thinking -May lead to joint pain and arthritis -Treatment --Long course of antibiotics

rheumatoid arhtritis

-Chronic, inflammatory, autoimmune disease of unknown cause --Immune system attacks own cells -Usually arises between ages 40 and 50, but may occur at any age; affects 3 times as many women as men -Signs and symptoms include joint pain and swelling (usually bilateral), anemia, osteoporosis, muscle weakness, and cardiovascular problems -RA begins with synovitis of the affected joint --Inflammatory blood cells migrate to joint, release inflammatory chemicals that destroy tissues --Synovial fluid accumulates joint swelling and inflamed synovial membrane which thickens pannus that clings to articular cartilage --Pannus erodes cartilage, scar tissue forms and connects articulating bone ends (ankylosis)

osteoarthritis

-Common, irreversible, degenerative (''wear-and-tear'') arthritis -May reflect excessive release of enzymes that break down articular cartilage -By age 85 half of Americans develop OA, more women than men -Probably related to normal aging process -More cartilage is destroyed than replaced in badly aligned or overworked joints -Exposed bone ends thicken, enlarge, form bone spurs, and restrict movement -Treatment: moderate activity, mild pain relievers, capsaicin creams

gouty arthritis

-Deposition of uric acid crystals in joints and soft tissues, followed by inflammation -More common in men -Typically affects joint at base of great toe -Treatment: drugs, plenty of water, avoidance of alcohol -If untreated joint ends fuse

treatment of RA

-Disrupt destruction of joints by immune system -Steroidal and nonsteroidal anti-inflammatory drugs decrease pain and inflammation -Immune suppressants slow autoimmune reaction -Some agents target tumor necrosis factor to block action of inflammatory chemicals -Can replace joint with prosthesis

Angular

-Increase or decrease angle between two bones -Movement along sagittal plane --Flexion ---Decrease the angle of the joint --Extension ---increase the angle of the joint ----Hyperextension -----Excession extension beyond normal range of motion -Movement along frontal plane --Abduction ---Movement away from the midline --Adduction ---Movement toward the midline -Circumduction --Involves flexion, abduction, extension, and adduction of limb ---"cone in space"

bursitis

-Inflammation of bursa, usually caused by blow or friction -Treated with rest and ice and, if severe, anti-inflammatory drugs

tendonitis

-Inflammation of tendon sheaths typically caused by overuse -Symptoms and treatment similar to bursitis

Gliding

-One flat bone surface glides or slips over another similar surface -Examples: --Intercarpal joints I--ntertarsal joints --Between articular processes of vertebrae

What movements are allowed for synovial joints?

-Origin --Attachment to immovable -Insertion --Attachment to movable

sprains and treatment

-Reinforcing ligaments stretched or torn -Partial tears slowly repair heal --Poor vascularization -Three options if torn completely --Time & immobilization --Ends sewn together --Replaced with grafts

3 stabilizing factors of synovial joints

-Shapes of articular surfaces (minor role) -Ligament number and location (limited role) -Muscle tendons that cross joint (most important)

What are sutures? Define the four types.

-Sutures are rigid interlocking joints that are immovable for protection of brain and they contain short connective tissue fibers. -coronal (frontal/parietal) -saggital(separate parietal) -squamous(parietal/temporal) -lambdoid(parietal/occipital)

rotation

-Turning of bone around its own long axis --Toward midline or away from it --Medial (toward) and lateral rotation (away) -Examples: --Between C1 and C2 vertebrae --Rotation of humerus and femur

Cartilage tears are treated by?

-arthroscopic surgery --ligament repaired, cartilage fragments, removed with minimal tissue damage or scarring -due to compresion and shear stress, fragments cause joint to lock or bind

hip (coxal) joint

-ball and socket -good range of motion but limited by deep socket

fibrous joints

-dense fibrous connective tissue no joint cavity -most synarthrotic ( depends on length of tissue fibers)

laters/medial tibiofemoral joints

-femoral condyles w/ lateral and medial menisci of tibia -allow flexion, extension and some rotation when the knee is partly flexed

Temporomandibular Joint (TMJ)

-hinge-dperession/elevation -gliding-(lateral excursion) side to side grinding of teeth -most easily dislocated joint

Synovial joints

-separated by fluid-filled joint cavity -diarthrotic -all limbs; most joints of body

What are the 6 distinguishing features of synovial joints and describe each

1. articular cartilage/hyaline cartilage-prevents crushing of bone ends 2. joints (synovial) cavity-small-fluid filled potential space 3. articular joint capsule-external(fibrous layer)-dense irregular connective and inner (synovial membrane)-loose connective and makes synovial fluid 4. synovial fluid-viscous slippery filtrate of plasma and hyaluronic acid, lubricates & nourishes articular cartilage, contains phagocytic cells 5. reinforcing ligaments- A. capsular-thickened part of fibrous layer; B. extracapsular-outside capsule; C. intracapsular-deep to capsule, covered by synovial membrane 6. nerves & blood vessels-nerve fibers detect pain, monitor joint position and stretch, capillary bends supply filtrate for synovial fluid

Bursae & tendon sheaths

1. bursae- sacs lined with synovial membrane that contain synovial fluid and reduce friction 2. tendon sheaths- elongated bursae wrapped completely around tendon subjected to friction

dislocations (luxations) vs subluxation

1. luxation- bones forces out of alignment, serious falls or contact sports 2. subluxation- partial dislocation

Define the following special movements of synovial joints: supination/pronation, dorsiflexion/plantar flexion, inversion/eversion, protraction/retraction, elevation/depression, opposition

1. supination-radius & ulna paralell; palm down to palm up 2. pronation-radius rotates over ulna; palm up to palm down 3. dorsiflexion-point toes up 4. plantar flexion-point toes down 5.inversion-point foot tworad midline (medial) 6.eversion-point foot away form midling (lateral) 7.protraction-bottom jaw out (anterior) 8.retraction-bottom jaw in (posterior) 9.elevation-close mouth;decreasing angle 10.depression-open mouth;increasing angle 11. opposition-touching tumb to finger tip

What are the 3 types of fibrous joints.

1. sutures 2. syndesmoses-connected by ligaments; fibrous tissue can vary in length 3. gomphoses- (peg-in-sockets) of teeth in alveolar sockets; periodontal ligament holds tooth in socket

what are the 2 types of cartilaginous joints?

1. synchondroses-bones united by hyaline cartilage i.e. temporary epiphyseal plate joints, cartilage of 1st rib w/ manubrium; all synarthrotic 2. symphyses- bones united by fibrocartilage i.e. strong, flexible aphiarthroses

Additional features of synovial joints

1.fatty pads-cushioning b/w fibrous layer & synovial membrane or bone 2. articular discs (menisci)-fibrocartilage spearates articular surfaces to improve fit of bone ends, stabilize joint, and reduce wear and tear.

what are the 3 general types of movements at synovial joints?

1.gliding-nonaxial;carpals, tarsals, vertebrae 2. angular-flexion,extension,hyperextension,abduction,adduction,circumduction 3.rotation-medial/lateral rotation

What are the 4 ranges of motion for synovial joints?

1.nonaxial-slipping 2.uniaxial-one plane 3.biaxial-2 planes 4.multiaxial-3 planes

What are the 3 functional classifications of joints?

1.synarthroses-immovable 2. amphiarthroses-slightly movable 3. diarthroses- freely movable

hinge

elbow, interphalangeal, humerus to ulna uniaxial;flexion/extension

What are the 3 structural classifications of joints?

fibrous cartilaginous synovial

What is the larges,t most complex joint of the body?

knee joint which is composed of 3 joints surrounded by a single joint cavity

ball-and-socket

multiaxial shoulder, hip

plane

nonaxial;gliding intercarpal, intertarsal, vertebral articular surfaces, wrists, feet,

femoropatellar joint

plane allows gliding motion during knee flexion

What are the six types of synovial joints?

plane hinge pivot condylar saddle ball-and-socket

articulation

site where 2 or more bones meet

functions of joints

skeleton mobility hold skeleton together