APK2100C Exam 2

skeletal system

made of 3 organs- bones, cartilage and joints

bones provide framework while joints permit movement

types of cartilage

hyaline at ends of bones- reduce friction

elastic- external ear and eppiglotis

fibrocartilage- shock absorber in verterbral disc

cartilage basics

made of CT, 3 types, more extracellular matrix than cells ie more gelatinous ground substance

hyaline cartilage

chondrocytes in lacunae; amorphous texture/substance ie gel like; opaque like frosted glass

Is located on ends of long bonds: aritcular cartilage form join with structure; is growth plate within bones; costal cartilage ie ribs to sternum; respiratory structures and embyronic skeleton

elastic cartilage

lacunae within chondrocytes; not a frosted glass appearance and instead has abundance of elastic fibers,

located in epiglottis ie flap in throat that covers larynx AND outer ear ie pina

fibrocartilage

collagen fibers, located in pubic symphysis between hip joints AND menisci in knee joint/ interverterbal discs

perichondrium

peri= around, chon= cartilage ie tissue around cartilage, is dense irregular CT

bone function

support ie framework/scaffolding; protection; movement; mineral storage of calcium and phosphate; hemopoiesis ie formation of RBCs; energy storage and metabolism

classification of bone by shape

long vs short vs flat vs irregular

long bone

elongated shape ie humerus with 2 distinct ends; metacarpal/phalanges are these

short bone

cube like with not 2 distinct ends ie talus; has subclass of sesamoid which is sesame seed like ie patella; arrives from tendon to alter direction?

flat bone

flat and curved ie sternum ,rib, scapula

irregular bone

irregular shapes with protrusions/processes ie verterbrae

compact bone

outer layer that is hard

spongy bone

inside layer; open network,

anatomy of long bone

shaft in middle with 2 distinct ends; heads are covered by articular cartilage for reduced friction; compact bone lines outer layer ie superficial; spongy bone is open network area where we have red blood marrow; has periosteum and medullary cavity; blood vessels are within both spongy and compact bone for nutrient transports;

diaphysis

shaft of long bone

epiphysis

ends of long bone, can be distal or proximal based on attachment, can determine epiphysis or not by articular cartilage

metaphysis

junction at end of bone and shaft; has epiphyseal line that is calcified area of bone where growth plate used to be, an indicator of adult bone

periosteum

surrounds membrane around bone and functions in transport; arteries and veins pierce through this; perforating collagen fiber bundles attached to this and outer surface of bone called SHARPEYs

is ON external surface from shaft to epiphysis except where articular cartilage is; has superficial layer made of dense irregular CT and osteogenic layer the deeper layer made of osteoblasts and cytes

medullary cavity

open cavity with yellow bone marrow ie fats; tissue surrounding is compact bone

endosteum

inside of bone; thin osteogenic membrane with osteoblasts/cytes presentl located in central canal of osteons; covering spongy bone trabiculae ie medullary cavity, heads long bones inside the other 3 types of bones

Medullary

anatomy of short bone

no medullary cavity, both types of bone

osteoblasts/cytes

turn into calcified bone/produce bone cells

osteon

longitudinal opening hollow area; made of central canal ie Haersa; where blood vessel/ nerves from

trabiculae

littler pillars

anatomy of short/irregular/flat bones

NOT sandwich, top and bottom layers are continous like moonpie, periosteum superficial to compact bone, endosteum covering trabiculae

bone markings

purpose→ structure: projections are bumps like attachment site, reflects stress on bones ie 2 legs vs 4 legs; depression and opening present

microscopic anatomy of compact bone

superficial aspect of bone tissue, osteons presentl around central canal ie onion rings are concentric lamella which are calcified extracellular matrix part of ostens; cicrumfrential lamellae present which belong to ostens go around circumfreence of bone itself not just central canal; has endosteum, perforating canal which runs perpendicular to cenrtal canal and has perforating collagen fibers ie SHarpeys to attach periosteum to external surface of bone; lacunae present with osteocytes and canaliculi

canaliculi

lines in concentric lamellae; processes from osteocyte go throuhg this to reach other osteocytes for transport/connection

interstitial lamellae

calcified extracellular matrix not part of osteon but filling gaps between them

central canal of osteon

cavity within internal portion lined by endosteum

concentric lamellae

within we have lacunae which has osteocytes

collagen arrangement in lamellae

individual rings; in each concentric lamellae collagen fibers run in separate direction creating strength and resistance to twisting forces; WEIGHT BEARING columns; these are NOT sharpeys

microscopic anatomy of spongy bone

has network like webbing; trabeculae with red blood marrow found here

trabiculae

solid bone that forms network of cavities within cavities

4 situations of bone growth/development

formation of bone in embryo, growth of bone until adulthood, remodelling of bone throughout life, repair of fracture

ossification/genesis

process by which bones form in 4 situations

types of osteogenesis

intramembranous and endochondral

intramembranous ossification

bone derived from MESENCHYME, only skull and clavicles generated by this; start with mesenchyme to osteoblasts to bone and tubicule; calcified martix ….

endochondral ossification

formed with HYALINE cartilage, has epiffecial plate ie growth plate

bones getting longer

lengthening occurs on both side of growth plate; cartilage grows on head side while replacement of cartilage occurs on shaft side

at adulthood plates close and leave epiphseal line

bones getting wider

osteoblasts in periosteum add bone tissue to circumfrerential lamellae; osteoclasts remove bone from inner shaft wall at same rate hollowing out medullary cavity

bone resporption

taking away bone tissue via osteoclasts for remodelling ie putting in new while getting rid of old; use HCl and lysosome enzymes causing calcium release into blood and interstitial fluid which could be beneficial for endocrine system

osteoclast identification

have ruffled border to increase SA for HCL release and are multinucleate

bone deposition

opposite of resportion as we add to bone; ions must be present for osteoblasts to lay tissue such as calcium and phosphate, people deficient in this have frail bones; mineral salt crystals pack together to reduce risk of cracks

joint

ie articulation; bone on bone contact but also bone to other rigid elements; classified on structure/function

structural classification of joints

presence/absence of synovial cavity and types of CT

fibrous joint

no synovial cavity and has collagen fibers

synovial joint

synovial cavity and ligaments

cartilaginous joint

no synovial cavity and cartilage

functional classification of joints

on type/degree of movement;

synathreses= immovable

amphathroses= slightly movable

diarthroses= freely movable

fibrous joint

held by collagen fiber

suture

meeting point between cranial bones is dense fibrous CT; tightly held like jigsaw puzzle; very short fibers

syndesmosis

joint held by ligamanet ie fibula+tibula; interroseus membrane btwn raidus and and ulna; connects shafts; NOT radioulnar joint; normal size fibers

gomphosis

bone to another rigid element ie tooth, very short fibers

cartilaginous joints

associated with connecting ligamanets?

synchondrosis joint

hyaline cartilage ie growth plate and btwn rib and sternum; is immovable

symphyses joint

fibrocartilage found along midline of body ie trunk/pelvis, ie verterbral discs, good at absoring shock and in pubic symphysis

synovial joint

have LIGAMENTS binding bones together and enclosed synovial cavity which as fluid to reduce friction during movement; have large range of movement ie diarthrotic; make up majoritty of joints in body

types of synovial joints

planar, hinge, pivotal, condylar, saddle, ball and socket; describe mvoement or fit

components of synovial joint

bones connected by ligament of dense irregular CT proper; have cavity with lubricantl at ends of laong bones still have hyaline articular cartilage; articular capsule ie joint capsule creates space between bones with tough fibrous outer layer and synovial membrane as inner outer

synovial capsule

sleeve like enclosing cavity; fibrous outer layer is continous with periosteum and made of dense irregular CT to strengthen joint

The synovial membrane is the deeper, inner layers of cavity where there is NO hyaline, made of loose CT proper and responsible for secreting synovial fluid into cavity

synovium

ovum=egg; texture is egg white like; secreted from membrane and is filtrate of plasma but still has nutrients of blood; located in joint cavity and articular cartilage- cartilage is avascular and receives nutrients from this; acts like a sponge through weeping lubrication as joint moves it pushes against aritcular cartilage and squeezes synovium out and when decompressing it allows articular cartilage to puff up;

functions to reduce friction between bones and rough joint cartilage

cartilage associated with joints

articular- present on ends of long bones to reduce friction; HYALINE

articular disc- piece of cartilage acting as shock absorber and helps fit bones together at joints spanning the width of the cavity making it different from meniscus which requires 2 at the knee; is made of FIBROCARTILAGE

reinforcing ligaments of synovial joints

bands of collagen fibers= ligaments which strengthen joint

capsular= part of fibrous layer of capsule in thickened area ie glenohumeral; glenoid of fossa

extracapsular- outisde ligmanent of capsule ie medial and lateral collateral ligaments

intracapsular inside joints ie ACL/PCL

hip photo

acetabulum and head of femur; fovea= divot at head of femur, acetabular ligament part of acetabulum- ligament of head of femur is the LIGAMENTUM TERES- comes from fovea capitis to acetabulum

nerve and vascular supply of synovial joints

in joints tons of sensory nerves for pain and stretch info, functional redundancy of blood supply allows movement of joints because of multiple vessels

bursa

sacs with synovial fluid; reduce friction between body parts which rub against one another

tendon sheaths

sacs/sheets of synovial fluid like hot dog buns thats wrap around tendons found in small area on lots of structures to permit rubbing like wrist

movement permitted by synovial joints

gliding, angular, rotation (medial and lateral)

gliding

sliding flat surfaces of two bones across each other

flexion/extension

decreasing angle between two bones/increasing angle

abduction/adduction

moving limb away from midline/toward midline

circumduction

moving limb to create cone because roating only one side

roation

turning bone around longitudinal axis can medial or lateral

plane joint

gliding joint- articular surface of bones is flat/smooth located in intercarpal (Wrist) joints, between verterbral AND intertarsal ie angle joints

hinge joints

door hinge; one end is cylindrical and other is a trough allowing flexion/extension located in elbow, knee, and interphalangeal joints

hyperextension

flexion is decreasing angle and extension refers to going back to anatomical positioning; can hyperextend certain joints like the hip to increase the angle beyond anatomical position

can be bad when in knee

pivot joint

sleeve that surrounds axle allowing rotation at proximal radiulnar joints of attached axial joints

supination=palm up pronation= palm down, rotating at proximo radioulnar

condylar joint

both surfaces oval ; allows flexion/extension and adduction/abduction located in knuckle and wrist joints

saddle joint

1 concave and 1 convex surface ie horse saddle allowing adducition/abduction/flexion/extension located in thumb and sternoclavicular joint

opposition is movement of thumb toward hands ie holding a burger

ball and socket joint

1 surface is cup and other is sphere allowing flexion, extension, adduction, abduction, and rotation located in shoulder and hip joints

elevation/depression

lifting body part superior/inferior ie scapula or mandible

protaction/retraction

move forwards/back ie mandible

inversion/eversion

sole of foot medial/lateral

dorsification/plantar flexion

lifting foot to see superior surface/see point down ie ballet

sternoclavicular joint

made of 4 ligaments: interclavical, costoclavical, anterior and posteior sternoclavicular; very hard to dislocate this joint because made of so many ligaments ie easier to break collar bone;

can elevate, protract and opposite

glenohumeral joint

shoulder joint, glenoid fossa and humerus; on scapula, acromion, corecoid process; bands of ligamanets stablize; trade off with mvoement from ball socket joint

coracohumeral ligamentfrom coracoid process and humerus

joint capsule and 3 weak glenohumeral ligaments for strability

femorocoxal joint

hip joint with femur head oxocsa, ball and socket joint where acetabulum sits; acetabulum tuberosity is lip allowing for better fit of head of femur; have synovial cavity, articular capsule and ligamentum teres ie HEAD of femur that is intracapsular

capsular ligaments of hip

iliofemoral, ischiofemorum, and pubofemoral

knee joint

femorotibial joint, NO fiubula; largest most complext joint; primarily hingle joing with some roation, flexion and extensionl extremely strong and stable; shared joint space femoropatellar joint ie gliding joint

medial/lateral condyle of femur; covered in hyaline; aritculation only at femur and tibia

key components of knee joint

menisci, patella/patellar ligament, ACL, PCL, MCL, LCL

menisci

fibrocartilage discs that dont span width of joint ie knee has medial and lateral which act as shock absorber

patella/patellar ligament

down to tibia, attached to quadriceps

ACL

anterior cruciate ligament that intracapsular starting behind knee and through synovial; review this

PCL

posterior cruciate ligament; starts from behind and goes through synovial cavity to femur

MCL

tibial collateral ligament that is extracapsular from femur to tibia on medial side

LCL

fibular collateral ligament that is extracapsular on lateral side

muscle specific terminology

prefixes consisten, myo/mys=muscle