Skeletal System
Period: 5
Emory Celestino
Anatomy of the long bone
Types of bones
Names of all the bones
Bone remodeling
Bone fracture repair
Joints
Movements allowed by Synovial Joints
Differences between male and female skeleton
Disorders/diseases
Limbs(Appendicular)
Axial
The Skull and Sutures
Starting from the Anterior side:
Most Superior to most Inferior :
Frontal (aka forehead): Makes up the front side of the head
Nasal (aka nose bridge) : Makes up the "bridge" of the nose
Zygomatic (aka the cheek bone): Makes up the cheekbone
Maxillary ( aka the upper mouth): Makes up the upper mouth and is connected to the nasal and zygomatic
Mandible (aka jawline): Disconnected part of the skull
Suture: Coronal
Top view:
Partial: two bones fused together by sutures
Suture: Saggitial
Posterior:
Optical: Back of the head
Suture: Labium
Side view:
Temple: The area above cheek bone.
Suture: Squamous
Legs (Proximal to Distal)
Femur: Connected to the pelvic
Tibia: Tibia is more medial than its pair
Fabia: Fabia is more lateral than the tibia (it's pair)
Talus: Sits right above the tarsals
Tarsals: Seems like little rocks
Calcaneus: The heel
Metatarsals: not the toes, more like the entry way to the toes
Phalanges: the toes
Arms (Proximal to Distal)
Humorous: Connected toe scapula
Radius: More Medial to its pair
Ulna: More lateral to its pair (the radius)
Carpals: the wrist
Metacarpals: the palm
Phalanges: Fingers
Sternum:
Superior:
Manubrial , the flat bone closes to the clavicle
Body: longest bone of the sternum
Xiphoid process: the pointy part of the sternum
Costal Hyline Cartilage is what branches and supports the ribs
Shoulders
Clavicle: the collar bone
Scapula: The shoulder blade
Ribs:
1-7 are true ribs
8-12 are false ribs
Sacrum (medial to lateral) to the pelvic
Medial Sacrum Crest: Fused vertebrae
Coccyx: Tail bone
Illum: the widest part of the pelvic
Pelvic bone: the media at times can it the " virginal bone"
Pelvic arch + Pubic Symphysis
Spine:
Superior to Inferior
Cervical: closes to head
Atlas: has a long piece to it
Axis: has no long piece, but the opening is wider
Thoracic: Starts when vertebras increase in size
Lumbar: The widest type of vertebras and its fussed to the sacrum
Female pelvic:
Male Pelvic tend to have a wider hip frame
Ischial Spine and Pelvic inlet tend to be more of a circle shape
Pubic Arch is a wider at the entry way for the pubic arch
Male pelvic:
Male Pelvic tends to have a narrower hip frame.
Ischial spine and Pelvic inlet tend to a more oval shape rather than a circle
Pubic Arch is narrower and cramped
The basic structure
- As explored before, the closer the bone is to the area of connection the more proximal it is, however the polar opposite of this is distal.
- Applying this to the structure of the long bone, the ends of the bone is either called proximal epiphyseal or distal epiphyseal.
-The structure that is squished in between is the diaphysis - Lining the bone is called periosteum
-The solid and hard structure of the bone is called compact bone and this bone is found in every bone.
Structures found in the diaphysis
Yellow bone marrow, compact bone, militxry cavity, endosteum
Yellow Bone Marrow is found within the mallixary cavity, at the start of life red and yellow bone marrow is found in the cavity
Malliary cavitiy is a cavity (a hole)
Endosteum is the what lines the mallixary cavity
Structure found in both ends of the epiphyseal are spongy bone, epiphyseal plate
Spongy bone is found in both ends of the bones; it is described as honeycombs filled with red merrow
Spongy bone is found below and above the epiphyseal plate.
Epiphyseal plate is squish between spongy bone and is classified as compact bone.
Ossification is the process of bone tissue formation, cartilage becomes bone
Bone Deposit and bone resorption
Occurs at surface of both periosteum and endosteum
Remodeling units: packets of adjacent osteoblast and osteoclasts coordinate remodeling process
Irregular Bones
Different shaped bones that are ridged or abstract
Examples are the pelvic and vertrae
Short Bones
Cube-like bones, ex: wrist and ankels (carpals and tarsals and the calcaneus)
Long Bones
Longer bones bigger in length rather than width, ex: limbs
Treatement is called reduction (realignment of the broken parts)
Closed reduction means to have a physcian manipulate to the correct position
Open reduction: to surgically pin the bones in place
Immobilization, to align it with a cast or traction so it can heal
However there is a process
Classification of fractures:
Rickets
Results in bowed legs and other bone deformities because bones ends are enlarged and abnormally long
osteoporosis
Is group of diseases in which bone resorption exceeds deposit
mass declines causes brittle bones
Osteomalacia
Poorly mineralized
Osteoid is produced, but calcium salts not adequately deposited
Soft bones
Pain by any pressure applied
paget's disease
A deforming disease, due to bone rapiadly or slowly depost and resorption causes for growth to be rapid but poorly
Microscopic anatomy of bones
Cartilage
Formation of bones
- Hyaline cartilage
Most wider spread and has the ability to support, resist and stretch + recoil
Found everywhere, but most abundant in the joints, costal (ribs), respiratory support, and the tip of the nose
2.Elastic Cartilage
Same and hyaline but is makes up the structure of of the ear.
3.Fibrocartilage
Thick collegen fibers that is even more resistent and is found in the posterior of the body (spine)
Appositional growth
New matrix is form on top of the existing bone
Interstitial growth
New matrix is form with in the already existing bone
Flat Bones:
As the name implies the bones are thinned but also curved
ex: Sternum
Periosteum
Endosteum
Covers the external part of the bone
Fibrous Layer: most superficial layer consists of dense irregular connective tissue consisting of fibers that sucure the bone matrix: known as sharpey's fibers
Osteogenic layer: inner layer that constains the osteogenic stem that creates most of all bone cells
Characteristics:
Lines the internal cavities of the bone
Contains osteogenic cells that can develop into other bones
Organic findings with the bone
Osteogenic Cells (shape shifter)
Red Marrow
Found in the heads of humorous and femur but areas that contian the most red bone marrow is the diploe and the pelvic area
Osteoblast (most actively dividing/filled with energy)
osteocytes ( mature/helps maintain rather than create/ grandparents)
Bone-Lining Cells (parents)
osteoclast (the destroyer)
Flat cells on bone surfaces believed to also help maintain matrix (almost always across osteocytes)
Mature bone cells in lacunae that no longer divide (stationed)
helps to maintain bone matrix, which helps protect against stress or strain
Called Osteoprogenitor Cells
Constantly dividing stem cells in the linings of the bones
When they are stimulates, they can form into osteoblast or even bone-lining cells
Bone-forming cells that secrete unmineralized bone matrix called osteoid
Derived from the same hematopoietic stem cells that become macrophages
giant, multinucleate cells function in bone resorption (the breakdown of the bone)
most active osteoclast is in areas called resorption bays
Osteoid
Osteoid is made up of collagen and calcuim-binding proteins (more like support)
Collegen makes up 90% of bone protein
Compact bone
Called Lamellar Bone
Made of:
Osteo (Haversian system)
Canals and Canaliculi
Interstitial and Circumferential Lamellae
Canals and Canaliculi
Interstitial and Circumferential Lamellae
Osteo (Haversian system)
Refers to just a part of the compact bone (a unit)
Characteristics:
A elongated cylinder that runs along parallel
The rings surrounding the matrix is called the lamellae
Lamellae
Lamella contain collagen fibers that run in different direction in adjacent rings
Withstands stress
Bone salts are found between collagen fibers
Canaliculi: think canales that connec the lacunaw to each other and then the central canal
Central (Haversian) canal, runs through the core of osteon, houses blood vessels and nerve fibers
Perforating (Volkmann's) canals, canals lining the endosteum that occurs at a right angles to the central canal (connects the blood vessels and nerves of the periosteum, medullary cavity and the central canal
Lacunae: small cavities that contain osteocytes
Osteoblast that secretes the bone matrix maintain contact with each other and osteocytes via cell projections with gap junctions
Intramembranous Ossification
Bone Develops from fibrous membrane
bones are called membrane bones
creates frontal, parietal, occipital, temporal, and clavicle bones
Endochondral Ossification
bone forms by replacing hyaline cartilage
bones are called cartilage (endochondral) bones
form most of skeleton in adult hood
Bone deposited, the new bone matrix is deposited by osteblasts
bone resorption is made by the function of osteoclasts
Dig depressions or groves as they break down matrix
secrete lysosomal enzymes and protons that digest matrix
acidity converts calcium salts to soluble forms
Osteoclasts also phagocytize demineralized matrix and dead osteocytes
Can be classified by position
NonDisplaced, ends retain normal position
Displaced: out of alignment
Completeness of break
Incomplete: not broken all the way through
Complete: all the way through
Penetration of the skin
Open: skin is penetrated
Closed: not penetrated
Can be classified by location, external appearance or the degree of the break
Type of fracture:
Spiral ragged break (unorgainized)
Epiphyseal
Diaphysis and epiphysis are broken off
Compression, bone crush
Depressed: Broken bone inwards
Comminuted
Many fragments
Greenstick: Bent bone and a incomplete bone
can happen with force, but it more catastrophic with the elderly due to brittle bones
Crushing force
Twisting force, common with sport fracture
may happen more if cartilage cells are dying and calcification of the matrix is occuring
in falls but more common in children
skull fracture
- Bony callus formation
Within a wekk, new trabeculae appear in the firbocartilaginous callus
Callus is converted to bony (hard) callus of spongy bone
Bony callus formation continues for about two months until firm union form
- Bone remodeling
Compact bone is laid down again to reconstruct shaft walls
the final product resembles original structure
- Fibrocartilaginous callus formation
Cappollaries grow into hematoma
Phagocytic cells clear debris
Fibroblasts secrete collagen fibers to span break and connect ends
Fibroblast, cartilage, and osteogenic cells egin reconstruction of bone
- create cartilage matrix of repair tissue
- osteoblasts from spongy bone within matrix
This mass of repair tissue is called fribrocartilaginous callus
1, Hematoma formation:
A blood vessle breaks and forms a blood "pimple)
Site is swollen, painful, and inflamed
Caused by of a vitamin deficiency or insufficient dietary calcium
risk factors for osteoporosis
Often aged, postmenopausal women
estrogen plays a role in bone density, so when levels drop at menopause women have a higher risk
life style also plays a role in developing this diseases
Medicina and more natural elements can treat this diseases
Joints are also called articulations: sites where two or more bones meet
The functions of joints: give skeleton moility and hold skeleton togehter without causing pain
Two classifications
Functional classification: three types based on movement joint allows
- Synarthroses:
- amphiarthroses
- Diarthroses
Structural: three types based on what material binds the joints and whether a cavity is present
- Fibrous
- Cartilaginous
- Synovial
One of the classifications of the joints indicates how much it can move, they are defined as
1.Synarthoroses: Immovable joints
- Amphiarthroses: slightly movable joints
- Diarthroses: freely movable joints
Cartilaginous
Bones united by cartilage
no joint cavity
not very movable
Two types:
Synchondroses
Symphyses
Synovial Joint
Bones separated by fluid-filled joint cavity
All are diathrotic (freely movable)
Include almost all limb joints
Fibrous
Bones joined by dense fibrous connective tissue
no joint cavity
most are immovable
Three types of fibrous joints
Syndesmoses
gomphoses
Sutures
Found only in the skull
meant to allow growth during youth
these joints become immovable as we age
Completely immovable sutures refer to as synostoses
Bones connected by ligaments, bands of fibrous tissue
Fiber length varies, so movement varies
- Short fiber offer little to no movement
- longer fiber offer a larger range of movement
Peg-in-socket joints
Only examples are the teeth in alveolar sockets
fibrous connection is the periodontal ligament
Symphyses
Fibrocartilage unites bone in symphysis joint - hyaline cartilage also present as articular cartilage on bony surfaces
Symphyses are strong, amphiarthrotic (slightly movable joint)
Synchondroses
Bar or plates of hyaline cartilage unites bones
Almost all are synarthrotic (movable)
Characteristics of Synovial Joints:
Have six general features
allow several types of movements
Stablility is inflenced by three factors
classified into six different types
Have bursae and tendon sheaths associated with them
click to edit
Joint (cynovial) cavity: small, fluid filled potential space that is unique to the synovial joints
Articular Joint Capsul: two layers thick
Synovial fluid viscous, slippery filtrate of plasma and hyaluronic acids
Lubricates and nourishes cartilage
houses phagocytic cells to remove microbes and debris
Articular Cartilage: Consists of hyaline cartilage covering ends of bones- prevents crushing of bone ends
Different types of reinforcing ligaments
Nevers and blood vessels
Nevers detects pain and manages joint position and stretch
capillary beds supply filtrate for synovial fluid
Synovial membrane: loose connective tissue that makes synovial fluid
Fibrous layer: dense irregular connective tissue
Extracapsular outside the capsule
Intracapsular Deep to capsule, covered by synovial membrane
Capsular
Thickened part of fibrous layer
Articular discs (menisci)
Fibrocartilage separates articular surface to match the bone ends to stabilize joint and reduce trauma
Fatty Pads
For cushioing between fibrous layer of capsule and synovial membrane or bone
Bags of synovial fluid that act as oil or lubricating ball earing
Tendon Sheaths: elongated bursae wrapped completely aroud tendons victim to friction
Bursae: reduce friction where ligaments muscles skin, tendons or bones rub together
Pivot
Condylar
Hinge
Saddle
Plane
Ball-and-socket
Grinding
flexion and extension
rotation
Flexion, extension, adduction, and abduction
Adduction , abduction, flexion, and extension
moves in all direction but grinding
-Muscles attach to bone or connective tissue at no fewer than two points
-Muscle contracts causes insertion to move toward origin
-Movements can be transverse, frontal, or sagittal planes
-Range of motion allowed by synovial joint
Nonaxial: Slipping movemtn only
Uniaxial Movement in one plane
Biaxial: movement in two planes
Muiltiaaxial: movement in or around all three plane
-Three general types of movements
griding
angular movements
rotation
Surface of bones glides or slips over another similar surface , ex: joints
Movement along sagittal plane
Flexion: decreases the angle of the joint - moving down
extension: increases the angle of joint - neutral
Hyperextension: movement beyond the anatomical position - extending back
Abduction: movement along frontal plane, away from midline
Adduction: movement along frontal plane, towards midline
involves flexion, abdction,extension, adduction of limb
Medial- towards midline
Lateral- rotation away from midline
Special movement-
supination (radius and ulna parallel) and pronation (radius rotates over ulna)
Dorsiflexion (pushing back) and plantar flexion (extending)
Opposition- grasping
Inversion (moving foor inward) and eversion (moving foot away from medially)
Elevation (lift body) and depression (lower body) of mandible
protraction (moving jaw forward) and retraction (moving away)