bones and cartilage
TRANSCRIPT
Bones, Cartilages and Joints
Objectives1. Determine the structure of the bones 1.1 Classify bones as to size and shape 1.2 Contrast compact from spongy bone 1.3 Locate the axial and appendicular bone 1.4 Identify the parts of long bones 1.5 List the functions of the bones 1.6 Give the types of bone formation 1.7 Discuss the process of bone healing
2 Determine the types of cartilage 2.1 Name the composition of the intracellular substance 2.2 Identify the histologic features of each type 2.3 Give the functions of each type 3. Describe the different types of Joints 3.1 Cite locations of joints 3.2 Demonstrate joint movements4. Identify some abnormalities in bones and joints
Tissues Epithelial Connective > Bone > Cartilage > Fibrous connective tissue > Blood Muscle Nerve
BonesComposition Cells: osteoblasts, osteoclasts, osteocytes Collagen fibers - to withstand shearing forces Dense mineralized ground substance: inorganic salts of calcium and phosphate = hydroxyapatite - for weight bearing
Bone cells
Functions of bones
Description
Movement Maintain or change position of body parts by interacting with skeletal muscles
Protection Enclose and protect the brain, lungs, and other organs
Support Support and anchor musclesMineral storage
Serve as a depot for storing and withdrawing mineral ions; indirectly helps maintain body fluids and support metabolic activities
Blood cell formation
Site for production of red blood cells and other blood cells
Types of bonesAccording to Density: compact and spongy Size and shape: long, short, flat & irregular Location: axial and appendicular
axial
appendicular
Types of bones according to size and shape1. Long = bones of the upper and lower
extremities2. Short = bones of the wrist and ankle3. Flat = clavicle, sternum, scapula and pelvis4. Irregular = vertebrae and facial bones
Long bones
Parts of Long Bones
Spongycompact
HumerusRadiusUlnaMetacarpalsPhalangesFemurTibiaFibulaMetatarsalsToes
Bone density Spongy bone - cancellous - consists of trabeculae - found within the epiphysis and metaphysis
Compact bone – cortical - usually found on the bone surface - making up most of the diaphysis
Organization of lamella in compact bone1. Haversian system – osteons - long cylinders running parallel to the long axis of the diaphysis2. Interstitial lamella3. Outer and inner circumferentil lamellae
Short bones = resemble blocks
Flat bones Composed of 2 thin plates of compact bones with
central region of spongy bone Skull bones, scapulae, ribs, sternum and pelvic
bones
Clavicle
Ribs
Irregular bonesPatella
Blue: Vomer (1) Yellow: Maxilla (2) Purple: Mandible (1) Pink: Nasal bones (2) Red: Palatine bones (2) Bright blue: Lacrimal bones (2) Dark green: Zygomatic bones (2) Bright green: Inferior nasal concha (2)
Bone formation
Intramembranous ossification
Endochondral ossification
Epiphyseal Plate
Bone remode
Wolff’s Law
Bone formation after fracture
Cartilage Supporting connective tissue with tensile strength Composition of ground substance > chondroitin sulfate > keratin sulfate > chondronectin > collagen: Type I = fibrocartilage Type II = hyaline and elastic no blood and nerve supply
Produced by chondroblasts to become chondrocytes
• Growth of Cartilage - Appositional growth results in outward expansion due to the production of cartilage matrix on the outside of the tissue - Interstitial growth results in expansion from within the cartilage matrix due to division of lacunae-bound chondrocytes and secretion of matrix
Types of cartilage
1. Hyaline - most common, found in
the ribs, nose, larynx, trachea - a precursor of bone2. Fibro - is found in vertebral
discs, joint capsules, ligaments
3. Elastic - is found in the external ear, and epiglottis
Hyaline cartilage• consists of living chondrocytes
situated far apart in fluid-filled lacunae
• contains a number of collagenous fibers
• occurs in trachea, the larynx, the tip of the nose, in the connection between the ribs and the breastbone
• provides a sliding area which reduces friction
Elastic cartilage has interlacing fibers contains many yellow elastic
fibers lying in solid matrix found in the epiglottis,
external ear, and eustachian tube
maintains the shape of a structure while allowing great flexibility
Fibrous cartilage dense collagen fibers and limited amount of ground substance chondrocytes are between the bundles of collagen has great tensile strength predominates in body areas that bear great
amounts of weight Found in the pubic symphysis.skull bones, and
disks between the vertebrae, in the tendonous and ligamentous insertions
Functions of fibrocartilage:1. Shock absorbers – cartilage between the
adjacent vertebrae while we run or walk
2. Provides sturdiness without impeding movement
- forms a firm joint between bones but still allows for a reasonable degree of movement
3. Deepens sockets – in articular cavities (such as the ball-and-socket joints in the hip and shoulder regions) white fibrocartilage deepens the sockets to make dislocation less possible
Characteristic
Cartilage Bone
Ground substance component
Chondroitin sulfate, keratin sulfate, chondro-nectin, no mineral component
Chondroitin sulfate, keratin sulfate, osteocalrin, osteo-pontin, sialoprotein, hydroxyapatite, citrate, carbonate
Collagen types
Type I fibrocar-tilageType II hyaline & elastic
Type I
Blood vessels
Absent, nutrient via diffusion
Present
Nerves Absent PresentRepair (regene-ration capacity)
Low High
Mitosis Chondroblasts YesChondrocytes Yes
Osteoprogenitor YesOsteoblasts NoOsteocytes No
Communication
No junctions between chondrocytes
Gap junctions between osteocytes
Hormonal influence
T3, T4, testos- terone, GH, cortisone, estradiol
PTH, Calcitonin, GH, Estrogens, Androgens
Joints Articulation Where bones come in contact with each other
Basic types of joints 1. those that have little or no movement a. Synarthroses - immovable b. Amphiarthroses - semimovable 2. those that are freely movable = Diarthroses
Joints that restrict movement1. Fibrous joints – bones are joined together by
strong fibrous tissues = Synarthroses a. Sutures b. Syndesmoses c. Gomphoses2. Cartilaginous joints – bones are joined together by cartilaginous material = Amphiarthroses a. Symphysis b. Synchrondroses
Sutures
Syndesmoses Between radius and
ulna
Between tibia and fibula
Gomphoses Between the root of tooth and jaw (upper = maxilla and lower = mandible)
Amphiarthroses Slightly movable joints Consists of two adjacent bone separated
by substantial amount of hyaline cartilage
Some cases bones are separated by ligaments
Symphysis pubis Intervertebral discs
Manubriosternal joint
Synchondrosis joint
Sacroiliac joint
Joints that allow movement Diarthroses Synovial joints – 2 bones encased within a cavity Architecture of synovial joints 1. surface where bones come in contact and move against each other is covered by articular or hyaline cartilage 2. surrounded by a strong fibrous joint capsule 3. contains joint cavity within the fibrous capsule 4. non epithelial synovial membrane secretes synovial fluid
Movements by synovial joints:- Axis of motion: = Nonaxial - slipping movements = Uniaxial - movement in one plane; phalanges, radius/ulna, femur/tibia = Biaxial - movement in two planes; occipital bone/atlas = Multiaxial - movement in three planes; scapula/humerus, and coxal bone/ femur
Types of synovial joints1. Plane or gliding2. Hinge3. Pivot4. Condyloid5. Saddle6. Ball and socket
plane
condyloid
Bursa Closed fluid-filled sac Lined with synovial membranes Commonly found between the skin and bony prominences Assist the movement of tendons that pass over bones
Joint movements Flexion – Extension Abduction – adduction Pronation – supination Median rotation – lateral rotation Elevation – depression Protraction – retraction Dorsiflexion – plantar flexion Eversion – inversion
Fracture – discontinuity with the anatomy of boneSprain - stretching/tearing of a ligament
Dislocation - (luxation), bones forced out of their normal positionBursitis - inflammation of bursa
Arthritis - inflammatory or degenerative disease; synovial membrane thickens, fluid production decreases, increase in friction and pain
Types of arthritis:• Osteo arthritis - degenerative• Rheumatoid arthritis - autoimmune• Gouty arthritis - uric acid
accumulation
Synovitis - inflammation of synovial membrane
Tendinitis - inflammation of tendon sheaths
Signs and symptoms of arthritispainswellingstiffnessfatiguefever rashes lumps under the skin limitation of body movement
References Alcamo, Edward: Anatomy and Physiology The
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