HSF week 4

anterolateral movement of the scapula

posterolateral movement of the scapula

movement of the sole of the foot away from the midline

outer layer is the epimysium, then the perimysium which surrounds 10-100 muscle fibres (to form a facicle). each individual muscle fibre is wrapped in endomysium)

in concentric rings

its cross section - not its length

a broad, flat connective tissue linking the muscle belly to a site of attachment. spread over a greater area than a tendon

a line of fibrous tissue where one muscle joins another. often attaches one muscle to another down the middle

compliments the action of a prime mover by adding extra force to the same movement and reducing undesirable or unnecessary movement

fatty tissue, containing veins, lymph vessels and lymph nodes

dense, organised connective tissue. strong, inelastic and usually present in a single layer

a thickening of the deep fascia that holds down tendons

another term for epimysium - the outer layer of a muscle (deep to the deep fascia)

osteons

lamellae arranged into irregular patterns of thin columns called trabeculae

diaphysis

• A - proximal epiphysis 
• B - metaphysis 
• C - Diaphysis 
• D - metaphysis 
• E - distal epiphysis 
• F - articular cartilage 
• G - epiphyseal line
• H - endosteum 
• I - Periosteum

the epiphyseal plate

nourishes the external aspects of the bone. has an active role in repeairing damage to the bone.

collagen

yellow bone marrow

the periosteal and epiphyseal arteries

in the periosteum, not within the bone

• osteoblasts are bone-building cells - they synthesise and secrete the organic ECM components of the bon
• osteoclasts break down bone - they release eznymes and acids that digest collagen and minerals that exist in the ECM

intramembranous ossification and endochondral ossification

• bone develops directly from the mesenchyme. mesenchymal models of bone form during the embryonic period and direct ossification occurs in the foetal period. 
• First the ossification centre develops, which is where bone will form 
• - specific chemicals signals will cause the mesenchymal cells to clump together and differentiate
• - and osteoblasts will begin secreting ECM 
• once the ecm is surrounding cells, calcium and other minerals are secreted (calcification) 
• - trabeculae will form and fuse around the blood vessels 
• - the mesenchyme at the periphery of the forming bone will condense and develop into the periosteum
• - eventually a layer of compact bone will replace the outer layer of spongy bone

• first chemical messengers cause cells in the mesenchyme to condense and differentiate into chondroblasts, which secrete ECM to form a cartilage model of the bone 
• in the centre region of the cartilage, it hypertrophies (cells increase in size) and calcifies 
• periosteal capillaries grow into the calcified cartilage 
• blood supplied by the capillaries initiate the primary ossification centre
• ossification centre grows, replacing hyaline cartilage with bone 
• as it grows, osteoclasts come in and break down some of the newly formed bone, leaving the medullary cavity in the diaphysis 
• branches of the epiphyseal artery will enter the still-forming bone at the proximal and distal epiphysis, triggering the formation of a secondary ossification centre in the ends of the long bone
• - the growth of the secondary ossification centre will occur pretty much the same as the first, except spongy bone remains in the middle, rather than being broken down to form the medullary cavity

hyaline cartilage

• zone of resting cartilage (nearest to epiphysis)
•  - doesnt function in bone growth and instead anchors the plate to the epiphysis 
• zone of proliferating cartilage
•  - chondrocytes here proliferate and produce ECM  
•  - they replace dead cells on the diaphyseal side 
• zone of hypertrophic cartilage 
•  - made up of maturing chondrocytes
• zone of calcified cartilage 
•  - thin
•  - consists of dead chondrocytes (as the ECM is calcified)
•  - osteoblasts dissolve the calcified cartilage and capillaries (and more osteoblasts) invade the area (and lay down new ECM, replacing the cartilage)

the increase in the diameter of the bone

• periosteal cells the periphery of the bone differentiate into osteoblasts (secrete ECM minerals etc)
• the osteoblasts surrounded by the ECM will differentiate into osteocytes - mature bone cells 
• some of the old bone lining the medullary cavity is destroyed by osteoclasts (so the medullary cavity enlarges as the bone thickens)

thoracic and sacral

lumbar and cervical

• all abnormal spinal curvatures
• kyphosis is excessive primary curvature
• lordisis is excessive secondary curvature
• scoliosis is deviation of the spine from the midline

the epiphyseal ring (compact bone)

the pedicles and the lamina

has 2 laterally positioned holes/foramen and a bifid spinous process

the intevertbral foramen. the spinal roots of the superior vertebrae passes through here

• annulus fibrosis
• - consists of concentric lamellae of collagen
• nucleus pulposis 
• - gelatinous consistency

the zygapophyseal joints. plane synovial joints

• A - posterior longitudinal ligament
• B - anterior longitudinal ligament
• C - interspinous ligament
• D - ligamentum flavum
• E -  supraspinous ligament
• F - ligamentum flavum

• attach to and act on the upper limb
•  - origin is the back, insertion is the upper limb
• includes levator scapulae, rhombus major and minor, latissimus dorsi

• attach to and act on the back 
• - includes erector spinae and transversopinalis

nothing - it is avascular

hyaline, elastic (such as epiglottis) and fibrocartilage (such as anulus fibrosis of the intevertbral disc)

synovial, fibrous and cartilaginous

• sutures - thin layer of dense connective tissue (only present between the bones of the cranium)
• syndesmosis - occurs where 2 adjacent bones are linked by a membrane (such as the interosseous membrane between the radius and ulna)
• gomphosis - short collagen fibres running between the root of a tooth and their bony sockets in the jaw - technically a type of syndesmosis

• synchondroses or primary - bones are united by hyaline cartilage (such as the epiphyseal plate or the first joint between the rib and sternum
• symphyses or secondary - bones that are joined by fibrocartilage (such as intervertebral discs and the pubic symphysis)

the synovial membrane (inner layer of the joint capsule)

filtered interstial fluid, from blood plasma

• plane joints - produces sliding movements (sternoclavicular, intercarpal and vertebracostal joints)
• hinge joints - produces opening and closing movements (elbow and ankle)
• pivot joints - allows for rotational movements (such as the radioulnar joint that allows us to flip our palms)
• condylar/ellipsoid joint - produces flexion, extension, adduction and abduction (radiocarpal joint that allows us to move our wrist and knuckle)
• saddle joint -  same movement plane as conyloid joint (except while a condyloid joint is limited in one plane, saddle joint allows relatively even movement in all of these planes) (incoludes carpometacarpal thumb joint) 
• ball and socket joint - flexion, extension, adduction, abduction, circumduction and rotation (glenohumeral joint)