Ross Leslie The Skeletal System p.7

The Long Bone

Articular Cartilage- smooth, glassy cartilage allows bone to glide past each other smooth surface and decrease friction between ones.

Periosteum- membrane that covers bone, attachment site for muscle, tendons, and ligaments, and osteoblast production after injury

Epiphysis- end of long bone, proximal, distal, compact bone enclosing spongy bone and contain red bone marrow- hematopoietic

Endosteum- Thin membrane lining Medullary cavity, connective tissue, and contain both.

Diaphysis- shaft of compact bone, covered with thin connective tissue called Periosteum, and contain Medullary cavity hollow area filled with yellow bone marrow [ fat storage]

Medullary Cavity- center of long bone, contain yellow marrow [ mostly fat] in adults, and contain red marrow [ blood cell information] in infants

Microscopic of Compact bone

Osteocytes- mature bone cells, are osteoblasts that have become trapped in lacunae; they maintain the bone matrix, and star shaped, they are old/ matrix osteoblasts

Osteoclasts- bone destroying, giant cells that participate in bone resorption [ reabsorb]; mainly found on outside of bone, release minerals into blood stream by breaking down

Osteoblast- bone building, found in periosteum and endosteum; secrete matrix [ collagen and ground substance], and blast growth

Compact Bone- appears solid, network of osteons = structural unit of compact bone, calcium matrix surrounding collagen fibers; strong but flexible, and an arranged in rings surrounding central canal

Bone Remodeling

Control of Remodeling- Hormonal Control-occurs of 2 negative feedback loop, low blood Ca++ levels ----> PTH release----> osteoclasts destroy bone
High blood Ca++ levels ----> Calcitonin release ----> osteoblasts despite bone

b) Response to Stress and Pressure- flormonal control ignores the needs of the skeleton Wolff's Law holds that a bone grows/ remodels itself in response to the forces and stress exerted upon it

Bone Deposit-occurs when bones are injured, to make the bone stronger for a short period of time but will eventually reach similar strength as the bone surrounding it

Bone Reabsorption- occurs in response to the calcium needs of the body. If there us a shortage of calcium, the osteoclasts will dissolve/absorb bone so that calcium can be sent to the muscles and nerves [ increase blood calcium level]

Bone Remodeling- bone is often being made and /or reabsorbed at the periosteum/ endosperm which results in the remodeling of the bone

Bone Fracture

Depresses Fracture- bone is pressed inward or denied in and common in skull fracture [ where they hit over the head with a hammer, bat, etc

Spiral Fracture- ragged break from a twisting force appeared to the bone and common sport injury or can indicate possible child abuse

Compression Fracture- bone is crushed and collapsed on itself, common invertebrae and common in elderly patient with osteoporosis

Impacted Fracture- broken bone forced into each other and common in long bones, and impact from the outstretched arm to break a fall

Comminuted Fracture- broken into more than 3 pieces

Greenstick Fracture- bones break incompletely and common in children whose bones have not yet fully ossified

movement of synovial membrane

Ball- and- socket- very wide range that is impossible like shoulders and hip joints

Condylar Joint- a variety of motions like joints between a metacarpal and a phalange

Plane joint- a back- and - fourth motion like the wrist and ankle. Also between vertebrae are gliding joints

Hinge joint- a surface fits into a concave surface that is found in the elbow and phalange

Pivot joint- a surface that rotates within a ring bone and fibrous tissue like between proximal ends of the radius and ulna and the atlas and dens f rage axis

Saddle joint- permits movement in two planes like between trapezium and the metacarpals of the thumbs

Differences of Male and Female Pelvis

The female pelvis is larger and broader than the male pelvis. It indicates that the female pelvis is much taller ( owing to a higher iliac crest), narrower, and more compact than the male pelvis

The male pelvis is the distance between the ischium bones which is smaller in the male than females and it is shape inlet is more heart shaped

Bone Repair

Hematoma- blood filled swelling caused by the broken blood vessels and signals released to start the process

Fibrocartilage callus- a temporary "bridge" or connective between end of broken bone

Bony- eventually replaced by the hard bone on a process called remodeling

Fibrocartilage- replaced by a bony callus- tougher and more stable

Types of bone

Flat Bone- flat, thin boned, often curved ( skull plates, ribs, sternum etc)

Irregular Bones- odd, irregular shapes ( pelvis, vertebrae, scapula etc)

Short Bone- square or cube shaped ( wrist, ankle, patella etc)

Appendicular skeleton- 126 bones, upper & lower limbs ( shoulder bones & hip bones)

Long Bone- longer than they are wide ( arms, legs, phalanges etc.)

Compact Bone- very solid & smooth; outer layer of bones

Axial skeleton- 80 bones, long axis of the body, skull, vertebra & thorax

Spongy Bone- contain small " needles" of bone called spicules or trabecular with open holes/spaces

Joints

Fibrous joint- dense connective tissue, no movement; fibrous connective tissue grows between two bones ( sutures of skull)

Cartilaginous Joint- cartilage connects articulating bones; pubic symphysis or intervertebral disk in spine

Synovial joint- most joints are in this class; free movement

Articular Cartilage- a " rubber shock absorber" that provides a smooth frictionless surface

Synarthroses- immovable joints

Amphiarthroses- slightly moveable joints

Diarthoses- freely moveable joints

Articulation of joints- holds bone together; allows for mobility

Joint Capsule & Ligaments- fibrous connective tissue connects the ends of two joining bones

Synovial membrane- secretes synovial fluid that fills the joint cavity & decrease friction

Synovial cavity- spaces inside a joint capsule between two bones, filled with synovial fluid

Bursae- flattened fibrous sacs, lined with synovial membrane, filled with synovial fluid

Name all the Bones

Radius- bone on thumb, side of lower arm

Ulna- bone on little finger, side of lower arm, also known as funny bone

Clavicle- collarbones, only joints between shoulder girdle & axial skeleton

Scapula- shoulder blades, scapula plus clavicle forms shoulder girdle

Humerus- upper arm bone

Metacarpals- form framework of palm of hand

Phalanges- finger bones; three each finger, two each thumb

True ribs- upper seven pairs, attached to sternum by costal cartilage

False ribs- lower five ribs, lowest pair do not attach to sternum

Coccyx- in child, three to five separate vertebrae; in adults, fused into one; ends of spinal region

Sacrum- in child, five separate vertebrae; in adults, fused into one

Floating ribs- next three pairs attached to sternum by costal cartilage

Lumbar vertebrae- next five vertebrae, are in small of back

Cervical- upper seven vertebrae in neck region

Thoracic vertebrae- next 12 vertebrae, ribs attach to these

Patella- kneecap

Maxilla- upper jawbones

xiphoid process- lower end of sternum

Fibula- long slender bone of lateral side of lower leg

Pubic bone- makes up the pelvis

Tibia- shinbone

Femur- thigh or upper leg bone

Metatarsal- form part of foot to which toes are attached

Nasal- small bones that form upper part of bridge of nose

Synovial Membrane Disorders

Lateral flexion- bending head, neck, or trunk to side

Rotation- moving a part around its axis

Pronation- rotation of forearm so that palm is downward or posterior

Abduction- moving a part away from midline

Hyperextebsion- extend beyond anatomical position

Extension- increasing the angle at a joint

Flexion- decreasing angle at the joint

Dorsiflexion- flexion of ankle brings foot farther away from shin

Adduction- moving a part towards midline

Circumduction- end of part follows a circular path

Supination- rotation of forearm so that palm is upward of anterior