Directional Terms, Skeletal Anatomy Flashcards
What is anatomical position and what does it look like?
Starting reference point Universally accepted Standing erect, facing forward, arms at sides, palms facing forward, legs straight, heels feet and great toes parallel to each other
Lateral
Away from midline
Medial
Towards the midline
Distal
Further from specific region (distant)
Proximal
Closer to specific region (approximately, close proximity)
Anterior
In front of/front half of body
Posterior
Behind/back half of body
Superior
Above
Inferior
Below
Supine
Lying on back (bench pressing)
Prone
Lying face down (push-uping)
Median/midsagittal/sagittal plane
Vertical plane that cuts body into left and right halves
Coronal/frontal plane
Vertical plane that cuts body into front and back halves
Transverse/horizontal plane
Horizontal plane that cuts body into top and bottom halves
Centre of gravity
Where all 3 planes meet
Flexion
Reduces angle between 2 bones at a joint
Extension
Increases angle between 2 bones at a joint
Dorsiflexion
Bring toes and top of foot towards leg
Plantar flexion
Pointing toes down “planting foot”
Abduction
Moving segment away from midline
Adduction
Moving segment towards midline
Circumduction
Cone motion, but is not rotation flexion/extension + abduction/adduction
Rotation
Turning bone on its horizontal axis
Medial rotation
Rotation towards midline
Lateral rotation
Rotation away from midline
Pronation
When palm is turned to face posteriorly
Supination
When palm is turned to face anteriorly (hold a bowl of soup)
Inversion
When sole is turned in (ankle goes over)
Eversion
When sole is turned outward
What are the functions of the skeleton?
-Support tissues and provide a framework for the body -Protect organs -Provide a stored reserve of phosphorus and calcium (which may be drawn upon in time of need) -Bone marrow is the site of red blood cell production -Provide levers on which muscles pull to create movement
Name the categories of bone
Long, short, flat, irregular Sesamoid, wormian
Long bones
Any bone whose length greatly exceeds its diameter Provide levers for movement Tubular shell with a cavity in the middle
What are some examples of long bones?
Tibia, fibula, ulna, radius, HUMERUS, FEMUR
Short bones
Serve as good shock absorbers No marrow cavity
What are some examples of short bones?
Tarsals, carpals
Flat bones
Largely protect underlying organs No marrow cavity
What are some examples of flat bones?
Cranium, ribs, scapula, sternum, clavicle
Irregular shaped bones
Cannot be put in other groups because they fulfil special functions No marrow cavity
What are some examples of irregular shaped bones?
Facial bones and vertebrae
Sesamoid bones
Form in tendons
Give an example of a sesamoid bone.
Patella
What is wormian bone and where can it be found?
Small jigsaw fragments which are found along sutures of skull.
What are the 2 types of bone?
Compact/cortical bone and spongy/cancellous bone
Compact/ cortical bone
Dense/smooth appearance On the outside
Spongy/cancellous bone
Composed out of small needle-like pieces of bone and has lots of open space On the inside
List examples of movements in the frontal axis.
Cartwheel, jumping jacks
List examples of movements in the median axis.
Flip, summersault, sit up, dive, walking
List examples of movements in the horizontal/transverse axis.
Spin, pirouette
What makes up the structure of a long bone?
Diaphysis, periosteum, epiphysis, epiphyseal growth plates, articular cartilage, yellow bone marrow, red bone marrow
Diaphysis
Shaft that runs the bone’s length
Periosteum
Covers and protects the diaphysis
Epiphyses
Ends of a long bone Contains a thin layer of compact bones surrounding an area filled with spongy bone
Epiphyseal growth plates
Seen in young developing bone (replaced by epiphyseal line when ossified in adult bones) Area of lengthwise bone growth Where the diaphysis meets the epiphyses
Articular cartilage
Covers the epiphyses Provides a smooth/slippery surface for articulation (the joint)
Yellow bone marrow
Storage of fat
Red bone marrow
Forms blood cells
What are bones composed of?
Calcium carbonate & calcium phosphate, collagen, water
What role do calcium carbonate & calcium phosphate have in the composition of bones?
60-70% of bone weight
Provide much of bone’s stiffness and resistance to pressing or squeezing forces
What role does collagen play in the composition of bones?
Collagen is a protien
It gives bone it’s flexability and contributes to its ability to resist pulling and stretching forces
What effect does fitness have on bone?
When subjected to regular physical activity and habitual loads, they become denser and more mineralized. Inactivity works in the opposite direction.
What is ossification and how does it happen?
Bone tissues begin as soft cartilaginous tissues that are predominantly collagen based. The collagen acts as a flexible framework for the bone. The calcium later acts as drywall, filling in all the gaps to harden the bone. This is called ossification.
Why is ossification necessary for human survival?
The cranium is compressed at birth and later ossifies to ensure that brain is in a solid case.
Why is weightlifting at a young age detrimental to health?
Growth plates are not ossified until adolescence or adulthood, when growing is complete, so they are the most succeptable place of injury.
How do irregular shaped bones ossify?
From the inside outwards (sutures on cranium do not ossify until 2 years of age)
For what two reasons do bones become more brittle?
Loss of collagen
Osteoporosis
What is osteoporosis?
Lack of calcium due to deficiency in diet or inability to absorb calcium based on hormones.
How can osteoporosis be prevented?
Diet high in calcium, INCREASED PHYSICAL ACTIVITY, possibility of hormone replacement (with doctor’s prescription)
