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Your Bones in Space ASTRONOMY AND SPACE SCIENCE
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Hypogravitational Osteoporosis: A review of literature.
By Lambert Titus Parker. May 19 1987. (GEnie Spaceport)
Osteoporosis: a condition characterized by an absolute decrease in the
amount of bone present to a level below which it is capable of maintaining
the structural integrity of the skeleton.
To state the obvious, Human beings have evolved under Earth's gravity
'1G'. Our musculoskeleton system have developed to help us navigate in
this gravitational field, endowed with ability to adapt as needed under
various stress, strains and available energy requirement. The system
consists of Bone a highly specialized and dynamic supporting tissue which
provides the vertebrates its rigid infrastructure. It consists of specialized
connective tissue cells called osteocytes and a matrix consisting of
organic fibers held together by an organic cement which gives bone its
tenacity, elasticity and its resilience. It also has an inorganic component
located in the cement between the fibers consisting of calcium phosphate
[85%]; Calcium carbonate [10%] ; others [5%] which give it the hardness
and rigidity.
A machine to measure bone density to check for ost...
Osteoblasts actively synthesizing osteoid.
Bone growth source: http://training.seer.cancer.go...Other than providing the rigid infrastructure, it protects
vital organs like the brain], serves as a complex lever system, acts as a
storage area for calcium which is vital for human metabolism, houses the
bone marrow within its mid cavity and to top it all it is capable of changing
its architecture and mass in response to outside and inner stress. It
is this dynamic remodeling of bone which is of primary interest in microgravity.
To feel the impact of this dynamicity it should be noted that a bone
remodeling unit [a coupled phenomena of bone reabsorption and bone formation]
is initiated and another finished about every ten seconds in a healthy
adult. This dynamic system responds to mechanical stress or...