Causes
In the SCI population, osteoporosis is likely due to many different factors.
Disuse: lack of mechanical loading on the bone inhibits the stimulation of bone-building cells.
Disordered vasoregulation: sluggish blood flow to limbs may contribute to a decrease in bone mass.
Poor nutritional status: inadequate consumption of a healthy, well balanced diet.
Hormonal alterations (testosterone, PTH, glucocorticoids, calcitonin) that happen as a result of SCI and play a role in the maintenance of bony formation and reabsorption.
Metabolic disturbances in metabolites and acidity of the blood can influence the balance of bony formation and reabsorption.
Autonomic nervous system disregulation caused by the injury leads to poor circulation and altered gas and nutrient exchange at the bone.