(January 21, 2003) - Bethesda, MD As this year draws to a close, some ten thousand Americans will have incurred a non-fatal spinal cord injury (SCI), joining about 200,000 others similarly disabled. The peak season for spinal cord injury is in the summer and is caused primarily by motor vehicle accidents, falls, sports injuries and violence. Paraplegia (the loss of sensation and or movement in the legs and part of the trunk) affects 47 percent of people with spinal cord injuries; quadriplegia (affecting all four limbs and the trunk) affects 52 percent. The actor Christopher Reeves, for example, is a quadriplegic.
SCIs are classified as primary or secondary. Primary SCIs are caused by mechanical disruption, transection, extradural pathology (spinal epidural hematomas or abscesses), or distraction of neural elements. This usually occurs with fracture and/or dislocation of the spine. However, primary SCI may occur in the absence of spinal fracture or dislocation. Penetrating injuries due to bullets or weapons may also cause primary SCI. More commonly, displaced bony fragments cause penetrating spinal cord or segmental spinal nerve injuries.
Vascular injury to the spinal cord can be caused by arterial disruption, arterial thrombosis, or hypoperfusion due to shock. These are the major causes of secondary SCI; anoxic or hypoxic effects compound the extent of the injury. The science behind vascular performance or blood flow is that perfusion pressure and vascular resistance govern blood flow to tissue. Because mean arterial pressure and venous pressure are normally maintained within narrow limits, blood flow control is accomplished in large part by variation in vascular resistance.
Vascular resistance is essentially under dual control, through systemic control via the autonomic nervous system and humoral factors and by local control via the conditions in the immediate vicinity of the blood vessels. The importance of syPage: 1 2 3 4 5 Related biology news :1
Contact: Donna Krupa
American Physiological Society
. Nerve cells guided to repair spinal damage: Technique2
. Mitochondria in spinal cords is ALS target according to UCSD medical researchers3
. Yale researchers receive $4.5 million grant to study spinal cord repair4
. Study of ProCord for neurologically complete spinal cord injury5
. Combination therapy dramatically improves function after spinal cord injury in rats6
. Naropin now approved for intrathecal (spinal) administration in the European Union (EU)7
. Chemical gradient steers nerve growth in spinal cord8
. Dying nerves cause even more harm after spinal cord injury9
. Gene-expression atlas will provide new direction for brain and spinal-cord studies10
. New gene for rare inherited paralysis may aid other spinal cord research, too11
. Acorda Therapeutics begins Phase 3 trials of Fampridine-SR for chronic spinal cord injury