SCI Flashcards
Pathophysiology of SCI.
Physical alteration of cord/cutting of cord fibers.
Cord intact with auto-destructive process.
Cord intact with vascular compromise.
Non-traumatic etiology of SCI.
Vascular malformations: aneurism, thrombus, embolism, AV malformation, hemorrhage.
Vertebral degeneration/subluxation: osteoporosis, severe kyphosis, rheumatoid arthritis, kyphoscoliosis, stenosis, Paget’s disease, AA dislocation.
Primary or secondary neoplasms: multiple myeloma, myeloma; metastases from lung or breast.
Infections: myelitis, syphilis, Guillian-Barre
Abscess: necrosis of spinal cord tissue
Congenital defect - Spina bifida
Other: myelopathy secondary to radiation therapy, MS, ALS
What are the two highest traumatic MOIs for SCI?
Falls and MVAs
Majority of SCIs occur at what levels of the spinal cord?
C4-C6 and then at the T12-L1 junction
What are the factors which affect vertebral injury?
Direction of force applied to system
Position of the person’s head at time of injury
Magnitude, rate of application, and duration of injuring force
Point of application
The three most common damaging forces in c-spine include:
flexion, vertical loading, and extension.
Hyperflexion of the c-spine typically occurs around what levels?
C5-C7
What are secondary injuries that occur from a hyperflexion injury in the c-spine?
Wedge fracture of vertebral body, tearing of posterior ligaments, anterior dislocation of vertebral body, disruption of disc, fractures of posterior elements (spinous processes, laminae, and pedicle).
Neurologic damage that can occur from a flexion with rotation at the c-spine includes:
Brown Sequard, nerve roots
What MOI of SCI c-spine results in dislocation and locking of a single facet joint?
Flexion with rotation
Vertical compression/axial loading of the c-spine occurs most frequently at what spinal cord level, often resulting in?
C4-C5, complete quadriplegia
Most common location in the c-spine for hyperextension MOI is?
C4-C5
True or False: thoracic spine is not usually injured by isolated extension or lateral flexion forces.
True!
What is the result of a flexion-rotation MOI in the lumbar spine?
Highly unstable injury
A flexion-distraction MOI in the lumbar spine is also known as what? What does it typically result from?
Chance fracture
Often result from use of lap belt without shoulder restraint.
What can cause a low-velocity penetrating wound SCI? High velocity?
Low: knife, ice pick, velocity bullets
High: high powered rifles, explosion (does not have to penetrate spine or spinal cord to cause damage to neural damage)
What tools can we use to diagnose a SCI?
C-spine lateral radiograph: rapid and effective at diagnosing with 85% accuracy. Add open mouth and AP radiograph, almost 100% accuracy.
CT: will give valuable information on impingement on neuronal canal as well as bony limits of spinal canal.
Myelography: rarely used alone, may be used in conjunction with CT.
MRI: appropriate imaging technique for visualizing the necessary tissues; however, in acute SCI, other equipment in the surrounding area may limit its use.
Difference between concussion, contusion, and laceration in terms of SCI.
Concussion is jarring of the cord without bleeding.
Contusion results in bleeding.
Laceration: cuts or tears within the spinal cord itself.
What falls under functional, extent of injury, and level of injury for SCI?
Functional: quadriplegia, paraplegia
Extent of injury: complete, incomplete
Level of injury: lowest level in which functional power and sensation remain intact
Overarching difference between complete and incomplete SCI injuries.
Complete: all motor and sensory functions are lost below the level of the injury.
Incomplete: an injury is classified as incomplete if there is any function below the level of the injury. Preservation of some sensory/motor function below the level of the injury.
What does ASIA stand for? What is it used to classify?
American spinal injury association
It is used to classify the extent of the injury
How does ASIA define complete SCI?
No motor or sensory function is preserved in sacral segments S4-S5.
How does ASIA define sensory incomplete SCI?
Sensory but NO motor function is preserved below the neurological level; sensory function extends through segments S4-S5 AND no motor function is preserved more than 3 levels below the motor level on either side of the body.
How does ASIA define motor incomplete (C) SCI?
Motor function is preserved below the neurological level, and more than half of the key muscles below the neurological level of injury have a muscle grade less than 3.
