Spine Flashcards
Presentation of central cord syndrome
Motor: weakness of UE with lesser effect on LE
Sensory: varying degrees of disturbance below lesion
Myelopathic findings: sphincter dysfunction (usually urinary retention)
Etiology of central cord syndrome
Usually seen following acute hyperextension injury in an older patient with pre-existing stenosis from bony hypertrophy
May occur +/- cervical fracture or dislocation
Guidelines for acute central cord injuries
- maintain MAP 85-90 mmHg for the 1st week
- early reduction of fracture-dislocation injuries
- surgical decompression (for progressive deterioration- usually decompressive lami +/- fusion)
Etiology of anterior cord syndrome
Cord infarction in the territory supplied by the anterior spinal artery, may also result from anterior cord compression by dislocated bone fragment or traumatic herniated disc
Presentation of anterior cord syndrome
Paraplegia (if higher than C7 then quadriplegia)
Dissociated sensory loss below lesion: loss of pain/temp (spinothalamic) with preserved 2-point discrimination, joint position, deep pressure (posterior columns)
Classic findings of Brown-Sequard syndrome
Ipsilateral findings: motor paralysis, loss of proprioception and vibration
Contralteral findings: loss of pain and temp, preserved light touch (due to redundant ipsilateral and CL paths, anterior spinothalamic tracts)
Classification of atlanto-occipital dislocations
Type 1: anterior dislocation of occiput relative to the atlas
Type 2: longitudinal dislocation (distraction)
Type 3: posterior dislocation of occiput
Grisel syndrome
AA rotatory subluxation secondary to an infection of the head or neck (usually a retropharnyngeal abscess)
Classification of C1 fractures
Type 1: fractures involving a single arch
Type 2: burst fracture (classic Jefferson fracture)
Type 3: lateral mass fractures of the atlas
Definition of Jefferson fracture
Classically a 4 point burst fracture of the C1 ring, with bilateral fractures to the anterior and posterior arches, usually from axial load compression
Guidelines for isolated atlas fractures
If the transverse ligament is intact: cervical immobilization alone
If the transverse ligament is disrupted: either cervical immobilization alone or surgical fixation and fusion
Definition of Hangman’s fracture
Bilateral fracture through the pars interarticularis of C2 with traumatic subluxation of C2 on C3, most often due to hyperextension + axial loading
Guidelines for isolated Hangmans’ fracture
May initially be managed with external immobilizations
Surgical stabilization in the case of: severe angulation of C2 on C3, disruption of C2-3 disc space, or inability to establish or maintain alignment with external immobilization
Most common mechanism of odontoid fractures
Flexion is the most common mechanism of injury, with resultant anterior displacement of C1 on C2 (AA subluxation)
Classification of odontoid fractures
Type 1: avulsion of the attachment of the alar ligament
Type 2: through the base of the neck, the most common dens fracture
Type 2A: similar to type 2 but with large bone chips at the fracture site
Type 3: through body of C2
Clay Shoveler’s Fracture
Avulsion of spinous processes (usually C7)
This fracture is stable.
Mechanism of teardrop fracture
Results from hyperflexion or axial loading at the vertex of the skull with the neck flexed (eliminating the normal cervical lordosis)
Lhermitte sign
Cervical flexion/extension leads to shocklike sensation radiating down spinal axis and into arms/legs
Specific but not sensitive for cervical spinal cord compression and myelopathy
Nerve root injury that produces Trendelenburg gait
Injury to L5 nerve root
Composition of annulus fibrosis
Type 1 collagen that is obliquely oriented, water, and proteoglycans
High collagen/low proteoglycan ratio
Composition of nucleus pulposis
Type 2 collagen, water, and proteoglycans
Low collagen/high proteoglycan ratio
Mechanism of neurogenic shock
Circulatory collapse from loss of sympathetic tone leads to decreased systemic vascular resistance, pooling of blood in extremities, and hypotension
Treatment of neurogenic shock
Swan-Ganz monitoring for careful fluid management
Pressors to treat hypotension
Presentation of spinal shock
Flaccid areflexic paralysis, bradycardia, hypotension, absent bulbocavernosus reflux