- See:
- Central Cord Syndrome:
- Extension Teardrop Fracture of C2
- Hangman's frx
- Jefferson Fracture
- Lower Cervical Burst Fractures
- Hyperextension fracture dislocation
- Prevertebral Soft Tissues
- Discussion:
- hyperextension injuries may include:
- hyperextension sprain;
- Hyperextension dislocation;
- traumatic spondylolisthesis (Hangman's frx of C2);
- avulsion injury of the Atlas or Axis;
- isolated laminar fractures;
- may occur from a blow to the face (& accompanied w/ fascial frx)
- mechanism involves distractive anterior forces and compressive Posterior column forces;
- pts w/ severe Spondylosis may suffer neurologic deficit w/ no radiographic fractures or subluxations;
- cord is pinched between posteriorly projecting osteophytes & thickened, bulging ligamentum flavum;
- C2 Laminar Frx:
- isolated laminar frx of Axis have also been described & may be confused w/ traumatic spondylolisthesis;
- laminar frx occurs posterior to the pars interarticularis, & unlike Hangman's frx, is considered a stable injury;
- because of diffus sclerosis in pts w/ Spondylosis, laminar frx may be difficult to detect on plain films;
- while they are stable, fragments may compromise canal & impinge on cervical cord resulting in deficits;
- injuries resulting in anterolisthesis include:
- unilateral facet subluxation (shows > 3-6 mm of anterior offset)
- hyperflexion strain - results in less offset;
- Radiographs:
- unilateral articular mass frx are seen on AP film as disruption of undulating lataeral margin;
- lateral film:
- oblique film:
- prevertebral soft tissue swelling;
- widening of intervertebral disc space;
- fractures of the posterior elements;
- Treatment:
- pts with cord or nerve root dysfunction due to hyper-extension injuries are managed non surgically with an orthosis, & their neurologic
status is carefully monitored