10 Most important viewCan see 80-90% of injuriesInterpretation:A - adequacyA - alignmentB - boneC - cartilageD - discS – soft tissueA - Must have a view of C7 – T1A - Use 3 lines1. anterior vertebral line2. posterior vertebral line3. spino laminar line (base of spinous processes)4th line can be used ie. Tips of spinous processes
11 Check :B - individual vertebraeC - cartilageD - discS - soft tissue -<7mm at C3<21mm at C7no more than vertebral body width at C7Predental space –5mm child3mm adultFanning of spinous processes
12 Open mouth viewAdequate if entire Odontoid and lateral borders of C1 and C2 visibleCheck :lateral masses of C1 must align with Odontoidbilateral symmetryImportant also for Odontoid fractures
18 FLEXION TEARDROP FRACTURE UNSTABLEPosterior ligament disruption and anterior compression fracture of the vertebral bodyPrevertebral swellingTear drop fragmentPosterior vertebral body subluxation into the spinal canalSpinal cord compressionFracture of spinous process
19 Mechanism – Hyperflexion and Compression – Excessive flexion of the neck in the sagittal plane, disrupts posterior ligament.Example – diving into shallow pool
21 ANTERIOR SUBLUXATIONDisruption of the posterior ligament complex. Anterior subluxation of C4 on C5 is characterized by widening of the interspinous space (arrowhead), subluxation of the C4-C5 interfacetal joints (arrows), and anterior rotation of the C4 vertebra relative to C5.
22 Stable but potentially unstable during flexion Mechanism : hyperflexionDisruption of posterior ligament complex, anterior intactStable –loss of normal cervical lordosisanterior displacement of bodyfanning of interspinous distanceUnstable –anterior subluxation >4mmassoc. compression fracture >25% of affected bodyincrease or decrease in normal disc space
24 BILATERAL FACET JOINT DISLOCATION Complete anterior dislocation of the vertebral bodyMechanism – extreme hyperflexion of head and neck without axial compressionUnstable – very high risk of cord damageFeatures –complete anterior dislocation >50% of vertebral body diameterDisruption of the posterior ligament complex and anterior longitudinal ligament“Bow tie” appearance of the locked facets.
26 CLAY SHOVELLER’S FRACTURE Fracture of spinous process C6-T1Mechanism – powerful hyperflexion, usually combined with contraction of paraspinous muscles pulling on spinous processes(e.g. shovelling).Features –spinous process fracture on lateral viewGhost sign on AP – double spinous process of C6/C7 due to displaced fractured spinous process
28 UNILATERAL FACET JOINT DISLOCATION StableMechanism – simultaneous flexion and rotationFacet joint dislocation and rupture of the apophyseal joint ligamentsFEATURES :Anterior dislocation of vertebral body by <50% of the diameterDiscordant rotation above and below involved levelFacet within intervertebral foramen on oblique view“Bow tie” appearance of the overriding locked facets
29 EXTENSION INJURIESExcessive extension of the neck in the sagittal plane.E.g. hitting the dash board in MVA
31 HANGMAN’S FRACTURE Fractures through pars interaticularis of the axis Unstable if occurs with facet dislocationMechanism – hyperextensionFeatures –Prevertebral soft tissue swellingAvulsion of anterior inferior corner of C2 assoc. with rupture of the ant. Longitudinal ligamentAnterior dislocation of C2 bodyBilateral C2 pedicle fractures.
36 BURST FRACTURE Fracture of C3-C7 that results from axial compression Spinal cord injury secondary to displacement of posterior fragments is common.Mechanism – Axial compression>25% loss of height of vertebral bodyStableNeeds CT or MRI
39 JEFFERSON FRACTURE Burst type fracture of C1 Lateral displacement of C1 massesFracture of anterior and posterior arches on both sides – quadruple fractureUnstable – transverse ligament ruptureSoft tissue swelling is marked on Xray