All of the following are true about fracture of the atlas veebra, except:
B i.e. Quadriplegia is seen in 80% cases Jafferson fracture is burst fracture of ring of atlas (Cl) veebraeQ. In most cases it doesn't leads to neurological deficitQ. With the exception of pain or loss of sensation in the greater occipital nerve distribution neurological sequelae are uncommon and more likely to be related to associated injuries. It is most common type of atlas fractureQ. It is cause by axial compression forceQ (with or with out extension force), resulting from a fall on the head from a height or mass falling on head. This mechanism of injury results in a burst fracture of ring of atlas (C1) veebraeQ, that occurs secondary to the occipital condyles being driven into the interior poions of the ring of atlas and driving the lateral masses outwards. Lateral displacement of C1 lateral mass lateral the outer coex of the C2 lateral mass raises concerns for the structural integrity of the transverse atlantal ligament (TAL). The stability of atlas depends on TAL. Due to outward movement of lateral masses, there is no encroachment on the neural canal and, usually, no neurological damageQ. Classical Jafferson's fracture (as described by Jafferson in 1920) was four pa fracture of ring of atlasQ (2 pa of anterior ring & 2 pa of posterior ring). However more common are two pa or three pa fractures. It is tyically diagnosed on plain radiographs - pen mouth (odontoid) view may show asymmetry of the lateral masses of C1 on C2 with overhang. - A bilateral overhang > 6.9 mm suggest disruption of transverse ligament and potential late instability. - On lateral radiograph presumptive evidence of transverse ligament disruption is >4mm atlanto-dens interval. Coronal C T reformation provides the best method of evaluating impoant atlas fracture characteristicsQ. The treatment for isolated atlas injuries is typically nonoperative - Undisplaced stable injuries are managed by semi rigid cervical collar or halo- vest until fracture unites. - Unstable injury wit transverse ligament rupture (> 7mm displacement of lateral mass) is managed by halo traction f/b halovest immobilization for a total of 3 - 4 months. - If a late instability or nonunion is present, atlanto - axial (C1 - C2) ahodesis and atlanto - occipital (cervico- occipital) fusionQ. is done Fracture of atlas are associated with injury elsewhere in cervical spine in upto 50% of cases; odontoid fractures and hangman's fractures in paicular should be excluded.
Jefferson fracture is the most common type
Quadriplegia is seen in 80% cases
Atlantooccipital fusion may sometimes be needed
CT scans should be done for diagnosis