1- Upper cervical spine:
A- ATLAS (C1):
* Fracture Jefferson divergent dislocation of the lateral masses. The fracture lines open the ring of the atlas, bilateral divergence of the lateral masses of C1 to C2 para report on the open mouth opposite cliché is pathognomonic. This is the best scanner that displays the fracture and tear of the alar ligament. Consolidation is long is difficult. Usually treated ortho-pédiquement. It results from an axial compression mechanism. It is usually stable.
B- Axis (C2):
* Fracture of the dens: the most common fractures of the cervical spine; elderly (80 years) suffered a fall from the height or young subject (40) by high-energy accident. It can be neglected and discovery at the stage of nonunion. 2/3 of patients do not suffer any damage. Interested in the neck (the base) often; the mechanism associated with axial compression flexion or extension. potentially unstable fracture exposes the medulla medullary complications dislocation. Stable injuries receive orthopedic treatment (thorax brace). Unstable lesion -> surgery.
* Fracture of the post of arc C2: the result of a trauma hyperextended forced the head (hangman’s fracture -> Hangman fracture). It interests the posterior arch (or pedicle isthmus).
* Sprain C1C2: Rare but serious injury, of hyperflexion mechanism (=> rupture of the transverse ligament). C1 C2 switches threatening shear neuraxis. (Unstable ligament injury). The diagnosis is often delayed; Surgical treatment is still
2- Lower cervical spine:
A- Compression injuries:
Meet in traffic accidents or accidents in diving (axial impaction)
* Fracture in tear-drop (23%): bone involvement and disk-ligament compression and flexion-distraction. The anterior inferior corner of the vertebra is detached (in teardrop); but there especially ligament injuries: the horizontal gaps through the interspinous ligament, severing the yellow ligament, capsules joint mass, the posterior longitudinal ligament and disc. Neurological signs are present in 80% of the recoil of the posterior wall. The treatment is surgical
* Settling anterior vertebral body that are stable (wedge fracture3%) and communicative fractures (burst fractures 7%)
B- Lesions in flexion-extension:
Are separated by the growing importance of wounding strength
– Sprain of the cervical spine: it is often the result of a rear impact on a seated subject. The sudden deceleration mechanism behind-initially an extension followed by a sudden flexion of the head -> “whiplash” or whiplash injury.
This mechanism does not cause bone damage, but a simple stretching of ligaments périrachidiens and compression of the disc. The clinical picture is polymorphic: neck pain, headache, dizziness, vomiting, sleep disorders, anxiety (vago-sympathetic reached). Sometimes the origin of the troubles is a herniated disc traumatic.
– Severe sprain: when forced flexion movement is more important, the posterior interspinous ligaments, joint capsules and especially the posterior ligament (mobile spinal segment) may rupture thereby realizing the severe sprain.radiological signs of severe sprain (lateral view): angulation> 10 ° (between the two endplates of the injured disk) anterolisthesis> 3 mm (anterior sliding of the vertebral body), interspinous gap and discovery of more than 50% the lower articular process.
Most often these signs are observed in the accident referred to as muscle contracture (reflex analgesic) holding joint reports. A dynamic shot (earlier voluntary flexion of the head) can help diagnose severe sprain (made the 10th day after the accident). This deformation is normally completely reducible hyperextended but the treatment is necessarily surgical.
– Biarticulaire dislocation: anterior flexion is even more violent. There is a destruction of all disco-ligamentous structures of union between two vertebrae. Radiographically, the overlying vertebral bodies is more than 50% underlying the body; joint apo-less snails of the overlying vertebra move forward upper joint of the underlying vertebra.This lesion is at the origin of the majority complete tetraplegia.
C- Lesions in rotation:
Are responsible for asymmetrical lesions usually on only one of the two articular processes that can be fractured or dislocated. This injury often accompanied by radiculopathy.