Neurosurgery

(Fig. 22.2). Cervical traction is contraindicated in this type of injury pattern.

The Powers ratio, which is obtained by measuring the distance between the tip of the clivus (basion) and the posterior arch of the atlas and then dividing this measure by the distance between the posterior margin of the foramen magnum to the anterior arch of the atlas, yields

Fig. 22.2. AOD can be detected by using the Powers ratio. This ratio is obtained by measuring the distance between the tip of the clivus (basion) (Ba) and the posterior arch of the atlas (Clp) This measure is divided by the distance between the posterior margin of the foramen magnum or opisthion (Op) to the anterior arch of the atlas (Cla), and yields a number which is normally 0.7+/- 0.09 in the majority of the population. A value greater than 1 suggests AOD. Plain lateral radiographs will also show an increased distance between the clivus and the tip of the dens. Displacement of the skull relative to the spine either anteriorly (type I AOD) or posteriorly (type III AOD) can also be seen. Type II AOD consists of a longitudinal distraction separating the occiput from the atlas.

Fig. 22.2. AOD can be detected by using the Powers ratio. This ratio is obtained by measuring the distance between the tip of the clivus (basion) (Ba) and the posterior arch of the atlas (Clp) This measure is divided by the distance between the posterior margin of the foramen magnum or opisthion (Op) to the anterior arch of the atlas (Cla), and yields a number which is normally 0.7+/- 0.09 in the majority of the population. A value greater than 1 suggests AOD. Plain lateral radiographs will also show an increased distance between the clivus and the tip of the dens. Displacement of the skull relative to the spine either anteriorly (type I AOD) or posteriorly (type III AOD) can also be seen. Type II AOD consists of a longitudinal distraction separating the occiput from the atlas.

a number which is normally 0.7+/- 0.09 in the majority of the population. A value greater than

1 suggests AOD.

MRI is not only a valuable tool in assessing alignment, but also in detecting ligamentous disruption. Increased signal intensity in and around the ligaments supports the possibility of ligament damage.

Type I and III AOD injuries might benefit from the use of cervical traction to realign the bony structures and to relieve compression of the spinal canal, especially in cases in which there is a neurological deficit, as reversal of these deficits has been documented with 5 lb or less of traction. Once realignment has occurred, patients can then be placed in a halo vest while they await surgical stabilization using internal fixation.

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Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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