Cervical Intervertebral Foramen Research Articles

Quantitative Analysis of Changes in Cervical Intervertebral Foramen Size With Vertebral Translation

Simulated translation of the C5 vertebra was performed in 20 embalmed cadaveric cervical spines, and cross-sectional areas of the C4-C5 and C5-C6 intervertebral foramina were measured and compared before and after translation of the C5 vertebra. To determine the relationship of cross-sectional intervertebral foraminal areas to the degrees of vertebral translation. The common feature of clinical instability and adjacent diseases of the cervical spine is malalignment of the cervical spine (i.e., there is ventral and dorsal translation of vertebral body with respect to the adjacent upper and lower vertebral body, respectively). To our knowledge, no previous study has analyzed the quantitative effect of vertebral translation on the size of the intervertebral foramina. The cross-sectional areas of the intervertebral foramina at C4-C5 and C5-C6 were measured on computerized tomography. The images were then transferred to the personal computer, where consecutive dorsal translations of C5 vertebrae with a 1-mm increment from 1 to 5-mm displacements were performed using Microsoft paint software (Microsoft, Corp., Redmond, WA). National Institutes of Health (Bethesda, MD) Image J software (V1.33m) was then used to measure the areas of both sides of C4-C5 and C4-C6 foramina at normal and each displacement level in the computer. Following dorsal translation of C5 vertebra, anterolisthesis of C4 relative to C5 and retrolisthesis of C5 relative to C6 was noted. No significant difference was found between the measured values using Aquarius Image software (Microsoft, Corp.) on computerized tomography and National Institutes of Health image J software on the desktop computer (P > 0.05). When compared with normal values, there was an increase in the C4-C5 intervertebral foraminal area (i.e., 6%, 14%, 18%, 21%, and 26% with anterolisthesis of C4 relative to C5 following 1, 2, 3, 4, and 5-mm dorsal translation of the C5 vertebra, respectively). There was a 12% decrease in the C5-C6 intervertebral foraminal area, with each 1-mm incremental retrolisthesis of C5 relative to C6 vertebra. Statistically significant differences were found among residual cross-sectional foraminal areas following different degrees of dorsal translation (P < 0.05). There is a significant increase in size with anterolisthesis and decrease in size with retrolisthesis of upper and lower adjacent vertebral intervertebral foramina, respectively.

The Quantitative Anatomy of the Cervical Nerve Root Groove and the Intervertebral Foramen

The present study evaluated the cervical nerve groove and intervertebral foramen using dried vertebrae and cadaveric cervical spine. To measure the cervical nerve groove in eight linear and one angular dimensions and the intervertebral foramen in two linear diameters. Several anatomic studies of the cervical spine exist, but very little quantitative data have been reported on the cervical nerve groove. Dried cervical vertebrae, C3-C7, from 41 complete vertebral sets (205 vertebrae) and 14 cadaveric cervical spine were obtained for the present study. Anatomic evaluation focused on the cervical nerve groove for dry specimens and intervertebral foramen for cadaveric specimens. Ten linear and one angular measurements were made bilaterally. The mean, range, and standard deviation were calculated for all of the specimens and for male and female specimens separately. Differences in dimensions of male and female specimens were not found to be statistically significant. The average lengths of the medial zone and distances from the midline of the vertebral body to the anterior border of the medial zone for male and female specimens consistently increased from C3 to C7. The width of the medial zone was larger in C3 than that of C4, C5, and C6 in male and female specimens. The minimum width for all levels ranged 1-2 mm. The medial zone depths gradually increased from C3 (3.2 mm for male and 2.3 mm for female specimens) to C7 (4.9 mm for male and 4.4 mm for female specimens). The smallest anteroposterior distances from the posterior midpoint of the lateral mass to the posterior border of the nerve groove were found in C7 (6.7 mm for male and 6.1 mm for female specimens). The general trend of the foraminal height and width increased from the cephalad to caudal except at C2-C3. These data may enhance understanding of the important bony elements associated with the cervical spinal nerves and roots as they pass through the cervical nerve groove and the intervertebral foramen.

SMITH-PETERSEN VITALLIUM MOULD ARTHROPLASTY: A 45-YEAR FOLLOW-UP

THE JOURNAL OF BONE AND JOINT SURGERY tions, including 24-hour ambulant monitoring, revealed only atrial fibrillation. Radiographs of the cervical spine showed spondylolisthesis at the C5 to C6 level. Anterior cervical interbody fusion was performed at this level; the bony changes seen at operation were similar to those described in case 1. He had no more drop attacks during the last year of his life. Discussion. We describe two elderly men who had drop attacks and cervical spine instability. In both cases the attacks ceased after limited fusion of the cervical spine. We cannot prove that compression of the vertebral artery was the cause, but this seems likely because of the good results of fusion. Any fracture or dislocation of the cervical spine above the sixth cervical intervertebral foramen may compromise the vertebral arteries, and relative vascular insufficiency may occur in the basilar artery and its branches as well as in the anterior cervical artery. Both our patients were elderly which may explain why the collateral circulation, from the circle of Willis, was not sufficient to compensate for the diminished flow in the vertebral arteries when flexion of the cervical spine led to subluxation. In elderly subjects with unexplained drop attacks instability of a degenerate cervical spine should be considered since surgery may prevent these symptoms.

Primary Spinal Chondrosarcoma Localized in the Cervical Spinal Canal and Intervertebral Foramen

A 48-year-old male presented with a very rare case of spinal chondrosarcoma localized in the cervical spinal canal and intervertebral foramen, but without marked destruction of the vertebral column. Spinal chondrosarcoma is characterized by radiological evidence of destruction of the surrounding bone structure and mottled calcification. Magnetic resonance imaging was useful in the diagnosis and determination of the extent of this spinal chondrosarcoma. However, preoperative differential diagnosis of the tumor was not possible based on neuroimaging evidence.

Cervical intervertebral foramen narrowing and myelographic nerve root sleeve deformities.

Intervertebral foramen narrowing on plain radiographs of the cervical spine was graded from 0 (normal) to 3 according to its severity; myelographic nerve root sleeve deformity was graded from 1 to 3 in 99 consecutive patients with cervical radiculopathy. We thus examined 1118 foramina and root sleeves. Plain radiographs of 684 foramina were normal, changes of one grade were seen in 243, of two grades in 145 and of three grades in 46. Grading of myelographic root sleeves' was normal in 789, changes of one grade in 157, of two grades in 129, and of three grades in 43. The correlations between the foraminal and root sleeve changes were: full correlation in 63.9%, a difference of one grade in 27.4%, a difference of two grades in 7.4% and a difference of three grades in 1.3%. The positive predictive value of the plain radiographs for myelographic root sleeve deformities was 55.5% and the negative value 87.1%.

An unusual presentation of thyroid papillary carcinoma: Enlargement of a cervical intervertebral foramen

Isolated enlargement of the cervical intervertebral foramen is frequently associated with dumbbell neurogenic tumors. We present an unusual case of isolated enlargement of a cervical intervertebral foramen in a 77-year-old male with an aggressive papillary thyroid carcinoma. To our knowledge, this represents the first case describing a thyroid process as a cause of foraminal enlargement.

The myelographic examination of the foramen magnum.

The clinical diagnosis of benign tumors in the region of the foramen magnum is often extremely difficult (2, 5, 8). Even if such a lesion is suspected, a satisfactory diagnosis may not be possible without roentgenologic evidence. In the presence of extradural malignant lesions, bone changes are generally detectable. The benign intradural tumors usually show no alterations on regular x-ray films, though a small proportion may exhibit thinning of one side of the arch of the atlas or ballooning of a cervical intervertebral foramen. Since these lesions may produce severe neurologic damage before complete spinal block appears, an accurate and safe method of confirming the diagnosis at an early stage has been a primary need. This appears to have been met by the development of the myelographic technic. Myelographic examination of the foramen magnum presents some special difficulties as well as special requirements. In this region lesions are easily missed; yet even minor changes can be readily appreciated with a...