Segmentation failure of the posterior elements at the cervical spine and cervicothoracic junction: report of three cases.

PURPOSE: Vertebral segmentation and fusion failures are quite common and often occur as incidental findings. These anatomical variants may be associated with deformity and lead to pain and other neurological signs. They are less frequent in the cervical spine. We report three cases of rare posterior arch segmentation failure at the cervical spine and cervicothoracic junction, with an interesting pattern of laminar arrangement. METHODS: The clinical and radiological findings of three patients with unusual anatomical variants of the posterior elements of the subaxial cervical spine and cervicothoracic junction are reported. RESULTS: We found various association of scoliosis, partial butterfly vertebra, absent pedicle, transverse process and lateral mass anomalies. Interestingly, we report two different and unusual laminar morphologies. CONCLUSION: Congenital morphological disorders may occur at the lower cervical spine and cervicothoracic junction, and they can involve the vertebral body as well as the posterior arch. We reported three cases of uncommon malformations, with a unique Y- and S-shaped laminar pattern.

Magnetic Resonance Myelography in Congenital Absence of the Cervical Pedicle.

Absence of the cervical pedicle is a very rare congenital anomaly, easily misrecognized as a unilateral facet dislocation in a setting of acute trauma or a neoplastic process like a nerve sheath tumor. Although correct diagnosis can be achieved on the cervical radiograph and confirmed by the CT, MRI Myelography is clearly of additional value because shows the specific relationship and orientation of the nerve roots. To the best to our knowledge, this is the first description of MR Myelography findings.

Congenital defect of the posterior arch of cervical spine : report of three cases and review of the current literature.

Abnormalities of the posterior arch, including congenitally absent cervical pedicle and cervical spondylolysis, are rare entities that are usually found incidentally on neck radiographs. It is important to recognize these characteristic radiological features because their radiographic appearance may cause them to be confused with more serious entities such as fractures, locked facets, and tumor-induced bony erosions. Also, it is important to distinguish these abnormalities from similar pathologies to prevent the use of inappropriate treatment. We report the relevant clinical and radiological findings seen in three cases of posterior arch defect after trauma with review of pertinent literature.