COMPRESSION OF THE UPPER CERVICAL SPINAL-CORD CAUSING SYMPTOMS OF BRAIN-STEM COMPROMISE - A CASE-REPORT

Study Design. A case is reported in which a flexion-induced compressio n of the upper cervical spinal cord caused symptoms of brainstem compr omise in the absence of radiographic evidence of osseous instability. Objectives. A 41-year-old woman developed postoperative cervical insta bility with flexion-induced neurologic symptoms referable to the brain stem. The instability was caused by direct compression at the third ce rvical vertebral body, which in turn was caused by differential moveme nts between the neuraxis and skeletal elements in the upper cervical s pine. Summary of Background Data. Pathologic processes at the cranioce rvical junction may cause brainstem compromise with neurologic symptom s. The mechanism of brainstem involvement is usually either vertebroba silar insufficiency or direct mechanical compression. in cases where t he brainstem is compressed by skeletal elements, the compressing osseo us structures usually are the walls of the foramen magnum or the odont oid process, or, less frequently, the atlas or axis vertebrae. Symptom s of brainstem dysfunction caused by dynamic compression at the level of the third cervical vertebra in the absence of hindbrain herniation are unusual and, to the best of the authors' knowledge, have not been described previously. Methods. The patient underwent initial examinati on, evaluation, and periodic follow-up examination with magnetic reson ance imaging from the time of her first visit until 26 months after th e surgical treatment. The patient experienced postsurgical instability with dynamic compression by the C3 vertebral body, which caused brain stem compromise. Surgical treatment consisted of decompressive C3 corp ectomy and fusion of C2 to C6, supplemented by anterior fixation. Resu lts. After undergoing surgical decompression of C3, reconstruction, an d anterior internal fixation of C2 to C6, the patient had dramatic neu rologic improvement. Diplopia, paresthesia, and nystagmus disappeared immediately: after: surgery. Swallowing difficulties, hoarseness, and vertigo improved gradually. At follow-up examination 26 months after s urgery, the patient-was: asymptomatic. Magnetic resonance imaging show ed good position Of the construct,: with no evidence of compression of the spinal cord or brainstem. Conclusions. Instability Of the cervica l Spine may result in symptoms of brainstem dysfunction, even in the a bsence of hindbrain herniation. This instability is explained by the d ifferential movement between, the bony structures and neuraxis in the upper cervical region. Diagnosis and adequate management of this insta bility alleviates the neurologic symptoms prevents possible. hazardous complications.