J Korean Neurosurg Soc.  2011 Mar;49(3):178-181.

Congenital Cleft of Anterior Arch and Partial Aplasia of the Posterior Arch of the C1

• Choi JW
• Jeong JH
• Moon SM
• Hwang HS

Abstract

Congenital anomalies in arches of the atlas are rare, and are usually discovered incidentally. However, a very rare subgroup of patients with unique radiographic features is predisposed to transient quadriparesis after minor cervical or head trauma. A 46-year-old male presented with a 2-month history of tremor and hyperesthesia of the lower extremities after experiencing a minor head trauma. He said that he had been quadriplegic for about 2 weeks after that trauma. Radiographs of his cervical spine revealed bilateral bony defects of the lateral aspects of the posterior arch of C1 and a midline cleft within the anterior arch of the atlas. A magnetic resonance imaging revealed an increased cord signal at the C2 level on the T2-weighted sagittal image. A posterior, suboccipital midline approach for excision of the remnant posterior tubercle was performed. The patient showed significant improvement of his motor and sensory functions. Since major neurologic deficits can be produced by a minor trauma, it is crucial to recognize this anomaly.

Keyword

Congenital anomalies; Cervical atlas; Spinal cord injury; Head trauma

MeSH Terms

Cervical Atlas
Craniocerebral Trauma
Humans
Hyperesthesia
Lower Extremity
Magnetic Resonance Imaging
Male
Middle Aged
Neurologic Manifestations
Quadriplegia
Sensation
Spinal Cord Injuries
Spine
Tremor