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Updated: Jul 3, 2026

A Novel Vertebral Stabilization Method for Producing Contusive Spinal Cord Injury
Published on: January 5, 2015
Accessory bone clasping the C5 spinous process in a case of craniovertebral junction instability
Abhidha Shah1, Snehal Mannurkar1, Pranjali Naukarkar1
1Department of Neurosurgery, Seth G. S. Medical College and K. E. M. Hospital, Mumbai, Maharashtra, India.
None:
We report the case of a 13-year-old male with craniovertebral junction anomaly characterized by Group A basilar invagination and atlantoaxial instability, presenting with progressive neurological deficits. Imaging revealed an unusual accessory bone in continuity with the C5 spinous process, extending inferiorly toward the posterior elements of C6-C7, appearing to "clasp" the spinous process. The possible developmental origin and adaptive biomechanical role of this anomalous bone are discussed. Following atlantoaxial stabilization, the patient showed significant clinical improvement.
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