C2 semisegmented hemivertebra - a rare anomaly presenting with torticollis.

BACKGROUND: Cervical hemivertebrae are extremely rare anomalies which usually present with restriction of neck movements and torticollis in childhood. Hemivertebrae within the craniovertebral junction have only been reported once previously in the literature. We report a case of semisegmented C2 vertebra presenting in a young adult with cervical pain and torticollis with no other associated anomalies.

CASE DESCRIPTION: A 21-year-old lady presented with a history of neck pain for the past 10 days and longstanding torticollis with head tilt to the left. Computed tomographic scan of the cervical spine revealed a semisegmented hemivertebra located laterally between the C1 lateral mass and C2 on the right side which was not associated with any other bony anomalies, scoliosis or atlantoaxial dislocation. Conservative treatment with physical therapy was the chosen therapeutic strategy.

CONCLUSION: Hemivertebrae within the craniovertebral junction are exceedingly rare anomalies which may present with pain and deformity in childhood and are an important cause of congenital torticollis which may be associated with other spinal, craniofacial, cardiac or renal anomalies.