A congenital anomaly of the atlas as a diagnostic dilemma: a case report

The purpose of this case report is to draw attention to the differences between a Jefferson fracture and a congenital anomaly of the anterior and/or the posterior arch of the atlas.

A 42-year-old woman visited the chiropractic practice complaining of headache, neck pain, dizziness, and numbness in both of her arms after she fell vertically and directly on her head twice on a playground. Before this fall, she had no such complaints. After taking x-rays of the cervical spine, a Jefferson fracture was suspected.

After computed tomography and magnetic resonance imaging scanning, the patient was diagnosed with a congenital anomaly that looked very similar to a Jefferson fracture. After instability of the cervical spine was excluded by the neurosurgeon, chiropractic treatment was delivered. After 6 treatments, the complaints were significantly reduced.

It is important to be familiar with the differences between a congenital anomaly of the atlas and a Jefferson fracture and to exclude instability of the upper cervical spine before treatment is started.