Status post fall down 3 stairs. Evaluate for instability and ligamentous injury. The incomplete fusion of the anterior arch of C1, C1 retrosomatic cleft, and absence of the right posterior arch of C1 are better depicted on the prior CT. There appears to be mild high T2 signal and swelling of the prevertebral soft tissues at the C1 through C3 levels and a small amount of fluid anterior to the dens. There also appears to be mild high T2 signal in the anterior C1 vertebra. The anterior atlanto-axial ligament appears attenuated inferiorly, but the apical ligament and tectorial membrane appear to be grossly intact. There is no abnormal signal in the spinal cord. The vertebral body heights and disc spaces are preserved. There is no significant spinal canal stenosis. There is mild heterogeneity of the thyroid gland and a nodule along the inferior aspect of the left thyroid lobe that measures up to 10 mm.
1. Suggestion of mild prevertebral edema at the C1 through C3 levels and apparent mild bone marrow edema in C1 and perhaps partial disruption of the anterior atlanto-axial ligament, which features developmental anomalies that are better depicted on the recent CT, but no evidence of spinal cord injury or subluxation. The constellation of findings may be related to acute traumatic injury and/or reactive changes related to the biomechanical alteration associated with the underlying C1 vertebra developmental anomaly. However, assessment for instability is not feasible without flexion and extension images.2. No evidence of cervical spinal cord injury.3. Mild heterogeneity of the thyroid gland and a nodule along the inferior aspect of the left thyroid lobe, which may represent a lymph node or exophytic thyroid lesion. A thyroid ultrasound may be useful for further evaluation.