A Case of Occipitocervical Fixation for Orthotopic Os Odontoideum in a 2-year-old Child with Progressive Floppy Infant.

Abstract

Floppy infants caused by craniocervical instability in childhood are extremely rare. Furthermore, due to underdeveloped bone structures, treatment for it is extremely difficult. The patient was a 2-year-old boy who was referred at the age of 1 year for psychomotor developmental delay. The cause was unknown, so he was placed under observation. At the age of 2 years, he remained a floppy infant and had not yet acquired motor skills, so he was referred again. Neurologically, he was in a state of progressive motor paralysis of the limbs. Magnetic resonance imaging revealed damage to the medulla oblongata, and he was diagnosed with orthotopic os odontoideum. A C1 laminectomy was performed, with posterior fixation from a C2 translaminar screw to the occipital bone. The progression of the condition has halted, and the patient is currently undergoing rehabilitation. Here, we report the pathological diagnosis, surgical treatment, and orthotopic os odontoideum timing, a condition presenting with progressive craniocervical instability in infants.