In patients with os odontoideum, there are 2 main forms of management, as follows:
Clinical and radiological surveillance
Operative stabilization
Observation is appropriate in most incidentally diagnosed os odontoideum patients, particularly those without radiographic evidence of significant instability. For patients with mechanical symptoms, medical management is indicated. This treatment includes cervical traction, physical therapy, occasional collar use, and anti-inflammatory medications. Activity limitation often is recommended but is difficult to enforce in the pediatric age group.
Surgical stabilization may be recommended in the following 3 settings:
Spinal instability
Neurologic involvement
Intractable pain
In this setting, spinal instability is defined as cord compression or excessive motion noted radiographically. In the absence of large-cohort, prospective data, radiographic parameters can only be marginally associated with progressive neurologic dysfunction. That said, most authors agree that the following changes on flexion-extension plain lateral cervical radiographs serve as reasonable guidelines for surgery:
PADI less than 13 mm
Sagittal plane rotational angle more than 20°
Instability index more than 40%
C1-C2 translation more than 5 mm