Os odontoideum: case report

André Rodrigues Pinho,Rui Alexandre Peixoto Pinto,Joana Manuel Ferreira Freitas,António Francisco Martingo Serdoura,Nuno Paulo Alegrete Silva,Abel Vitorino Trigo Cabral,Vitorino Veludo Moutinho

doi:10.1590/s1808-18512012000400018

André Rodrigues Pinho, Rui Alexandre Peixoto Pinto + Show 5 more

Open Access

https://doi.org/10.1590/s1808-18512012000400018

Copy DOI

Journal: Coluna/Columna	Publication Date: Dec 1, 2012
Citations: 2	License type: cc-by

Affiliation: Hospital de São João

Abstract

OBJECTIVE: To report the difficulties in managing a case of os odontoideum. METHODS: Female patient, 12 years old who developed a quadiparesis after minor cervical trauma in October 2005. In the emergency department a congenital cervical anomaly was identified. The patient was placed in a Stryker® frame and, few days later, in a halo bracing. After 3 months, an infection around the pins emerged and the halo vest had to be removed. A severe C1-2 instability persisted and a C1-C2 Gallie procedure was attempted. In the following weeks the bone disappeared and another procedure was attempted in June 2006 - C1 laminectomy and occiput-C3 fusion. In the following months the neurological status of the patient improved and a complete mass of occiput-C3 fusion was observed. RESULTS: We choose a posterior cervical arthrodesis of C1-C2 using the Gallie technique. Since the condition was not resolved we performed a second surgery, C1 laminectomy (determined by SAC of 8, 3 mm in MRI) followed by posterior occiput-C3 fusion. In our case, until now, there is no evidence of axial decompensation, but a more prolonged follow-up is needed. CONCLUSIONS: The treatment of os odontoideum has many considerations but the essential that in the presence of instability and neurological deficit a solid fusion is achieved. In case of failure of posterior atlantoaxial wiring, the occiput-C2 or C3 fusion with rods seems to be an excellent option with a high rate of success, avoiding the need for additional support.

Highlights

In 1863, separation of the odontoid process from the body of the axis was described in a postmortem specimen
In 1886, Giacomini coined the term os odontoideum[1,2]
In the following weeks the graft disappeared and a severe C1-C2 instability persisted with the space available for the spinal cord was 10,8 mm in the X-ray and 8,3 in the MRI (Figures 2 and 3)

Summary

Introduction

In 1863, separation of the odontoid process from the body of the axis was described in a postmortem specimen. Based on the position of the dens tip os odontoideum is described as orthotopic or dystopic. A dystopic os odontoideum is present when the dens is in any other position[2,3] ( Figure 1). In the following weeks the graft disappeared and a severe C1-C2 instability persisted with the space available for the spinal cord was 10,8 mm in the X-ray and 8,3 in the MRI (Figures 2 and 3). Another procedure was attempted, in June 2006, that was a C1 laminectomy and fusion Oxccipital-C3 with Vertex System® (Medtronic) five months after the first procedure (Figure 4 e 5). In the one and half year of follow up she gained a good function – with only a functional grade 3 of 5 in intrinsic muscle of the left hand (C7/C8) as residual deficit - and a complete mass fusion Occipital – C3 was visible in July 2007 (Figure 6)

Findings

Discussion

Conclusion