Os odontoideum: rare cervical lesion.

Area of Science:

• Orthopedics
• Neurosurgery
• Sports Medicine

Background:

• Transient neurological deficits after physical exertion can indicate underlying spinal abnormalities.
• Os odontoideum is a rare congenital or acquired condition affecting the axis vertebra.
• Atlanto-axial instability presents a risk of spinal cord injury.

Purpose of the Study:

• To report a rare case of os odontoideum and atlanto-axial instability in a young active-duty military member.
• To highlight the diagnostic process and implications of this condition for military personnel.
• To emphasize the importance of surgical management for career preservation.

Main Methods:

• Case report of a 22-year-old Marine presenting with extremity weakness and numbness.
• Diagnostic imaging including computed tomography (CT) of the cervical spine.
• Dynamic lateral flexion-extension radiography to assess atlanto-axial joint stability.

Main Results:

• CT revealed os odontoideum, a malformation of the odontoid process.
• Flexion-extension radiographs confirmed significant atlanto-axial instability.
• The patient experienced transient neurological symptoms attributed to the instability.

Conclusions:

• Os odontoideum with atlanto-axial instability is a rare but serious condition.
• Prompt diagnosis and surgical fusion are crucial for preventing catastrophic neurological injury.
• This condition can have career-ending implications for military members if untreated.