Cervical spinal cord injury without bone injuries in an alcohol-intoxicated patient with atlantoaxial osteoarthritis.

Dear Editor,

High-level cervical spinal cord injury (CSI) without bony injuries cannot be easily considered in the initial diagnoses for an acutely alcohol-intoxicated patient with an altered mental status. The authors encountered a relatively rare and diagnostically difficult case of CSI at the C1-C2 level without any bony injury, which was caused by atlantoaxial osteoarthritis in an obtunded, alcohol-intoxicated patient after minor blunt trauma.

An alcohol-intoxicated 56-year-old male presented at our emergency department with an acutely altered mental status. Several hours before the visit he had ingested a considerable quantity of alcohol, and 1 h before, he had fallen while hugging a friend. After the fall, his friend found him unconscious. Due to the manner in which he fell, it was unlikely that his head has been struck. His initial Glasgow Coma Scale score was three and he was completely unresponsive to any stimulus. It was initially suspected that severely alcohol intoxication or non-traumatic brain lesions such as intracranial hemorrhage or acute stroke, as the causes of his neurologic status, head computed tomography and magnetic resonance imaging (MRI) were performed initially, but returned normal findings. Because he became alert after the MRI scan, a reliable neurologic examination was possible. It revealed no sensory perception in the entire C3 dermatome and decreased sensory perception below the C3 level. Motor power was of grade 0-1 at each joint of both upper limbs and of grade 2-3 at each joint of both lower limbs, then CSI was strongly suspected. A cervical spine X-ray revealed no bony abnormality from C1 to C5 [Figure 1]. Cervical spine MRI revealed cord contusion and subligamentous hemorrhage at the C1-C2 level and bony resorption and sclerotic change of the odontoid process of C2, suggesting C1-C2 instability related to osteoarthritis of unknown cause [Figures 2a, b and 3]. Over time, he became alert; his motor power improved spontaneously to grade 2 in both upper limbs and to grade 4 in both lower limbs.

Figure 1

X-ray of the cervical spine, showing no bony abnormality from C1 to C5

Figure 2

(a) T-2 weighted sagittal magnetic resonance image (MRI), showing cord contusion (arrowhead) and (b) T-1 weighted sagittal MRI, showing subligamentous hemorrhage (black arrow) at the C1-C2 level

Figure 3

T-2 weighted axial magnetic resonance image, showing bony resorption and sclerotic change of the odontoid process of C2 (white arrow)

Cervical degeneration is a major cause of CSI without bony injuries. However, in this situation, the C3-4 or C4-5 level is frequently involved and C1-C2 level injuries are relatively rare.[12] Interestingly, in our patient, C1-C2 CSI without bony injury developed due to atlantoaxial osteoarthritis with instability after minor blunt trauma. Degenerative arthritis of the atlantoaxial joint has been discussed only infrequently, but it has been established degeneration of articular cartilage, reduction in joint space and secondary incompetence of ligaments controlling movement can cause atlantoaxial instability.[3] This case emphasizes the importance of considering the possibility of CSI in an obtunded, alcohol-intoxicated patient even when a traumatic event is minor and in the absence of a definite cervical spinal bony injury and C1-C2 CSI without bony injury can develop due to atlantoaxial osteoarthritis after minor blunt trauma.