Occipital condyle fracture and lower cranial nerve palsy after blunt head trauma - a literature review and case report

Abstract

Background: Lower cranial nerve (IX-XII) palsy is a rare condition with numerous causes, usually non-traumatic. In the literature it has been described only a few times after trauma, mostly accompanied by a fracture of the occipital condyle. Although these types of fractures have rarely been reported one could suspect they have been under-diagnosed. During the past decade they have been seen more frequently, most probably due to increased use of CT- and MRI-scanning. The purpose of this review is to increase the awareness of complications following injuries in the craniocervical region.

Methods: We based this article on a retrospective review of the medical record of a 24-year old woman admitted to our trauma center after being involved in a car accident and a review of the literature on occipital condyle fractures associated with lower cranial nerve palsy.

Results: The multitraumatized patient had suffered a dislocated occipital condyle fracture. Months later she was diagnosed with palsy to cranial nerve IX-XII. Literature review shows that occipital condyle fractures are rare as isolated injuries and are in many cases accompanied by further injuries to the cervical spine and soft tissue structures, in many cases ending with severe disability. The exact mechanism leading to these injuries cannot always be explained.

Conclusion: Recognition of soft tissue injuries in patients with blunt head trauma is important. CT findings involving the craniocervical junction in these patients advocates further investigations including a thorough neurological examination and liberal use of MRI.

Keywords: Collet-Sicard-Syndrome; Cranial nerve palsy; Occipital condyle fracture.

Figure 1

Comminute fracture through the occipital condyle on the right side in coronal and axial views.

Figure 2

T2-weighted MRI of the spinal canal in the sagittal plane demonstrates a probable arachnoid cyst located anterior to the spinal cord from C2 and downwards. Additional MRI of the thoracic spine showed extension down to Th10. The MRI was performed one year after the accident.

Figure 3

Left sided atrophy of the trapezius muscle and scapular winging (arrows).

Figure 4

Types of OCF based on the Anderson and Montesano classification system (Types I-III) compared with the Tuli classification system (Types 1, 2A, and 2B), it shows the left craniocervical junction from its medial aspect. The dura and the inferior aspect of the alar ligament have been removed to show the fractured condyles in the fracture types. Tuli S, Tator C.H, Fehlings M.G, Mackay M (1997) Occipital condyle fractures. Neurosurgery;41:368-76.

Figure 5

Demonstrates the suggested injury mechanism; compression (arrow) on the right side causes the occipital condyle fracture and a simultaneous stretching (arrow) on the contralateral side leads to injury of the left sided nerves. Dorsal view. (after Frank H. Netter: Atlas of Human Anatomy 4th ed., plate 11,22).