Discoligamentous injuries are severe spinal injuries in which the intervertebral disc and the intervertebral ligamentous structures are involved. They include cervical, thoracic or lumbar anterior tension band injuries as well as translational injuries.
On this page:
Terminology
The term transdiscal fracture is more often used in the setting of a rigid spine and then might be also called chalk or carrot stick fracture.
Epidemiology
Risk factors
Any activity or behavior that might pose a risk for high-impact trauma can be seen as a predisposing factor for a discoligamentous injury. A few clinical conditions that can be considered as risk factors include 1:
rigid spine including surgically fused spine
Associations
Discoligamentous injuries can be associated with the following 2,3:
prevertebral hematoma
concomitant spinal fractures
Diagnosis
The diagnosis is primarily based on imaging features in a setting of a trauma history. Discoligamentous injuries are more readily identified on MRI than on CT or X-ray, a fair amount might be missed on imaging studies, though 2.
Unexplained neurologic deficits after a trauma in the setting of absent bony abnormalities should raise the suspicion of a discoligamentous injury and the acquisition of an MRI.
Clinical presentation
Discoligamentous injuries are usually associated with traumatic events such as a high-impact trauma e.g. motor vehicle accident 2. However, they can also occur within the scope of low-impact traumas e.g. a fall especially if risk factors are present such as a rigid spine 1.
Complications
If untreated discoligamentous injuries might lead to the following conditions 2:
spinal instability and deformity
nerve root compression
Pathology
Discoligamentous injuries are characterized by a traumatic injury or tear of the intervertebral disc and an associated ligamentous injury. This classically includes the anterior tension band in the setting of a hyperextension injury and less often the posterior ligamentous complex and posterior longitudinal ligament in a hyperflexion injury. In the setting of a translational injury, both the anterior and posterior tension bands will be involved 2-5.
Location
Disco-ligamentous injuries can occur in any part of the spine but are more common in the cervical spine and the thoracolumbar junction 1.
Subtypes
The following injuries can be discoligamentous injuries 4,5:
anterior tension band injuries (AO type B3 injuries)
posterior tension band injuries (AO type B2 injuries)
translational injury (AO type C injuries)
Radiographic features
Plain radiograph
Radiographic features which might indicate a discoligamentous injury include the following:
widening of the intervertebral disc space
vertebral malalignment and step-off phenomena with disruption of either the anterior, posterior vertebral, spinolaminar or posterior spinous lines
widening of the interspinous space
CT
In addition to the vertebral malalignment and widening of the intervertebral and posterior interspinous space CT might demonstrate associated subtle bony fractures and/or avulsions as well as paravertebral hematoma or complications as epidural hematoma 2.
MRI
MRI allows better evaluation of the disc and soft tissue structures than CT and can show disruption or tears to the anterior longitudinal ligament, the posterior longitudinal ligament and/or the posterior ligamentous complex as well as disruption, tearing or herniation to the intervertebral disc. It can also show associated findings as e.g. prevertebral hematoma which might indicate the diagnosis or complications such as epidural hematoma 1. These features are usually best demonstrated in the sagittal plane on STIR or fat-saturated T2 weighted images 2,3.
Signal characteristics
T1: intermediate signal intensity
T2: hyperintense
STIR/T2FS: hyperintense
Radiology report
The radiological report should ideally include a classification of the injury and a description of the following features 2-5:
-
type and extent of the injury including the following structures
fractures and bony avulsions
-
associated injuries
prevertebral hematoma
Treatment and prognosis
Discoligamentous injuries usually require surgical management, especially those that are displaced (AO type C) as well as thoracolumbar hyperextension injuries (AO type B3) or in cases where neurological symptoms or a rigid spine is present 1.
Differential diagnosis
Conditions that might mimic the imaging appearance of discoligamentous injuries include:
Unable to process the form. Check for errors and try again.