Introduction:
Because the facet joints in younger children are horizontal, pseudo-subluxation of the cervical spine is a physiologic radiography variation of the cervical spine. Estimates place the prevalence of pseudo-subluxation of the cervical spine between 19 and 40 percent in children under the age of eight. On lateral radiographs, this is observed as an apparent anterior misalignment of C2 relative to the C3 vertebral body; if images are obtained with the subject flexed, this may appear more pronounced.
In emergency rooms, neck discomfort from whiplash injuries frequently presents as a presenting symptom. Clinicoradiological examination of the cervical spine is often challenging. One to three cervical spine injuries have a four to eight percent chance of being missed, and a botched or delayed diagnosis could have disastrous consequences. When anterior, posterior, and open-mouth odontoid views are included, the lateral cervical spine radiograph's overall diagnostic sensitivity for skeletal injuries rises to over 100 percent. Ninety-seven percent of the time, the lateral view is diagnostic for non-skeletal injuries.
What Is Pseudosubluxation of the Cervical Spine?
A common anatomical variation known as pseudo-subluxation causes physiological misalignment and anterior slippage of the C2 body on the C3 due to ligamentous laxity. Up to one-fifth of children under sixteen have it, and simple radiographs typically show it. This kind of anterolisthesis is uncommon in adults, but it can be expected if it measures three millimeters. There is no proof that the successful radiological criteria for children can be transferred to the adult cervical spine, nor that they eliminate the need for additional imaging to rule out pathological injury.
From the patient's standpoint, a precise and timely diagnosis ought to result in better care and outcomes and make any upcoming medicolegal concerns easier to handle. Because the facet joints in younger children are horizontal, pseudo-subluxation of the cervical spine is a physiologic radiography variation of the cervical spine. A relative anterior translation of C2 on C3 of up to four millimeters, which resolves with cervical spine extension, is used to diagnose radiographically. Treatment is observation; the disease eventually disappears as the cervical facet joints become more vertical with age.
What Is the Epidemiology of Pseudo-subluxation of the Cervical Spine?
About 20 percent of children who are admitted due to polytrauma will exhibit this unintentional discovery. It has not been shown that there are any correlations with injury severity, trauma, gender, or status of intubation. Children under the age of eight exhibit it. The most common cervical spine pseudo-subluxation is physically placed on C2 on C3. On C4, C3 is the second most typical.
What Is the Etiology of Pseudo-subluxation of the Cervical Spine?
Pathophysiology indicates that the cause at younger ages is the facet joints' horizontal nature.
As we mature, facet joints become more vertical.
How Is Pseudo-subluxation of the Cervical Spin Diagnosed?
The following radiographs are recommended:
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The radiograph shows flexion and extension on the side.
The results of the radiography indicate:
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Reduction of subluxation using X-rays that extend.
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Absence of anterior soft-tissue edema, which is typically associated with trauma.
Radiographs of the cervical spine are quite sensitive; however, they are not always specific. The accuracy of a diagnosis greatly depends on the observer's experience. Prevertebral soft tissue edema can neither be reliably excluded nor predicted based on its presence.
Losing alignment or subluxation between two contiguous vertebrae typically suggests an occult skeletal or non-skeletal injury. Yet, there may also be a hidden bony or ligamentous injury, 9 to 11. It is also possible for there to be a physiological anterolisthesis, or pseudo-subluxation, of C2 on C3, which typically measures little more than 2 mm. While it is prevalent in children5, it has seldom been reported in adults at C2-C3 or C3-C4. It's crucial to differentiate C2-C3 pseudo–subluxation in adults and children from acute spondylolisthesis brought on by a "hangman's fracture," or fracture of the pars interarticularis of C2.
Swischuk established a posterior cervical line between the anterior cortices of the posterior arches of C1 and C3 to aid in diagnosis. He analyzed and compared the radiographs of eight children with traumatic spondylolisthesis and twenty-six children with physiological subluxation. He discovered a significant radiological difference between the two groups. He proposed that a traumatic spondylolisthesis was improbable if the anterior cortex of the posterior arch of C2 was located within 1.5 mm of the posterior cervical line.
It needs to be clarified whether this observation is for adults. Although there was a two-millimeter discrepancy, there was no pars fracture. According to biomechanical research, hyperflexion-related upper cervical spine injuries are more likely to result in ligamentous damage.
Flexion and extension views evaluate the posterior ligament complex's structural integrity. In this instance, flexion views revealed that the spondylolisthesis seemed to resolve in extension and did not appear to worsen. However, it is unclear how useful normal flexion and extension radiographs are when neck pain is in an emergency. The final test in our investigation was a magnetic resonance scan, which is the gold standard for non-skeletal injury screening despite its high cost. One to three cervical spine injuries are often ignored, and inadequate or delayed diagnosis can have disastrous consequences. Even mild cervical spine abnormalities need to be thoroughly assessed.
What Is the Differential Diagnosis?
Actual traumatic subluxation: Reduction of subluxation with neck extension and the spinolaminar line within 1.5 mm of C2 favor pseudo-subluxation rather than actual traumatic subluxation. Neither a history of severe trauma nor any physical evidence of it. Absence of edema of the anterior soft tissues. Hangman's fx may result in true traumatic subluxation.
Conclusion:
Prior knowledge of variances in the child's cervical spine's normalcy is crucial when assessing pediatric patients for cervical spine injuries. For the initial assessment of trauma, a lateral radiography study of the child's cervical spine suffices. To improve the final result, lower costs for extra resources, and spare the child from needless radiation exposure, a multidisciplinary agreement involving radiology, orthopedics, and pediatrics must be established regarding the initial assessment of children with cervical spine trauma.
