Letter: Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines on the Evaluation and Treatment of Patients With Thoracolumbar Spine Trauma: Radiological Evaluation

Abstract

the Neurosurgery journal published a systematic analysis of radiological evaluation of thoracolumbar spine trauma. 1 Two of 2278 studies showed that adding a MRI scan in acute thoracolumbar trauma can significantly change the fracture classification or decision-making compared with computed tomography (CT) alone. 2,3 Unfortunately, these 2 studies provided only a level III evidence owing to the small sample size and heterogeneous or nonconsecutive patient population. We have recently published the largest clinical series on the impact of MRI in thoracolumbar fracture classification in 244 neurologically intact patients. 4 We believe that our study provides an update on the prior systematic analysis because it provides a larger sample size, a higher level of evidence (level II), and a more robust methodology, as will be discussed later.MRI is frequently conducted for thoracolumbar fracture (TLF) patients with neurological deficits to assess cord injury, although it does not alter the decision between surgery and conservative treatment. On the other hand, patients with intact neurology undergo MRI to determine the posterior ligamentous complex (PLC) status and differentiate between AO type A and B. Previous research comprised a mixed sample of TLFs with and without neurological deficits. 2,3 The fact that our study focused on patients with intact neurology removed bias may have been a critical strength. In addition, the large sample size and consecutive recruitment led to a well-balanced cohort regarding fracture types and mode of treatment. 5 Previous studies' analyses of the impact of MRI on TLFs' classification were hampered by using nonvalid CT/MRI criteria for PLC injury. 2,3 Previous studies identified PLC injury in MRI as a high-signal intensity despite the evidence indicating that black stripe discontinuity is a more specific criterion for diagnosing PLC damage. 6 To overcome this misclassification bias, we defined PLC injury in MRI as back stripe discontinuity due to supraspinous or ligamentum flavum. 7 We have previously shown that using highsignal intensity may reduce CT sensitivity for PLC injury from 91% to 66%. 7 Similarly, prior research defined PLC damage in CT as any positive CT finding of PLC injury, regardless of the variable or added predictive value of CT findings. We have shown that the following 4 CT findings are independent predictors for PLC injury: spinous process fracture, horizontal laminar fracture, facet diastasis, and interspinous widening >4 mm. 7 We proposed the following definition of PLC status in CT

The Influence of Comminution and Posterior Ligamentous Complex Integrity on Treatment Decision Making in Thoracolumbar Burst Fractures Without Neurologic Deficit?

“…22 However, CT-based PLC criteria (Including M1) require multicenter validation before being widely implemented. 26 The previous results imply that confusion about PLC status on CT images may have overestimated the impact of PLC injury in the decision-making process around TL burst fractures. The practicalities of MRI for TL burst fractures without neurological deficits may be simple; MRI can be conducted non-urgently within days of the injury, ensuring an accurate PLC evaluation 23 Alternatively, standing X-rays may demonstrate kyphosis consistent with a ligamentous injury, or these patients can be closely observed for their pain and early development of kyphosis.…”

“… 22 However, CT-based PLC criteria (Including M1) require multicenter validation before being widely implemented. 26 …”

In Reply: Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines on the Evaluation and Treatment of Patients With Thoracolumbar Spine Trauma: Radiological Evaluation

“…The study by Aly et al 1 is commendable because it adds to the current literature on the topic and also addresses some of the drawbacks of the previous studies. However, there are certain limitations of this study such as retrospective, single-institution design, and lack of external validation.…”

“…We would like to thank the editor for giving us the opportunity to reply to the letter and comments by Dr Aly. 1…”

“…We would like to thank the editor for giving us the opportunity to reply to the letter and comments by Dr Aly. 1 Radiological evaluation of thoracolumbar fractures is important for fracture classification and deciding the treatment plan. However, there is no consensus on the imaging protocol followed for the evaluation of these fractures.…”