Spinal Cord Injury Without Radiographic Abnormality
In some instances, individuals with SCI may not present with any radiographic abnormalities. Although this is considered less common it is still worth noting. Spinal cord injury without radiological abnormality accounts for approximately 10% of SCIs and can be an indication for MRI. The few studies which have found no radiographic abnormalities are presented in Table 2 below.
Author Year; Country |
Methods | Outcome |
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Martinez-Perez et al. (2017); Canada |
Population: Spinal Cord Injury Without Radiographic Abnormality (SCIWORA) (n=48): Mean age=54±18.3yr; Gender: males=40, females=8; Level of injury: C=48; Time since injury: ≤72hr; American Spinal Injury Association (ASIA): A=2, B=5, C=15, D=26. Intervention: Individuals who were admitted to hospital with cervical SCI, received MRI imaging within 72 hr, diagnosed with SCIWORA, and had at least 1 yr of follow-up were included in this retrospective study. MRI was performed using a 1.5T magnet with axial T1-weighted images, T2-weighted images, and gradient echo (GRE); and sagittal T1-weighted images, T2-weighted images, and short TI inversion recovery sequences. Neurological status was assessed using the ASIA impairment scale at baseline and 1-yr follow-up. Neurological improvement was defined as the improvement of at least 1 point on the ASIA Impairment Scale. Outcome Measures: Disk integrity; swelling; intramedullary hematoma; extramedullary hematoma; edema; cervical canal stenosis; lesion length; maximal canal; maximal spinal cord compromise. |
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Ouchida et al. (2016); Japan |
Population: Spinal Cord Injury Without Radiographic Abnormality (SCIWORA) (n=68): Mean age=62(16-93)yr; Gender: males=52, females=16; Level of injury: C=68; Time since injury: ≤4hr; AIS: A=6, B=7, C=24, D=31. Intervention: Individuals diagnosed with SCIWORA were included in this study. T2-weighted sagittal images were acquired using a 1.5T MRI for all individuals. Additionally, individuals underwent a delayed MRI 2 weeks after injury. Outcome measures were assessed at diagnosis and 1-yr follow-up. Outcome Measures: Increased signal intensity (ISI) grade and range; prevertebral hyper-intensity range (PVH); Neurological status: Japanese Orthopaedic Association scoring system (JOA score). |
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Discussion
Only two studies meeting our inclusion criteria examined individuals diagnosed with SCI without radiographic abnormality (Martinez-Perez et al., 2017, Ouchida et al. 2016). Martinez-Perez et al. (2017) assessed individuals who had normal CT scans and did not find any significant associations between physiological outcome and neurological improvement, except for in lesion length as seen on MRI. In this case, shorter lesion length was significantly associated with neurological improvement. Ouchida et al. (2016) found that MRI signal intensity was not significantly associated with the Japanese Orthopaedic Association scoring system, but prevertebral hyper-intensity range was. The first study suggests that an early MRI may pick up traumatic lesions in cases where CT has been negative. These studies also loosely suggest that MRI is less useful as a prognostic indicator of outcome and status in individuals diagnosed with SCI without radiographic abnormality compared to those with SCI who demonstrate radiographic abnormalities.
Conclusions
There is level 5 evidence (from one observational study: Martinez-Perez et al. 2017) that an early MRI may have prognostic value in individuals with SCI without CT evidence of trauma.
There is level 5 evidence (from an observational study: Ouchida et al. 2016) that MRI may not be an effective diagnostic or prognostic indicator of injury in individuals diagnosed with SCI without radiographic abnormality.