Sudden Post-Traumatic Sciatica caused by a
Thoracic Spinal Meningioma
Spinal meningiomas are slow-growing, benign tumors. They are more common in young adults and elderly women. Symptoms can take several years to appear, with localized pain often being the initial sign. Radicular pain can also occur if the tumor compresses nerve roots.
Sudden symptom onset without prior spinal issues is very uncommon in spinal meningiomas. It may be caused by tumor hemorrhage, spinal cord compression due to concurrent trauma, or nerve root and cord entanglement.
After an accidental fall, literature has reported a previously symptom-free 35-year-old woman experienced intense low-back pain radiating to the right sciatic area and weakness in her right leg.
A CT scan showed no abnormalities, but an MRI revealed a tumor on the left side of the spinal canal at the T11 level, displacing the spinal cord downward and to the right. The conus medullaris was unaffected.
The examination of the nervous system revealed diminished strength in the right quadriceps femoris and the flexor and extensor muscles of the right foot. Both knee and ankle reflexes were heightened, and the presence of a positive Babinski sign was observed. Furthermore, there was a slight reduction in sensation (hypoesthesia) in the right leg.
Surgery was carried out to remove an intradural extramedullary meningioma that was attached to the spinal dura’s left postero-lateral surface at the T11-T12 level. The tumor was identified as an atypical (WHO II) meningioma based on histopathological examination.
After surgery, the patient was symptom-free at the last follow-up, five months post-surgery. Physiotherapy resulted in rapid improvement of right leg paresis, enabling autonomous walking with minimal residual ataxia. The low-back and right sciatic pain progressively disappeared. MRI of the thoracic spine showed no residual tumor or cord compression.
Various factors can contribute to the sudden clinical onset of spinal meningiomas. Symptoms may include abrupt back pain or rapidly worsening neurological deficits. While subarachnoid or subdural bleeding is uncommon in these tumors, it is more frequently observed in other types of tumors.
Another uncommon presentation is acute paraparesis resulting from a vertebral compression fracture at the same level as the tumor. Furthermore, sudden clinical symptoms can arise from abnormal movements of the spine that cause nerve stretching.
Patients with a lower conus position and a tethered cord may experience symptoms even with minor trauma, physical exertion, spinal flexion, or during pregnancy.
In cases where the spinal cord is positioned normally and there is no thickening of the filum terminalis, clinical symptoms typically emerge later due to the adaptive properties of cerebrospinal fluid and nearby vascular structures.
Only when the tumor compression exceeds the capacity of these structures does it directly impact the spinal cord, resulting in neurological deficits. Stretching of the cord and nerve roots is a rare occurrence, usually seen in specific circumstances involving significant spinal trauma.
In the reported incident, the patient’s accidental fall transmitted force to the spine, causing the stretching of the lower spinal cord and displaced lumbosacral nerve roots already affected by the tumor.
The presence of dentate ligaments, responsible for stabilizing the spinal cord within the dural sac, likely contributed to limiting the mobility of the nervous structures and rendering them more vulnerable to stretching after the trauma.
When sciatic pain occurs suddenly after trauma, it is commonly associated with lumbar or peripheral issues. However, if an MRI of the lumbar spine shows no abnormalities and there are objective neurological signs of spinal cord compression, a compression in the low thoracic cord should be considered.