1021 - Persistent Gait Ataxia Without Back Pain or Alarm Symptoms? Consider Thoracic Myelopathy

Case Diagnosis: 58-year old female with persistent gait abnormality 9 months after acute back injury found to have thoracic myelopathy.

Case Description: Patient presented to her PCP with lumbar back pain after lifting a couch 1 month where she endorsed persistent low back pain and difficulty walking. MRI lumbar spine showed epidural lipomatosis and bilateral L5/S1 neural foraminal stenosis. She was prescribed Medrol dose pack, cyclobenzaprine, and physical therapy. After 12 weeks of therapy, back pain resolved but continued difficulty with ambulation now requiring assistive devices. She presented to outpatient Spine Clinic with minimal back pain, denied radicular lower extremity symptoms and red flag signs. Exam notable for mild right greater than left distal lower extremity weakness, 3+ patellar reflexes bilaterally and ataxic gait. MRI cervical and thoracic spine were obtained given persistent deficits and showed large right paracentral disc herniation at T10/11 with associated cord signal changes consistent with thoracic compressive myelopathy. Ultimately, referred to neurosurgery for urgent spinal decompression.

Discussions: Persistent myelopathy can result in permanent spinal cord injury if not addressed appropriately. Many clinicians expect myelopathy to present with extremity weakness, upper motor neuron signs, neuropathic pain, sensory changes, or incontinence. However, one of the most telling symptoms is gait ataxia. Even when myelopathy is considered, the thoracic spine is often overlooked in favor of lumbar and cervical spine as a possible site of pathology. This case underscores the importance of pursuing further evaluation in patients who report resolution of acute lower back pain without accompanying improvement in functional deficits following conservative management.

Conclusions: Consider thoracic myelopathy as a possible diagnosis in patients with persistent gait abnormality and/or decreased balance/coordination in the setting of acute back injury. Even in absence of traditional signs of cord compression, like incontinence, upper motor neuron signs, and extremity weakness on exam.