INTRODUCTION: Post-traumatic syringomyelia is a complication of traumatic spinal cord injury consisting in the development of a cavity within the spinal cord. Once considered an uncommon complication, its diagnosis has increased due to increased attention and advances in medical technology. Common symptoms of the syrinx are a sensory loss of the dissociated type with pain and temperature loss and the preservation of fine touch and vibratory sensation. Eventually, a deterioration of motor function with muscle wasting may occur. CASE PRESENTATION: We present the case of a 36-year-old woman who sustained a sport accident in 1996, resulting in AIS A, T7 paraplegia. She underwent a magnetic resonance imaging (MRI) examination because of neck and left shoulder pain that resolved after a short anti-inflammatory treatment. The MRI showed a large cavity involving the cord beneath T6 and the medulla. Septations were present at both the spinal cord and medulla levels. With regard to vertebral status, the MRI showed the presence of severe kyphosis at the fracture level together with spinal cord compression. The neurological examination was normal except for the pre-existing paraplegia and of a slight heat and pain sensation deficit in the C8 dermatome. DISCUSSION: We discuss the need of regular follow-up examinations as even large syrines with involvement of the brainstem may be asymptomatic. We also discuss the possible pathogenetic factors including the type of treatment of the vertebral lesion.