Context: Post-traumatic syringomyelia treatment usually focuses on restoring normal cerebrospinal fluid (CSF) flow. Herein, the first-reported case of delayed post-traumatic syringomyelia associated with an L2 compression fracture 30 years prior to syringomyelia symptoms that rapidly progressed to the brainstem within 5 months, leading to respiratory and circulatory impairments, is summarized. The improvement in symptoms and significant decrease in size of the syringomyelia/syringobulbia achieved in this patient suggest that the initial treatment of choice in such acute cases should be posterior fossa decompression (PFD). Intradural exploration in order to restore the normal CSF flow at the level of trauma can then be planned in a later time.Findings: A retrospective analysis of clinical manifestations and findings obtained from magnetic resonance (MR) imaging, including pre-operative and post-operative follow-up data acquired 6 months later, provided adequate comparisons of the neurological deficits and syrinx size. Interestingly, serial MR images showed that a cervical syrinx acutely progressed to the brainstem within 5 months. PFD and sectioning of the thick veil completely obstructing the foramen of Magendie resulted in partial resolution of the neurological deficits and syringomyelia regression after surgery.Conclusions: To our knowledge, this is the first case report to summarize the delayed complications of a spinal cord injury and acute syringomyelia progression to the brainstem in a short period. The symptoms were relieved by an emergency PFD, chosen due to the rapid progression of symptoms. An atypical treatment strategy is described for extremely rare cases, but with a good short-term prognosis.