Introduction: Subacute posttraumatic ascending myelopathy (SPAM) is a rare event that occurs after spinal cord trauma or ischemia. Here, we review all reported cases of SPAM and discuss the possible pathological mechanisms of this rare condition. We also present an unusual case of SPAM after a gunshot wound to the spine.

Methods: We summarize the full body of available literature on SPAM published in English. We show the initial level and severity of all initial injuries, and describe the progression and recovery demonstrated in each case. We also describe a case of SPAM treated by the authors that illustrates several common and uncommon aspects of SPAM.

Results: The English literature contains 27 descriptions of SPAM, most of which presented with complete SCI. The time from injury to deterioration varied from 2 to 86 days and several patients exhibited spontaneous recovery. In our case, an 18-year-old male presented after a gunshot wound to the neck. He sustained a fracture to C4 and MRI showed subtle T2 changes within the spinal cord centered at C4/5. He was free from long track signs from time of admission to discharge 2 weeks later. Seven weeks later, he developed progressive severe myelopathy and weakness. MRI performed at that time revealed T2 signal change from C2 to C6 without evidence of syrinx or spinal cord compression. His myelopathy spontaneously improved over several weeks.

Conclusions: The pathologic causes of SPAM are unknown, but several hypotheses have been put forth: anterior spinal artery thrombosis, delayed secondary injury, an autoimmune phenomenon or disruption of normal CSF flow. Clinicians must be vigilant in the days and weeks after SCI, and patients should be counseled appropriately, so that SPAM is properly recognized and treatment trials can be carried out.

Patient Care: Educate clinicians on the presentation and pathophysiology of SPAM so that it may be better recognized and treatment trials carried out.

Learning Objectives: - Understand the presentation and clinical course of SPAM - Explain possible pathophysiologic mechanisms of SPAM

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