Failed back surgery syndrome (FBSS) is a condition characterized by persistent or recurring back pain following spinal surgery. Etiological factors for FBSS are being studied by investigators and clinicians in an attempt to organize them based on their temporal relation to the surgery event. However, many questions regarding the pathophysiology of FBSS remain, which has resulted in a lack of efficacy among its treatment options. In this report, we present a remarkable case of longitudinally extensive transverse myelitis (LETM) in a patient with a medical history of FBSS who was taking multiple pain medications but had persisting pain. The patient, a 56-year-old woman, presented with an incomplete motor injury (American Spinal Injury Association Impairment Scale D) and a neurological level of C4. Investigations revealed an idiopathic LETM that was unresponsive to high doses of corticosteroids. An inpatient rehabilitation program was initiated, resulting in favorable clinical progress. The patient no longer complained of back pain, and her pain medication was gradually discontinued. At the time of discharge, the patient was able to walk with a stick, dress and groom herself independently, and eat with an adapted fork without experiencing pain. As the pain mechanisms underlying FBSS are complex and not yet fully understood, this clinical case aims to contribute to the discussion of possible pathological mechanisms implicated in LETM that may have contributed to the shutdown of pain perception in a patient with a history of FBSS. By doing so, we hope to identify new and effective ways to treat FBSS.