Unilateral radiculopathy away from the puncture site due to adhesive arachnoiditis after spinal anesthesia for an emergent cesarean delivery: a case report

BACKGROUND: Adhesive arachnoiditis has been described as a deteriorating neurological complication after neuraxial blockade; however, few pieces of literatures have reported minor cases that resemble peripheral neuropathy. CASE PRESENTATION: A 29-year-old nulliparous woman underwent an emergent cesarean delivery under spinal anesthesia at the second and third lumbar interspace (L2/3) without any specific concerns. Subsequently, she developed left L5 and sacral first (S1) radiculopathy that persisted for 2 months. Although the neurological findings more likely indicated peripheral neuropathy, magnetic resonance imaging revealed localized adhesive arachnoiditis at the left L5/S1 level. Her symptoms gradually improved and entirely disappeared within 2 months without any particular treatment. CONCLUSION: The neurological symptoms that show a clear tendency to improve spontaneously do not always undergo a detailed workup. Therefore, such minor adhesive arachnoiditis might have occurred more than expected. Imaging such cases might cumulatively further the understanding of its etiology.