Be aware of the tuft of hair: traumatic lumbar intradural hematoma following spinal anesthesia in a case of occult spinal dysraphism. Illustrative case

BACKGROUND: Spinal intradural hematoma is a rare but potentially devastating complication of spinal anesthesia. Known risk factors include anticoagulation, coagulopathies, spinal trauma, tumors, infections, and congenital spinal anomalies. OBSERVATIONS: The authors report the case of a 27-year-old postpartum female who developed acute bilateral lower limb weakness 3 days post-cesarean section under spinal anesthesia. On examination, she had a tuft of hair in the midline of the low back. MRI of the whole spine revealed a lumbosacral intradural hematoma with incidental findings of spinal dysraphism-diastematomyelia and tethering of the spinal cord. Emergency surgical evacuation was performed, but the patient was left with persistent neurological deficits. LESSONS: This case underscores the importance of maintaining a high index of suspicion and performing a thorough preanesthetic spinal evaluation when cutaneous stigmata suggestive of occult spinal dysraphism are present. https://thejns.org/doi/10.3171/CASE26343.