A patient underwent outpatient knee arthroscopy with spinal anesthesia administered at the patient's request. The patient was discharged after a 3-hour recovery period. Three days later, the patient returned because of a headache that had begun the evening after surgery and progressively worsened. Treatment with caffeine and hydration for presumed postdural puncture headache resulted in relief for approximately 1 hour. An epidural blood patch was then performed and relieved symptoms for 3 hours until backache began and worsened over the next 7 hours. Computed axial tomography showed epidural air. After symptomatic treatment and observation overnight, the patient was released, and follow-up by telephone was planned. For 2 days, symptoms persisted. Therapy with aspirin 600 mg 4 times daily resulted in acute and significant relief. The backache resolved after 1 week. A review of the literature on backache following epidural blood patch is presented.