Recurrent multilevel postoperative spinal epidural hematoma in a patient with essential thrombocythemia: failure of repeated decompression and hematological correction. Illustrative case

BACKGROUND: Postoperative spinal epidural hematoma (SEH) is an uncommon but serious complication after lumbar endoscopic surgery, with an incidence of 0.1%-0.2%. Although percutaneous endoscopic lumbar discectomy (PELD) minimizes tissue disruption, SEH may still occur, particularly in patients with hematological disorders. Essential thrombocythemia (ET) presents a hemostatic paradox of simultaneous bleeding tendency and hypercoagulability, increasing postoperative hematoma risk. Massive multilevel SEH after PELD is rare. OBSERVATIONS: A patient developed severe left leg pain immediately after PELD. A second endoscopic reexploration was performed without MRI, removing clotted blood, but symptoms rapidly recurred, prompting open decompression at L2-4. MRI performed afterward revealed a massive posterior epidural hematoma from L1 to S1, similar to previously reported multilevel SEHs. Rapid hematoma reaccumulation was attributed to uncontrolled ET following discontinuation of cytoreductive therapy. Neurological symptoms stabilized only after the resumption of hydroxyurea and anagrelide, with MRI showing near-complete resolution. LESSONS: This case illustrates the hemostatic paradox of ET in spine surgery, in which excessive bleeding and rapid clot formation coexist. When hematological instability drives SEH, repeated decompression may fail, and hematological correction becomes essential. Surgeons should recognize the limitations of endoscopic hemostasis and consider early hematological optimization when postoperative symptoms recur. https://thejns.org/doi/10.3171/CASE25962.