Delayed postoperative spinal epidural hematomas.

Background Context: Symptomatic epidural hematomas after spinal surgery are uncommon and are usually diagnosed within 24 hours after surgery.

Purpose: We report a series of delayed epidural hematomas in a subset of patients who awoke from surgery neurologically unchanged and then deteriorated more than 3 days after their index procedure. The goals of this report are to outline the clinical presentation, radiological characteristics and outcome of this uncommon entity.

Study Design/setting: We retrospectively reviewed the database of six spine surgeons over a 4-year period, looking for presence of epidural hematomas as a cause of clinical deterioration after an asymptomatic postoperative period of at least 3 days.

Patient Sample: We identified a subset of patients who awoke from surgery neurologically unchanged and then deteriorated more than 3 days after spinal surgery. A total of 4,018 patients were identified over the 4-year period of review.

Outcome Measures: Presence of spinal epidural hematoma as a cause of clinical deterioration after an asymptomatic period of at least 3 days. The medical records, including the history, physical, preoperative and postoperative neurological examinations, as well as plain radiographs and magnetic resonance images, were reviewed.

Methods: We retrospectively reviewed the database of six spine surgeons over a 4-year period. We looked for delayed spinal epidural hematomas as a cause of clinical deterioration after an asymptomatic postoperative period of at least 3 days. We examined potential risk factors for spinal extradural hematomas.

Results: Of 4,018 patients, we identified seven with spinal epidural hematoma who presented more than 3 days after their index procedure. The initial presenting symptom, which heralded the subsequent onset of neurological deterioration, consisted of severe sharp pain with radiation to the extremities. The average time to neurological deterioration was 5.3 days. Fifty-seven percent of the patients had multiple previous spinal surgeries at the site of the epidural hematoma. Surgical evacuation of the epidural hematomas resulted in neurological improvement in five patients. Persistent neurological deficits were observed in two patients.

Conclusion: Delayed spinal epidural hematomas are an uncommon cause of delayed deterioration after spinal surgery. Previous surgery with attendant scarring that results in impairment of clot resorption may be a contributing factor in the development of the condition.