Delayed myelopathy caused by cerebrospinal fluid pseudocyst following decompression for thoracic ossification of the ligamentum flavum: a case report and literature review.

backgroundDelayed neurological deterioration caused by a postoperative high-pressure cerebrospinal fluid (CSF) collection is an uncommon but clinically recognized complication after thoracic decompression complicated by incidental durotomy. We report a case of delayed thoracic myelopathy due to a tension subfascial CSF collection and summarize relevant literature. CASE PRESENTATION: A 55-year-old woman with thoracic myelopathy due to ossification of the posterior longitudinal ligament at T2-4 and ossification of the ligamentum flavum at T5-6 underwent posterior decompression and instrumented fusion (T2-6 laminectomy with T1-6 instrumentation). An incidental dural tear occurred at T5-6 and was managed with an onlay artificial dural patch reinforced with fibrin glue and gelatin sponge. The wound drain was removed on postoperative day 7. On postoperative day 9, she developed acute left lower-extremity weakness. MRI demonstrated a large subfascial CSF collection causing significant spinal cord compression, consistent with a tension pseudomeningocele. Bedside subfascial incision and continuous closed low-level drainage (with the drainage bag kept at bed level) resulted in rapid neurological improvement. After recurrence following drain removal, ultrasound-guided drainage was performed, leading to sustained symptom relief. At 3-month follow-up, she had full motor recovery and follow-up MRI confirmed resolution of the collection with adequate decompression.

conclusionsA tension subfascial CSF collection after incidental durotomy can mimic recurrent stenosis and cause delayed thoracic myelopathy. When imaging confirms a compressive CSF collection, continuous closed low-level subfascial drainage may be considered before revision surgery.