7. Deutscher Wirbelsäulenkongress, Jahrestagung der Deutschen Wirbelsäulengesellschaft, 6. – 8. Dezember 2012, Stuttgart

Abstract

Introduction: A pseudomeningocele (PMC)is a rare complication after spinal surgery. There is little information about the incidence of this postoperative problem. The literature describes this entity in 0,07-2% of cases. A PMC can appear after intradural operation, inadvertently after extradural surgery, or in case of spinal trauma. Spinal nerve root herniation into such a PMC is a very rare complication and can produce clinical symptoms even years after an operation or a trauma. Material and Methods: Case 1: A 64 year old man described sciatica for L5 on the right side and difficulties in walking for about 3 months. On examination he had a rightsided hypoaesthesia of DI. The CT of the lumbar spine revealed a disc herniation at LW 4/5 level. The patient was treated by operation of the spinal disc herniation. This was completed without any complications and his mobility was restored without pain. 3 months later he had diffuse sciatica again including both limbs. MR imaging (MRI) showed a comprimation of the cauda equina by a dorsal arachnoidal cyst,which was repaired surgically. The patient recovered well. 4 weeks later the patient had deep lumbar pain but on examination no sensomotoric deficit. MRI showed a fluid collection in the area of the operation, consistent with a PMC ( Image 2). Intraoperatively a spinal root herniation next to a small dura suture defect was found and after enlargement of the dura defect, the spinal nerve root was replaced intradurally and the dura was closed with suture. After surgery the pain resolved and the further course of the patient was uneventful. Case 2: A 64 year old woman had non specific back pain with sciatica on both legs intermittendly. The MRI showed an intradural tumor LW1/2, at the conus meduallaris. Through a L2 hemilaminectomie and a midline durotomy the tumor was removed completely. Dura was closed with a non-resorbable running suture and a special glue patch. The operation was completed without any complications and the patient discharged without a neurological deficit and without pain. Histological examination revealed an ependymoma WHO II. The MRI 1 month later showed proper conditions, just a small epidural cerebrospinal fluid (CSF) formation. 4 month later the patient had progressive sciatica. The MRI exhibited a small epidural CSF formation with a conspicuous formation at the dura in the operation area (Image 2). At revision, we found a CSF collection and multiple spinal root nerves extruding through a small dural suture defect. After enlargement the dura defect the spinal root nerves were replaced intradurally and the dura was closed with suture. The patient was discharged without neurological deficit or pain. Results: A PMC or cerebrospinal fluid leakage with herniation of a nerve root or a cauda equina herniation is very rare, but can be a devasting complication of spinal surgery. There are only 10 cases of nerve root entrapment into a PMC or cerebrospinal fluid leakage described in the literature. Clinically, these herniations manifested with pain caused by the entrapped nerve root within an interval from one day up to years after the operation or trauma. It was shown in the literature that from 12 patients (including our cases) 3 patients had a motoric or sensoric deficit, caused by a strangulation of neural tissue in the dura defect. Revision surgery with the replacement of the herniated roots intradurally and resuturing of the dura with or without glue patch is the adequate treatment. Conclusion: From our point of view it is necessary to keep this complication in mind if clinical symptoms correlate with intradural operations or trauma. A special problem is sometimes the long time between operation or trauma and the beginning of the clinical symptoms. MRI is the first step to identify the complication. (Figure Presented) .