The incidence and risk factors of postoperative neurological deterioration after posterior decompression with or without instrumented fusion for thoracic myelopathy

Abstract

The aim of this study was to explore the incidence and risk factors of postoperative neurological deterioration after posterior decompression with or without instrumented fusion for thoracic myelopathy, and hope to provide references in decision-making and surgical planning for both spinal surgeon and thoracic stenosis patients.By retrieving the medical records from January 2001 to November 2015, 168 patients were retrospectively reviewed. According to the occurrence of postoperative neurological deterioration, patients were divided into 2 groups: neurological deterioration (ND) group and non-ND group. To investigate risk values for the occurrence of ND, 3 categorized factors were analyzed statistically: patient characteristics—preoperative data of age, sex, body mass index, bone mineral density, the duration of disease (from first symptoms to operation), the preoperative neurological function (Frankel grade), and diagnosis; surgical variables—surgery time, the amount of bleeding, mean arterial pressure, intervertebral fusion or not, and instrumentation or not; radiographic parameters—the spinal canal occupancy ratio, location of the lesion, thoracic kyphosis, and kyphosis correction.Postoperative neurological deterioration was developed in 23 of 168 patients (13.7%), and were enrolled as ND group. There was no statistically significant difference between the 2 groups in age at operation, sex composition, body mass index, and bone mineral density. The preoperative diagnosis presented significant difference between the 2 groups, because ossification of posterior longitudinal ligament combined with ossification of the ligamentum flavum was more common in ND group, whereas ossification of the ligamentum flavum alone was more common in non-ND group. There was no difference between the 2 groups in mean surgery time, the incidence of intraoperative direct trauma, and the number of patients that received instrumentation. The mean bleeding was much more in ND group than that in non-ND group, and the mean arterial pressure was lower in ND group than that in non-ND group. Also, the mean spinal canal occupancy ratio was more severe in ND group than that in non-ND group. There were no statistically significant difference between the 2 groups in stenosis location and preoperative thoracic kyphosis. The mean kyphosis correction was more significant in ND group. When included in a multivariate logistic regression model, thoracic disc herniation + ossification of posterior longitudinal ligament, spinal canal occupancy ratio more than 70%, bleeding more than 800 mL, and mean arterial pressure less than 81 mm Hg were independently associated with the postoperative neurological deterioration.In conclusion, ossification of posterior longitudinal ligament combined with ossification of the ligamentum flavum, spinal canal occupancy ratio more than 70%, intraoperative bleeding more than 800 mL, and mean arterial pressure less than 81 mm Hg are risk factors for the occurrence of postoperative neurologic deterioration. Improving s...

Clinical effect analysis of laminectomy alone and laminectomy with instrumentation in the treatment of TOLF: a multicentre retrospective study

“…In patients with severe ossi ed ligamentum avum, the spinal cord was fragile, and minor traction or vibrations during intraoperative removal of the ligamentum avum might lead to severe paralysis. In addition, intraoperative instability caused by extensive laminectomy and an increase in kyphosis after laminectomy had been considered as potential causes for postoperative neurological deterioration (however, there were no cases of kyphosis during the follow-up period of this study) [23]. Last but not least, it has been reported that application of instrumentation after laminectomy dose good to postoperative recovery of the injured spinal cord due to thoracic myelopathy, and prevents re-extension of OLF [24][25].…”

A systematic review of surgical procedures on thoracic myelopathy

“…To decrease the incidence of complications, some surgeons suggested a technique that we should keep a floating fragment adherent to the dura matter [26], but the kind of decompression was not satisfactory when compared with a complete decompression. There was another strategy that increasing the mean arterial pressure could prevent the neurologic deterioration, because Wang et al found that mean arterial pressure less than 81 mmHg was one of risk factors [7]. Besides, to release the immediately neurologic deterioration, glucocorticoid was suggested to ease the inflammation after surgery.…”

“…Ultimately, 35 studies met the inclusion criteria by reviewing the full-text articles ( Fig. 1) which contained 5 retrospective comparative studies [6][7][8][9][10] and 30 case series [2,4,5, (Table 1).…”

Progress in Intraoperative Neurophysiological Monitoring for the Surgical Treatment of Thoracic Spinal Stenosis

“…34 suggested that the MAP should be maintained at >81 mmHg to reduce neurological deterioration in thoracic decompression. When all above methods failed to regain signals, the position of the internal fixation instruments should be checked, and local kyphosis of the decompressed segments should be corrected.…”