Comparison of Fusion Rate between Demineralized Bone Matrix versus Autograft in Lumbar Fusion : Meta-Analysis

The demineralized bone matrix (DBM) as the bone graft material to increase the fusion rate was widely used in spinal fusion. The current study aimed to compare the fusion rate of DBM to the fusion rate of autograft in lumbar spine fusion via meta-analysis of published literature. After systematic search, comparative studies were selected according to eligibility criteria. Checklist (risk of bias assessment tool for non-randomized study) was used to evaluate the risk of bias of the included nonrandomized controlled studies. The corresponding 95% confidence interval (95% CI) were calculated. We also used subgroup analysis to analyze the fusion rate of posterolateral lumbar fusion and lumbar interbody fusion. Eight studies were finally included in this meta-analysis. These eight studies included 581 patients. Among them, 337 patients underwent spinal fusion surgery using DBM (DBM group) and 204 patients underwent spinal fusion surgery with mainly autologous bone and without using DBM (control group). There was no significant differences of fusion rate between the two groups in posterolateral fusion analysis (risk ratio [RR], 1.03; 95% CI, 0.90–1.17; p=0.66) and interbody fusion analysis (RR, 1.13; 95% CI, 0.91–1.39; p=0.27). Based on the available evidence, the use of DBM with autograft in posterolateral lumbar spine fusion and lumbar interbody fusion showed a slightly higher fusion rate than that of autograft alone; however, there was no statistically different between two groups.

Changes of Biomarkers before and after Antibiotic Treatment in Spinal Infection / 대한신경손상학회지

OBJECTIVE: The laboratory biomarkers used to diagnose spinal infection include white blood cell (WBC) counts, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP). Recently, procalcitonin (PCT) has been used as a biomarker to distinguish between bacterial infection and non-bacterial infection. We aimed to compare the changes of conventional biomarker and PCT in patients with spinal infection before and after antibiotic treatment. METHODS: ESR, CRP, WBC counts, and PCT were measured in 29 patients diagnosed with pyogenic spinal infection at our hospital between May 2016 and December 2018 prior to antibiotic administration. After antibiotic administration, the values were followed up for 4 weeks at 1-week intervals. RESULTS: A total of 29 patients were enrolled, with a mean age of 67.8 years, consisting of 16 men and 13 women. Twenty-five patients had lumbar infections, and 2 each had cervical and thoracic infections. The mean ESR, CRP, PCT, and WBCs decreased at week 4 of antibiotic treatment compared to their baseline values. CRP and WBCs were significantly decreased after 4 weeks of treatment compared to before treatment. The mean ESR and PCT was not statistically significant compared to pretreatment and after antibiotic treatment (p-value>0.05). CONCLUSION: Among several biomarker, CRP and WBCs are biomarkers that can aid early evaluation of the effects of antibiotic treatment in pyogenic spondylitis. Although PCT did not have statistical significance, it can be used as a biomarker that reflects the effect of antibiotic and severity of infection.

Cervical Cerebrospinal Fluid Leakage Concomitant with a Thoracic Spinal Intradural Arachnoid Cyst / 대한신경손상학회지

We encountered a very rare case of spontaneous spinal cerebrospinal fluid (CSF) leakage and a spinal intradural arachnoid cyst (AC) that were diagnosed at different sites in the same patient. These two lesions were thought to have interfered with the disease onset and deterioration. A 30-year-old man presented with sudden neck pain and orthostatic headache. Diplopia, ophthalmic pain, and headache deteriorated. CSF leakage was confirmed in C2 by radioisotope cisternography, and an epidural blood patch was performed. While his symptoms improved gradually, paraparesis suddenly progressed. Thoracolumbar magnetic resonance imaging (MRI) revealed an upper thoracic spinal intradural AC, which was compressing the spinal cord. We removed the outer membrane of the AC and performed fenestration of the inner membrane after T3-4 laminectomy. Postoperative MRI showed complete removal of the AC and normalized lumbar subarachnoid space. All neurological deficits including motor weakness, sensory impairment, and voiding function improved to normal. We present a case of spontaneous spinal CSF leakage and consecutive intracranial hypotension in a patient with a spinal AC. Our report suggests that if spinal CSF leakage and a spinal AC are diagnosed in one patient, even if they are located at different sites, they may affect disease progression and aggravation.

Cushing Syndrome: A Potential Risk of Bilateral Postoperative Ischemic Optic Neuropathy after Lumbar Fusion / 대한신경손상학회지

This is a report of a 58-year-old female with Cushing syndrome who underwent posterior lumbar fusion and lost both her vision completely. She was diagnosed with posterior ischemic optic neuropathy. Cushingoid features such as buffalo hump and central obesity might have attributed in triggering posterior ischemic optic neuropathy. When laid prone for surgery, perioperative high abdominal pressure causes venous hypertension leading to increase amount of blood loss. To compensate, infusion of large quantities of intravenous fluids is necessary which leads to hemodilution which decreases ocular perfusion pressure. Hypercoagulability of Cushing syndrome is also potentially a risk factor of this condition which increases the incidence of venous thromboembolism. For there is no known effective treatment for posterior ischemic optic neuropathy, means to prevent this complication must be strategically reviewed. When performing long spine surgery on patient who has Cushing syndrome or cushingoid features, caution must be taken to avoid this devastating complication.

Spontaneous Spinal Subdural and Subarachnoid Hemorrhage with Concomitant Intracerebral Hemorrhage: A Case Report / 대한신경손상학회지

Most cases of spinal subdural hematoma are very rare and result from iatrogenic causes, such as coagulopathy or a spinal puncture. Cases of non-traumatic spinal subdural hematoma accompanied by intracranial hemorrhage are even more rare. There are a few reports of spontaneous spinal subdural hematoma with concomitant intracranial subdural or subarachnoid hemorrhage, but not with intracerebral hemorrhage. Especially in our case, the evaluation and diagnosis were delayed because the spontaneous intracerebral hemorrhage accompanying the unilateral spinal subdural and subarachnoid hemorrhages caused hemiplegia. We report a case of spinal subdural and subarachnoid hemorrhage with concomitant intracerebral hemorrhage, for the first time, with a relevant literature review.

Total Deformity Angular Ratio as a Risk Factor for Complications after Posterior Vertebral Column Resection Surgery

OBJECTIVE: The aim of the present study was to identify whether the deformity angular ratio (DAR) influences the occurrence of complications after posterior vertebral column resection (PVCR) and to establish the DAR cut-off value. METHODS: Thirty-six consecutive patients undergoing PVCR from December 2010 to October 2016 were reviewed. The relationships between the total, sagittal, and coronal DAR and complications were assessed using receiver operator characteristics curves. The patients were divided into two groups according to a reference value based on the cut-off value of DAR. Demographic, surgical, radiological, and clinical outcomes were compared between the groups. RESULTS: There were no significant differences in the patient demographic and surgical data between the groups. The cut-off values for the total DAR (T-DAR) and the sagittal DAR (S-DAR) were 20.2 and 16.4, respectively (p=0.018 and 0.010). Both values were significantly associated with complications (p=0.016 and 0.005). In the higher T-DAR group, total complications (12 vs. 21, p=0.042) and late-onset complications (3 vs. 9, p=0.036) were significantly correlated with the T-DAR. The number of patients experiencing complications (9 vs. 11, p=0.029) and the total number of complications (13 vs. 20, p=0.015) were significantly correlated with the S-DAR. Worsening intraoperative neurophysiologic monitoring was more frequent in the higher T-DAR group (2 vs. 4) than in the higher S-DAR group (3 vs. 3). There was no difference in neurological deterioration between the groups after surgery. CONCLUSION: Both the T-DAR and the S-DAR are risk factors for complications after PVCR. Those who had a T-DAR >20.2 or S-DAR >16.4 experienced a higher rate of complications after PVCR.

Instrumentation Failure after Partial Corpectomy with Instrumentation of a Metastatic Spine

OBJECTIVE: To identify the perioperative factors associated with instrument failure in patients undergoing a partial corpectomy with instrumentation (PCI) for spinal metastasis. METHODS: We assessed the one hundred twenty-four patients with who underwent PCI for a metastatic spine from 1987 to 2011. Outcome measure was the risk factor related to implantation failure. The preoperative factors analyzed were age, sex, ambulation, American Spinal Injury Association grade, bone mineral density, use of steroid, primary tumor site, number of vertebrae with metastasis, extra-bone metastasis, preoperative adjuvant chemotherapy, and preoperative spinal radiotherapy. The intraoperative factors were the number of fixed vertebrae, fixation in osteolytic vertebrae, bone grafting, and type of surgical approach. The postoperative factors included postoperative adjuvant chemotherapy and spinal radiotherapy. This study was supported by the National Research Foundation grant funded by government. There were no study-specific biases related to conflicts of interest. RESULTS: There were 15 instrumentation failures (15/124, 12.1%). Preoperative ambulatory status and primary tumor site were not significantly related to the development of implant failure. There were no significant associations between insertion of a bone graft into the partial corpectomy site and instrumentation failure. The preoperative and operative factors analyzed were not significantly related to instrumentation failure. In univariable and multivariable analyses, postoperative spinal radiotherapy was the only significant variable related to instrumentation failure (p=0.049 and 0.050, respectively). CONCLUSION: When performing PCI in patients with spinal metastasis followed by postoperative spinal radiotherapy, the surgeon may consider the possibility of instrumentation failure and find other strategies for augmentation than the use of a bone graft for fusion.

Total Deformity Angular Ratio as a Risk Factor for Complications after Posterior Vertebral Column Resection Surgery

OBJECTIVE: The aim of the present study was to identify whether the deformity angular ratio (DAR) influences the occurrence of complications after posterior vertebral column resection (PVCR) and to establish the DAR cut-off value.METHODS: Thirty-six consecutive patients undergoing PVCR from December 2010 to October 2016 were reviewed. The relationships between the total, sagittal, and coronal DAR and complications were assessed using receiver operator characteristics curves. The patients were divided into two groups according to a reference value based on the cut-off value of DAR. Demographic, surgical, radiological, and clinical outcomes were compared between the groups.RESULTS: There were no significant differences in the patient demographic and surgical data between the groups. The cut-off values for the total DAR (T-DAR) and the sagittal DAR (S-DAR) were 20.2 and 16.4, respectively (p=0.018 and 0.010). Both values were significantly associated with complications (p=0.016 and 0.005). In the higher T-DAR group, total complications (12 vs. 21, p=0.042) and late-onset complications (3 vs. 9, p=0.036) were significantly correlated with the T-DAR. The number of patients experiencing complications (9 vs. 11, p=0.029) and the total number of complications (13 vs. 20, p=0.015) were significantly correlated with the S-DAR. Worsening intraoperative neurophysiologic monitoring was more frequent in the higher T-DAR group (2 vs. 4) than in the higher S-DAR group (3 vs. 3). There was no difference in neurological deterioration between the groups after surgery.CONCLUSION: Both the T-DAR and the S-DAR are risk factors for complications after PVCR. Those who had a T-DAR >20.2 or S-DAR >16.4 experienced a higher rate of complications after PVCR.

Instrumentation Failure after Partial Corpectomy with Instrumentation of a Metastatic Spine

OBJECTIVE: To identify the perioperative factors associated with instrument failure in patients undergoing a partial corpectomy with instrumentation (PCI) for spinal metastasis.METHODS: We assessed the one hundred twenty-four patients with who underwent PCI for a metastatic spine from 1987 to 2011. Outcome measure was the risk factor related to implantation failure. The preoperative factors analyzed were age, sex, ambulation, American Spinal Injury Association grade, bone mineral density, use of steroid, primary tumor site, number of vertebrae with metastasis, extra-bone metastasis, preoperative adjuvant chemotherapy, and preoperative spinal radiotherapy. The intraoperative factors were the number of fixed vertebrae, fixation in osteolytic vertebrae, bone grafting, and type of surgical approach. The postoperative factors included postoperative adjuvant chemotherapy and spinal radiotherapy. This study was supported by the National Research Foundation grant funded by government. There were no study-specific biases related to conflicts of interest.RESULTS: There were 15 instrumentation failures (15/124, 12.1%). Preoperative ambulatory status and primary tumor site were not significantly related to the development of implant failure. There were no significant associations between insertion of a bone graft into the partial corpectomy site and instrumentation failure. The preoperative and operative factors analyzed were not significantly related to instrumentation failure. In univariable and multivariable analyses, postoperative spinal radiotherapy was the only significant variable related to instrumentation failure (p=0.049 and 0.050, respectively).CONCLUSION: When performing PCI in patients with spinal metastasis followed by postoperative spinal radiotherapy, the surgeon may consider the possibility of instrumentation failure and find other strategies for augmentation than the use of a bone graft for fusion.