Large Increase in Blood Pressure After Extubation and High Body Mass Index Elevate the Risk of Spinal Epidural Hematoma After Spinal Surgery

The significance of metabolic disease in degenerative cervical myelopathy: a systematic review

Introduction

Degenerative cervical myelopathy (DCM) is a form of chronic spinal cord injury, with a natural history of potential for progression over time. Whilst driven by mechanical stress on the spinal cord from degenerative and congenital pathology, the neurological phenotype of DCM is likely to be modified by multiple systemic factors. The role of metabolic factors is therefore of interest, particularly given that ischaemia is considered a key pathological mechanism of spinal cord injury. The objective was therefore to synthesise current evidence on the effect of metabolism on DCM susceptibility, severity, and surgical outcomes.

Methods

A systematic review in MEDLINE and Embase was conducted following PRISMA guidelines. Full-text papers in English, with a focus on DCM and metabolism, including diabetes, cardiovascular disease, anaemia, and lipid profile, were eligible for inclusion. Risk of methodological bias was assessed using the Joanna Briggs Institute (JBI) critical assessment tools. Quality assessments were performed using the GRADE assessment tool. Patient demographics, metabolic factors and the relationships between metabolism and spinal cord disease, spinal column disease and post-operative outcomes were assessed.

Results

In total, 8,523 papers were identified, of which 57 met criteria for inclusion in the final analysis. A total of 91% (52/57) of included papers assessed the effects of diabetes in relation to DCM, of which 85% (44/52) reported an association with poor surgical outcomes; 42% of papers (24/57) discussed the association between cardiovascular health and DCM, of which 88% (21/24) reported a significant association. Overall, DCM patients with diabetes or cardiovascular disease experienced greater perioperative morbidity and poorer neurological recovery. They were also more likely to have comorbidities such as obesity and hyperlipidaemia.

Conclusion

Metabolic factors appear to be associated with surgical outcomes in DCM. However, evidence for a more specific role in DCM susceptibility and severity is uncertain. The pathophysiology and natural history of DCM are critical research priorities; the role of metabolism is therefore a key area for future research focus.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42021268814.

Unilateral Neurological Deficit Due to Spinal Epidural Hematoma Following Midline-Sparing Spine Surgery: A Case Report

Symptomatic spinal epidural hematoma (SEH) is a rare but well-documented complication in spine surgery, often associated with risk factors such as abnormal coagulation parameters, low platelets, excessive epidural bleeding, and inadequate hemostasis. While bilateral SEH is frequently described in the literature, unilateral SEH following spine surgery is seldom reported. We present a unique case of a unilateral neurological deficit resulting from an SEH following midline-sparing spine surgery due to unilateral drain placement in an 80-year-old male patient without comorbidities and normal coagulation parameters. Subsequent evacuation of the hematoma was done leading to gradual recovery of neurology. This emphasizes the importance of bilateral drain placement in such midline-sparing spine surgeries. This report underscores the significance of early SEH diagnosis and intervention, providing valuable insights into preventive measures and the need for a high index of suspicion in managing this potentially debilitating complication.

Systemic Hypertension and Postoperative Symptomatic Spinal Epidural Hematoma: A Scoping Review

Postoperative symptomatic spinal epidural hematoma (PSSEH) is a serious complication of spinal surgery that is associated with significant morbidity. Studies suggest that hypertension is a risk factor for the development of PSSEH. The aim of this review was to evaluate the literature reporting associations between hypertension and PSSEH. A comprehensive literature search was conducted using the MEDLINE/PubMed, Embase, and Cochrane Library databases to identify studies that investigated PSSEH and reported data on preoperative hypertension status and/or perioperative blood pressure (BP). Eighteen studies were identified for inclusion in the review. Observational data suggested that uncontrolled/untreated preoperative hypertension, extubation-related increases in systolic BP, and elevated postoperative systolic BP were associated with an increased risk of PSSEH. The overall quality of evidence was low because of the retrospective nature of the studies, heterogeneity, and lack of precision in reporting. Despite the limitations of the current evidence, our findings could be important in establishing preoperative BP targets for elective spine surgery and inform perioperative clinical decision-making, while allowing consideration of risk factors for PSSEH. Well-controlled studies are required to investigate further the relationship between BP and PSSEH.

Risk factors of epidural hematoma in patients undergoing spinal surgery: a meta-analysis of 29 cohort studies

OBJECTIVE

The authors conducted this meta-analysis to identify risk factors for spinal epidural haematoma (SEH) among patients following spinal surgery.

METHODS

The authors systematically searched Pub: Med, Embase, and the Cochrane Library for articles that reported risk factors associated with the development of SEH in patients undergoing spinal surgery from inception to 2 July 2022. The pooled odds ratio (OR) was estimated using a random-effects model for each investigated factor. The evidence of observational studies was classified as high quality (Class I), moderate quality (Class II or III) and low quality (Class IV) based on sample size, Egger's P value and between-study heterogeneity. In addition, subgroup analyses stratified by study baseline characteristics and leave-one-out sensitivity analyses were performed to explore the potential sources of heterogeneity and the stability of the results.

RESULTS

Of 21 791 articles screened, 29 unique cohort studies comprising 150 252 patients were included in the data synthesis. Studies with high-quality evidence showed that older patients (≥60 years) (OR, 1.35; 95% CI, 1.03-1.77) were at higher risk for SEH. Studies with moderate-quality evidence suggested that patients with a BMI greater than or equal to 25 kg/m² (OR, 1.39; 95% CI, 1.10-1.76), hypertension (OR, 1.67; 95% CI, 1.28-2.17), and diabetes (OR, 1.25; 95% CI, 1.01-1.55) and those undergoing revision surgery (OR, 1.92; 95% CI, 1.15-3.25) and multilevel procedures (OR, 5.20; 95% CI, 2.89-9.37) were at higher risk for SEH. Meta-analysis revealed no association between tobacco use, operative time, anticoagulant use or American Society of Anesthesiologists (ASA) classification and SEH.

CONCLUSIONS

Obvious risk factors for SEH include four patient-related risk factors, including older age, obesity, hypertension and diabetes, and two surgery-related risk factors, including revision surgery and multilevel procedures. These findings, however, must be interpreted with caution because most of these risk factors had small effect sizes. Nonetheless, they may help clinicians identify high-risk patients to improve prognosis.

Severe Symptomatic Epidural Hematoma Following Percutaneous Endoscopic Unilateral Laminectomy for Bilateral Decompression (Endo-ULBD)-Series Report and Management Strategies

OBJECTIVES

Severe symptomatic epidural hematoma (SSEH) is one of the most severe complications following percutaneous endoscopic unilateral laminectomy for bilateral decompression (Endo-ULBD). Considering that this technique has been performed for a short time, no detailed reports have been recently published. Thus, it is critical to gain a better understanding of SSEH occurring in its postoperative period with regard to its incidence, possible causes, outcome, etc., in order to identify relevant management strategies.

METHODS

Patients with spinal stenosis who had undergone Endo-ULBD in our department from May 2019 to May 2022 were retrospectively analyzed. Of which, patients with postoperative epidural hematoma were followed-up. The preoperative and postoperative physical conditions of each patient were recorded, and the information related to hematoma removal surgery was recorded in detail. Clinical outcomes were assessed using the visual analogue scale (VAS) and Oswestry disability index (ODI), and the results were classified into "excellent," "good," "fair," or "poor" based on the modified MacNab criteria. The incidence of hematoma with different factors was calculated, and a bar graph was used to compare the difference of the indexes related to hematoma removal between cases, and a line graph was used to reflect the trend of the outcome of each patient within 6 months to evaluate the effect of the treatment.

RESULTS

A total of 461 patients with spinal stenosis who underwent Endo-ULBD were enrolled in the study. SSEH occurred in four cases, with an incidence rate of 0.87% (4/461). All these four patients underwent decompression of multiple segments, and three of them had a history of hypertension comorbid with diabetes. Notably, one patient had a past history of hypertension and coronary artery disease and was on postoperative low molecular heparin due to lower extremity venous thrombosis. According to the conditions of the four patients, three types of treatment were used. And with timely treatment, all patients recovered well.

CONCLUSION

Despite being a minimally invasive technique, postoperative epidural hematoma remains a severe complication of Endo-ULBD. Therefore, during percutaneous endoscopic surgery, it is essential to enhance the comprehensive perioperative management of patients with Endo-ULBD. Signs related to postoperative hematoma must be recognized and promptly managed. If necessary, satisfactory results can be achieved by using percutaneous endoscopy along the original surgical channel to remove the hematoma.

The Influence of Systolic Blood Pressure at the Time of Extubation on the Development of Postoperative Spinal Epidural Hematoma

Background

The most common cause of neurological complications after a biportal endoscopic spine surgery (BESS) is postoperative spinal epidural hematomas (POSEH). The objective of this study was to determine the influence of systolic blood pressure at extubation (e-SBP) on POSEH.

Methods

A total of 352 patients who underwent single-level decompression surgery including laminectomy and/or discectomy with BESS under the diagnosis of spinal stenosis and herniated nucleus pulposus between August 1, 2018, and June 30, 2021, were reviewed retrospectively. The patients were divided into two, a POSEH group and a normal group without POSEH (no neurological complication). The e-SBP, demographic factors, and the preoperative and intraoperative factors suspected to influence the POSEH were analyzed. The e-SBP was converted to a categorical variable by the threshold level that was decided by maximum area under the curve (AUC) in receiver operating characteristic (ROC) curve analysis. Antiplatelet drugs (APDs) were taken in 21 patients (6.0%), discontinued in 24 patients (6.8%), and not taken in 307 patients (87.2%). Tranexamic acid (TXA) was used in 292 patients (83.0%) in the perioperative period.

Results

Of the 352 patients, 18 patients (5.1%) underwent revision surgery for the removal of POSEH. The POSEH and normal groups were homogenous in age, sex, diagnosis, operation segments, operation time, and lab findings that were related to blood clotting, whereas there were differences in e-SBP (163.7 ± 15.7 mmHg in POSEH group and 154.1 ± 18.3 mmHg in normal group), APD (4 takers, 2 stoppers, 12 non-takers in POSEH group and 16 takers, 22 stoppers, 296 non-takers in normal group), and TXA (12 use, 6 not use in POSEH group and 280 use, 54 not use in normal group) in single variable analysis. The highest AUC in the ROC curve analysis was 0.652 for 170 mmHg e-SBP (p < 0.05). There were 94 patients in the high e-SBP group (≥ 170 mmHg) and 258 patients in the low e-SBP group. In multivariable logistic regression analysis, only high e-SBP was a significant risk factor for POSEH (p = 0.013; odds ratio, 3.434).

Conclusions

High e-SBP (≥ 170 mmHg) can influence the development of POSEH in biportal endoscopic spine surgery.

Characteristics of the Patients with Poor Clinical Outcomes After Symptomatic Postoperative Lumbar Epidural Hematoma

OBJECTIVE

Symptomatic postoperative lumbar epidural hematoma (PLEH) may lead to poor outcomes even after evacuation. This study aimed to verify the short-term clinical outcomes after the evacuation of PLEH and to clarify the characteristics of the patients with poor postoperative outcomes.

METHODS

Twenty-five patients (average age; 70.4 years) underwent PLEH evacuation after lumbar spine surgery. The mean follow-up period was 12.0 (range 3-37) months. Pre and postoperative Japanese Orthopedic Association scores and visual analog scale (VAS) of low back pain (LBP), leg pain, and leg numbness were retrospectively collected. The dural sac cross-sectional area at the most compressed level was measured on magnetic resonance imaging. The patients were classified into 2 groups: poor outcome group (P group) had less than 50% of Japanese Orthopedic Associationrecovery rate and good group (G group) with 50% or more recovery rate.

RESULTS

The rate of delayed evacuation (over 24 hours of onset) was significantly higher in P group than in G group (P = 0.027). There was no significant difference in dural sac cross-sectional areabetween the 2 groups (P = 0.438). VAS of LBP, leg pain, and leg numbness in G group significantly improved postoperatively. Although VAS of LBP and leg pain in P group significantly improved postoperatively, there was no significant difference between the pre and postoperative VAS of leg numbness.

CONCLUSIONS

Delayed evacuation of PLEH can lead to poor postoperative outcomes after lumbar spine surgery. Moreover, patients with poor outcomes remained with postoperative leg numbness. Early evacuation of symptomatic PLEH is key to avoid poor outcomes and persistent leg numbness.

Incidence of postoperative symptomatic spinal epidural hematoma requiring surgical evacuation: a systematic review and meta-analysis

PURPOSE

This systematic review and meta-analysis aimed to determine the incidence of symptomatic spinal epidural hematoma (SSEH) following spine surgery.

METHODS

We systematically searched for all relevant articles that mentioned the incidence of SSEH following the spine surgery published in the PubMed, Embase, and Cochrane Library databases through March 2022 and manually searched the reference lists of included studies. The Newcastle-Ottawa quality assessment scale (NOS) was used to assess the quality of the included studies. A fixed-effects or random-effects model was performed to calculate the pooled incidence of the totality and subgroups based on the heterogeneity. The potential publication bias was assessed by Egger's linear regression and a funnel plot. Sensitivity analysis was also conducted.

RESULTS

A total of 40 studies were included in our meta-analysis based on our inclusion and exclusion criteria. The overall pooled incidence of SSEH was 0.52% (95% CI 0.004-0.007). In the subgroup analysis, the pooled incidence of SSEH in males and females was 0.86% (95% CI 0.004-0.023) and 0.68% (95% CI 0.003-0.017). Among the different indications, a higher incidence (2.9%, 95% CI 0.006-0.084) was found in patients with deformity than degeneration (1.12%, 95% CI 0.006-0.020) and tumor (0.30%, 95% CI 0.006-0.084). For different surgical sites, the incidences of SSEH in cervical, thoracic and lumbar spine were 0.32% (95% CI 0.002-0.005), 0.84% (95% CI 0.004-0.017) and 0.63% (95% CI 0.004-0.010), respectively. The incidences of SSEH in anterior and posterior approach were 0.24% (95% CI 0.001-0.006) and 0.70% (95% CI 0.004-0.011), respectively. The pooled incidence of SSEH was five times higher with minimally invasive surgery (1.94%, 95% CI 0.009-0.043) than with open surgery (0.42%, 95% CI 0.003-0.006). Delayed onset of SSEH had a lower incidence of 0.16% (95% CI 0.001-0.002) than early onset. There were no significant variations in the incidence of SSEH between patients who received perioperative anticoagulation therapy and those who did not or did not report getting chemopreventive therapy (0.44%, 95% CI 0.006-0.084 versus 0.42%, 95% CI 0.003-0.006).

CONCLUSION

We evaluated the overall incidence proportion of SSEH after spine surgery and performed stratified analysis, including sex, surgical indication, site, approach, minimally invasive surgery, and delayed onset of SSEH. Our research would be helpful for patients to be accurately informed of their risk and for spinal surgeons to estimate the probability of SSEH after spine surgery.

Increased Surgical Experience in Microendoscopic Spinal Surgery Can Reduce Development of Postoperative Spinal Epidural Hematoma and Improve the Clinical Outcomes

No reports have previously evaluated the association between surgical technique and the incidence of postoperative spinal epidural hematoma (PSEH) following microendoscopic decompression surgery (MED). This study aimed to evaluate the association between the development of radiographic PSEH (rPSEH) following MED and microendoscopic surgical experience and postoperative clinical outcomes related to the quality of life (QoL). This retrospective cohort study included 3922 patients who had undergone MED performed by a single surgeon. rPSEH was defined as a hematoma that was identified via routine magnetic resonance images performed 3−4 days postoperatively. Patients were divided into rPSEH and control groups to identify the risk factor of rPSEH and assess clinical outcomes. In the multivariate analysis, age (p = 0.002), surgical experience (p = 0.003), surgical time (p = 0.038), multilevel decompression (p < 0.001), and diagnosis (p = 0.004) were identified as independent variables associated with rPSEH. Moreover, in mixed-effect models, the rPSEH group showed less improvement in Oswestry Disability Index (p = 0.014) than the control group. In conclusion, the surgical experience was identified as a risk factor for rPSEH that could lead to poor QoL. The sharing of microendoscopic surgical techniques among surgeons may reduce rPSEH incidence and improve patients’ QoL.

[Research progress of unilateral biportal endoscopy technique in treatment of lumbar related diseases]

Objective

To review the application and research progress of unilateral biportal endoscopy (UBE) technique in the treatment of lumbar related diseases.

Methods

The domestic and foreign literature on the application of UBE technique in the treatment of lumbar related diseases was extensively consulted, and the development history, clinical application, operation points and precautions, related complications and adverse reactions, advantages and disadvantages of the technique were reviewed.

Results

As a minimally invasive technique developed in recent years, UBE technique is effective in the treatment of lumbar spinal stenosis caused by different causes, with satisfactory decompression effect, less damage, and good lumbar stability. UBE technique has significant advantages over open surgery and microscopy-assisted surgery in the treatment of lumbar disc herniation. In the treatment of lumbar spondylolisthesis, the postoperative trauma of UBE technique is less than that of conventional surgery, and the fusion rate is satisfactory. There are also complications such as spinal cord injury, spinal epidural hematoma, incomplete decompression or recurrence, nerve root irritation symptoms, and postoperative infection in the treatment of lumbar related diseases with UBE technique. Detailed preoperative planning is essential for patients with lumbar related diseases who are suitable for UBE surgery.

Conclusion

UBE technique is easy to operate, has a gentle learning curve, can use conventional instruments, and has definite effectiveness. It is suitable for a variety of lumbar related diseases, but there are some defects and deficiencies.

The Influence of High Blood Pressure on Developing Symptomatic Lumbar Epidural Hematoma after Posterior Lumbar Spinal Fusion Surgery: Clinical Data Warehouse Analysis

Background: Determining the risk factors for symptomatic lumbar epidural hematoma (SLEH) is important for preventing postoperative SLEH. However, the relationship between blood pressure and SLEH is still debatable. The purpose of our study was to determine the risk factors for postoperative SLEH, to assess the influence of high blood pressure on developing SLEH after posterior lumbar spinal fusion surgery, and to evaluate the usefulness of big data analysis utilizing a clinical data warehouse (CDW). Methods: The clinical data of patients who had undergone posterior lumbar spinal fusion surgery were acquired from the CDW of Hallym University Medical Center. The acquired clinical data were compared between patients without postoperative SLEH and with postoperative SLEH. Results: Postoperative SLEH that required hematoma evacuation surgery within 72 h after posterior lumbar spinal fusion surgery occurred in 17 (1.3%) of 1313 patients. According to the multivariate logistic regression analysis, the risk factors for postoperative SLEH are platelet count difference (OR 1.28, p = 0.03), postoperative international normalized ratio (INR) difference (OR 31.4, p = 0.028), and postoperative systolic blood pressure (SBP) difference (≥10 mmHg) (OR 1.68, p = 0.048). An increase in postoperative SBP (OR 1.68, p = 0.048) had a statistically significant influence on the occurrence of postoperative SLEH. Conclusions: Big data analysis utilizing a CDW could be useful for extending our knowledge of the risk factors for postoperative SLEH and preventing postoperative SLEH after posterior lumbar spinal fusion surgery.

Incidence and Risk Factors for Symptomatic Spinal Epidural Hematoma Following Posterior Thoracic Spinal Surgery in a Single Institute

STUDY DESIGN

Case-control study.

OBJECTIVES

To investigate the incidence of symptomatic spinal epidural hematoma (SSEH) and recognize its risk factors in a cohort of patients undergoing posterior thoracic surgery in isolation.

METHODS

From January 2010 to December 2019, patients who developed SSEH after posterior thoracic surgery and underwent hematoma evacuation were enrolled. For each SSEH patient, 2 or 3 controls who did not develop SSEH and underwent the same procedures with similar complexity at the same section of the thoracic spine in the same period were collected. The preoperative and intraoperative factors, blood pressure-related factors and radiographic parameters were collected to identify possible risk factors by comparing between the 2 groups.

RESULTS

A total of 24 of 1612 patients (1.49%) were identified as having SSEH after thoracic spinal surgery. Compared to the control group (53 patients), SSEH patients had significant differences in the APTT (p = 0.028), INR (p = 0.009), ratio of previous spinal surgery (p = 0.012), ratio of cerebrospinal fluid leakage (p = 0.004), thoracic kyphosis (p<0.05), local kyphosis angle (p<0.05), epidural fat ratio at T7 (p = 0.003), occupying ratio of the cross-sectional area (p<0.05) and spinal epidural venous plexus grade (p<0.05). Multiple logistic regression analysis revealed 3 risk factors for SSEH: cerebrospinal fluid leakage, the local kyphosis angle (>8.77°) and the occupying ratio of the cross-sectional area (>49.58%).

CONCLUSIONS

The incidence of SSEH was 1.49% in posterior thoracic spinal surgeries. Large local kyphosis angle (>8.77°), high occupying ratio of cross-sectional area (>49.58%) and cerebrospinal fluid leakage were identified as risk factors for SSEH.

Obesity and Spine Surgery: A Qualitative Review About Outcomes and Complications. Is It Time for New Perspectives on Future Researches?

STUDY DESIGN

Literature review.

OBJECTIVES

An increasing number of obese patients requires operative care for degenerative spinal disorders. The aim of this review is to analyze the available evidence regarding the role of obesity on outcomes after spine surgery. Peri-operative complications and clinical results are evaluated for both cervical and lumbar surgery. Furthermore, the contribution of MIS techniques for lumbar surgery to play a role in reducing risks has been analyzed.

METHODS

Only articles published in English in the last 10 years were reviewed. Inclusion criteria of the references were based on the scope of this review, according to PRISMA guidelines. Moreover, only paper analyzing obesity-related complications in spine surgery have been selected and thoroughly reviewed. Each article was classified according to its rating of evidence using the Sacket Grading System.

RESULTS

A total number of 1636 articles were found, but only 130 of them were considered to be relevant after thorough evaluation and according to PRISMA checklist. The majority of the included papers were classified according to the Sacket Grading System as Level 2 (Retrospective Studies).

CONCLUSION

Evidence suggest that obese patients could benefit from spine surgery and outcomes be satisfactory. A higher rate of peri-operative complications is reported among obese patients, especially in posterior approaches. The use of MIS techniques plays a key role in order to reduce surgical risks. Further studies should evaluate the role of multidisciplinary counseling between spine surgeons, nutritionists and bariatric surgeons, in order to plan proper weight loss before elective spine surgery.

Factors Affecting Postoperative Spinal Epidural Hematoma and the Optimal Order of Vertebral Body Decompression in Multivertebral Microendoscopic Laminectomy

Purpose

Symptomatic postoperative spinal epidural hematoma (POSEH) is a complication of spine surgery that occurs infrequently but may cause ongoing serious neurological damage. Due to the narrow entry portal, the risk of hematoma is increased after microendoscopic laminectomy (MEL) compared with conventional open surgery, and the risk might be even higher for multivertebral MEL (m-MEL). The purpose of this study was to clarify the factors affecting the development of POSEH after m-MEL and identify the optimal order for the decompression of vertebral bodies.

Methods

A total of 313 patients who underwent m-MEL from 2016 to 2020 were retrospectively assessed. The cohort comprised 238 patients who underwent two-level MEL, 67 who underwent three-level MEL, and eight who underwent four-level MEL. Symptomatic POSEH was defined as the presence of an epidural hematoma at the surgical site on MRI with symptoms such as lower extremity pain or muscle weakness. We elucidated the incidence of POSEH at each vertebral level and investigated the relationship between POSEH and possible risk factors such as clinical and operative variables.

Results

There were 41 patients in the POSEH group and 272 patients in the non-POSEH group. Seven patients in the POSEH group underwent reoperation. The occurrence of POSEH was related to the number of decompressed vertebral bodies. Patients who underwent L2/3 and L3/4 decompression at the end of the procedure also showed a higher incidence of POSEH at the surgical level.

Conclusion

In patients undergoing m-MEL, treatment of the upper lumbar vertebrae at the end of decompression surgery might be a risk factor for symptomatic POSEH. The incidence of POSEH was particularly increased at L2/3, suggesting that L2/3 decompression should not be performed at last and that careful hemostasis should be applied.

Risk Factors for Incidence of Postoperative Spinal Epidural Hematoma Following Multilevel Microendoscopic Laminectomy

Introduction

Due to the narrow portal of entry, microendoscopic laminectomy (MEL) is associated with a risk of postoperative spinal epidural hematoma (POSEH). This risk might be higher when performing multiple-level (m-) MEL. The purpose of this study is to clarify the incidence rate of POSEH following single-level (s-) and m-MEL by each interlaminar level and identify the risk factors for POSEH following m-MEL.

Methods

A total of 379 patients underwent MEL of the lumbar spine (s-MEL, n=141; m-MEL, n=238). We determined the incidence of POSEH following s-MEL and m-MEL by each interlaminar level. For m-MEL, we clarified the correlation between POSEH and possible risk factors, such as operative findings, the sequence of operated interlaminar levels, and the preoperative cross-sectional dural area (CSA) on magnetic resonance imaging.

Results

The incidence rate at L2/3 was significantly higher than that at L3/4 and L4/5. Patients who underwent L2/3 decompression at the end of the procedure showed a higher incidence of POSEH at the L2/3 level. Preoperative spinal stenosis was associated with POSEH at the L2/3 level, and CSA of 56 mm² was a predictive factor for POSEH. Logistic regression analysis revealed that both were significant risk factors.

Conclusions

In patients undergoing m-MEL, the incidence of POSEH is highest at the L2/3 level, and treatment of the L2/3 level at the end of the procedure and the presence of spinal stenosis are risk factors for POSEH.

Postoperative Epidural Hematoma

Symptomatic postoperative epidural hematomas are rare, with an incidence of 0.10% to 0.69%. Risk factors have varied in the literature, but multiple studies have reported advanced age, preoperative or postoperative coagulopathy, and multilevel laminectomy as risk factors for hematoma. The role of pharmacologic anticoagulation after spine surgery remains unclear, but multiple studies suggest it can be done safely with a low risk of epidural hematoma. Prophylactic suction drains have not been found to lower hematoma incidence. Most symptomatic postoperative epidural hematomas present within the first 24 to 48 hours after surgery but can present later. Diagnosis of a symptomatic hematoma requires correlation of clinical signs and symptoms with a compressive hematoma on MRI. Patients will usually first complain of a marked increase in axial pain, followed by radicular symptoms in the extremities, followed by motor weakness and sphincter dysfunction. An MRI should be obtained emergently, and if it confirms a compressive hematoma, surgical evacuation should be carried out as quickly as possible. The prognosis for neurologic improvement after evacuation depends on the time delay and the degree of neurologic impairment before evacuation.

Impact of acetylsalicylic acid (ASA) on postoperative hemorrhage in spinal lumbar surgery: Should preoperative ASA be discontinued for elective surgery?

OBJECTIVE

The application of acetylsalicylic acid (ASA) represents high evidence in the aging society due to primary and secondary prevention in cardiovascular disease and stroke. However, this presents a challenge for neurosurgeons in terms of preoperative and postoperative management of care. This study aimed to analyze the risk of bleeding by applying ASA before lumbar spinal surgery.

METHODS

Retrospective analysis of medical records of 3051 patients was performed from 2008 to 2018 who underwent lumbar surgery at our institution. The risk of postoperative hemorrhage was compared in patients treated with ASA versus patients without ASA treatment. Additionally, the relationship between discontinuation of ASA preoperatively (≥7 days) or no previous history of ASA versus continuation with ASA (<7 days) on postoperative hemorrhage was analyzed.

RESULTS

Postoperative hemorrhagic were observed in 2.1% (n = 63) of all lumbar operations. In 421 patients, the effect of ASA (<7 days) was still persistent at the time of surgery (ASA impact group). Of these, 12 (2.85%) patients had a hemorrhage. No significant differences were found in comparison to the No ASA impact group (p = 0.272). Sex (p = 0.003), hypertension (p = 0.015), recurrent surgery (p = 0.001) and use of hemostatic agents (p = 0.023) had a significant impact on postoperative hemorrhage.

CONCLUSION

The continuation of ASA medication is not associated with increased risk of postoperative hemorrhage after spinal surgery. However, sex, hypertension, recurrent surgery and the use of hemostatic agents under continued ASA treatment were found to be associated with an increased risk of hemorrhage.

Does prophylactic use of topical gelatin-thrombin matrix sealant affect postoperative drainage volume and hematoma formation following microendoscopic spine surgery? A randomized controlled trial

BACKGROUND CONTEXT

Microendoscopic spinal surgery has demonstrated efficacy and is increasingly utilized as a minimally invasive approach to neural decompression, but there is a theoretical concern that bleeding and postoperative epidural hematoma (PEH) may occur with increased frequency in a contained small surgical field. Hemostatic agents, such as topical gelatin-thrombin matrix sealant (TGTMS), are routinely used in spine surgery procedures, yet there has been no data on whether PEH is suppressed by these agents when administered in microendoscopic spine surgery.

PURPOSE

The purpose of this study was to investigate the effect of TGTMS on bleeding and PEH formation in lumbar micoroendoscopic surgery.

STUDY DESIGN

This is a randomized controlled trial (RCT) with additional prospective observational cohort.

PATIENT SAMPLE

Patients were registered from July 2017 to September 2018 and a hundred and three patients undergoing microendoscopic laminectomy for lumbar spinal stenosis at a single institution were enrolled in this study.

OUTCOME MEASURES

The primary outcome was the drainage volume within 48 hours after surgery. Secondary outcomes were the numerical rating scale (NRS) of leg pain on the second (NRS2) and seventh day (NRS7) after surgery and the hematoma area ratio (HAR) in horizontal images on magnetic resonance image (MRI).

METHODS

In the RCT, 41 cases that received TGTMS (F group) were compared with 41 control group cases (C group) that did not receive TGTMS at the end of the procedure. Drainage volume, NRS2, NRS7, and HAR on MRI were evaluated. Nineteen cases were excluded from the RCT (I group) due to difficulty of hemostasis during surgery and the intentional use of TGTMS for hemostasis. I group was compared with C group in the drainage volume and NRS of leg pain as a prospective observational study.

RESULTS

The RCT demonstrated no statistically significant difference in drainage volume between those receiving TGTMS (117.0±71.7; mean±standard deviation) and controls (125.0±127.0; p=.345). The NRS2 and NRS7 was 3.5±2.6 and 2.8±2.5 in the F group, respectively, and 3.1±2.6 and 2.1±2.3 in the C group, respectively. The HAR on MRI was 0.19±0.19 in the F group and 0.17±0.13 in the C group. There was no significant difference in postoperative leg pain and HAR (p=.644 for NRS2, p=.129 for NRS7, and p=.705 for HAR). In the secondary observational cohort, the drainage volume in the I group was 118.3±151.4, and NRS2 and NRS7 was 3.5±2.0 and 2.6±2.6, respectively. There were no statistically significant differences in drainage volume (p=.386) or postoperative NRS of leg pain between these two groups (p=.981 and .477 for NRS2 and NRS7, respectively).

CONCLUSIONS

The prophylactic use of TGTMS in patients undergoing microendoscopic laminotomy for lumbar spinal stenosis did not demonstrate any difference in postoperative bleeding or PEH. Nonetheless, for patients that had active bleeding that required the use of TGTMS, there was no evidence of difference in postoperative clinical outcomes relative to controls.

Unplanned hospital readmission after surgical treatment for thoracic spinal stenosis: incidence and causative factors

BACKGROUND

To assess the incidence and causative factors of unplanned hospital readmission within 90 days after surgical treatment of thoracic spinal stenosis (TSS).

METHODS

Hospital administrative database was queried to identify patients who underwent surgical treatment of TSS from July 2010 through December 2017. All unplanned readmissions within 90 days of discharge were reviewed for causes and the rate of unplanned readmissions was calculated. Patients of unplanned readmission were matched 1:3 to a control cohort without readmission.

RESULTS

Twenty-one patients (incidence of 1.7 % in 1239 patients) presented unplanned hospital readmission within a 90-day period and enrolled as the study group, 63 non-readmission patients (a proportion of 1: 3) were randomly selected as the control group. Causes of readmission include pseudomeningocele (8 patients; 38 %), CSF leakage combined with poor incision healing (6 patients; 29 %), wound dehiscence (2 patient; 9 %), surgical site infection (2 patients; 9 %), spinal epidural hematoma (1 patient; 5 %), inadequate original surgical decompression (2 patients; 9 %). Mean duration from re-admission to the first surgery was 39.6 ± 28.2 days, most of the patients readmitted at the first 40 days (66.7 %, 14/21 patients). When compared to the non-readmitted patients, diagnosis of OPLL + OFL, circumferential decompression, dural injury, long hospital stay were more to be seen in readmitted patients.

CONCLUSIONS

The incidence of 90-day unplanned readmission after surgical treatment for TSS is 1.7 %, CSF leakage and pseudomeningocele were the most common causes of readmission, the peak period of readmission occurred from 10 to 40 days after surgery, patients should be closely followed up within this period.

[Research progress in effect of obesity on the effectiveness of posterior lumbar fusion]

Objective

To review the effect of obesity on the effectiveness of posterior lumbar fusion in patients with lumbar degenerative diseases (LDD).

Methods

The related literature at home and abroad was extensively reviewed. And the difficulty of operation, risk of complications, and long-term effectiveness of posterior lumbar fusion for obese patients with LDD were summarized.

Results

Although some relevant literature suggest that the posterior lumbar fusion for obese patients is difficult and the risk of postoperative complications is high, the overall research results do not suggest that obesity is a risk factor for the implementation of posterior lumbar fusion. By assessing the physical condition of patients and strictly grasping the surgical indications, obese patients can obtain good surgical efficacy.

Conclusion

Posterior lumbar fusion is an effective method for the treatment of LDD in obese patients. However, relevant studies need to be completed to further evaluate the safety and efficacy of posterior lumbar fusion for obese patients.

Delayed Onset Postoperative Spinal Epidural Hematoma after Lumbar Spinal Surgery: Incidence, Risk Factors, and Clinical Outcomes

Background

Posterior spinal epidural haematoma (PSEH) often develops within 24 hours after surgery. On rare occasions, PSEH occurs after 3 days and up to two weeks and is classified as delayed-onset PSEH. Due to its rarity, previous studies have only described the clinical features, whereas risk factors have not been assessed.

Methods

Patients who developed PSEH requiring haematoma evacuation between December 2013 and January 2020 were included and divided into the early-onset (group A) and delayed-onset (group B) groups based on the time of symptom onset (>72 hours). For each PSEH patient, 3 controls (group C) who did not develop PSEH in the same period were randomly selected. Clinical features were compared among the three groups, and multiple logistic regression analysis was performed to identify the risk factors for groups A and B.

Results

Thirty-two patients (0.35%) were identified as having early-onset PSEH (occurring at 10.68 ± 11.5 h), and 15 (0.16%) patients had delayed-onset PSEH (occurring at 130.60 ± 61.78 h). When comparing groups A and B, group A showed a higher rate of multilevel procedures, lower drainage, lower APTT, and higher JOA score at discharge. Multiple logistic regression analysis identified multilevel procedures (OR: 5.62, 95% CI: 1.84-17.25), postoperative systolic blood pressure (SBP) (OR: 1.10, 95% CI: 1.06-1.15), and abnormal coagulation (OR: 5.68, 95% CI: 1.74-18.52) as independent risk factors for group A, whereas postoperative SBP (OR: 1.10, 95% CI: 1.04-1.16) and previous spinal surgery (OR: 4.74, 95% CI: 1.09-20.70) at the same level were risk factors for group B.

Conclusions

Our study revealed that the overall incidence of delayed-onset PSEH was 0.16% in posterior lumbar spinal surgery and that its risk was different from that of early-onset PSEH. If patients with such risk factors develop neurological deficits 3 days after initial surgery, surgeons should be aware of the possibility of delayed-onset PSEH.

Symptomatic Epidural Hematoma after Elective Posterior Lumbar Decompression: Incidence, Timing, Risk Factors, and Associated Complications

BACKGROUND

Symptomatic post-operative lumbar epidural hematoma (PLEH) is a complication of lumbar spine surgery that can cause permanent neurologic consequences through compression of the cauda equina and nerve roots.

QUESTIONS/PURPOSES

We sought to investigate the incidence, timing, and risk factors for symptomatic epidural hematomas following posterior lumbar decompression, as well as to identify additional post-operative complications associated with symptomatic lumbar epidural hematomas.

METHODS

Elective lumbar spine procedures were identified in the National Surgical Quality Improvement Program (NSQIP) database between 2012 and 2016. Analyzed predictors of reoperation or readmission within 30 days for symptomatic PLEH included demographics, comorbidities, pre-operative laboratory values, peri-operative characteristics, and post-operative complications.

RESULTS

There were 75,878 cases included in the analysis. The incidence rate of symptomatic PLEH was 0.27% (n = 206), 54.4% (n = 112) of which occurred within 5 days of the procedure. Increased age, obesity (body mass index of 35 or higher), peri-operative transfusion, multilevel surgery (two or more levels), dural tear repair, and microscope use were independently associated with PLEH. Post-operative complications associated with PLEH included surgical site infection and urinary tract infection.

CONCLUSIONS

Readmission or reoperation for symptomatic PLEH following elective lumbar spine surgery is rare and can occur many days or weeks after a procedure. There are modifiable risk factors for PLEH and associated additional post-operative complications that physicians should be suspicious of following posterior lumbar decompression.

Sharp systolic blood pressure elevation at extubation is a risk factor for symptomatic epidural hematoma after spine surgery

STUDY DESIGN

The present study is a single-center retrospective cohort study.

OBJECTIVE

The objective of the study is to verify the hypothesis that sharp elevation of systolic blood pressure at extubation is a risk factor for development of symptomatic epidural hematoma after spinal surgery.

SUMMARY OF BACKGROUND DATA

Postoperative symptomatic epidural hematoma (she) after spine surgery is a rare but potentially serious complication that may result in paralysis unless removed at an early stage.

METHODS

The subjects were 2611 patients treated with decompression and decompression/fusion of the cervical, thoracic, and lumbar vertebrae at our hospital. Twelve of these patients developed postoperative SEH and removal of hematoma was performed. To investigate the risk factors in these patients, data were analyzed for age at the time of surgery, sex, preoperative complications, medical history, body mass index, preoperative platelet count, surgical procedure, microscope use, operative time, blood loss, surgical site, systolic blood pressure (SBP) at extubation, difference between resting and extubation SBP, ratio of SBP at extubation to that at rest, blood pressure at discharge from the operating room, and use of a drain.

RESULTS

There was a significantly higher rate of SBP ratio (extubation/rest) ≥1.3 in patients with SEH (p = 0.021, Fisher's exact test). Among the preoperative complications and medical histories, the frequency of cerebrovascular disorder tended to be higher in SEH cases than in non-SEH cases (p = 0.073). There was no significant difference for all other parameters listed above. In multivariate logistic analysis, the odds ratios were 3.98 (p = 0.018) for an SBP ratio (extubation/rest) ≥1.3 and 4.75 (p = 0.055) for cerebrovascular disorder, suggesting effects of these two items. With simultaneous input into a multivariate model, SBP ratio ≥1.3 had a significant independent association with postoperative SEH (p = 0.021) and cerebrovascular disorder showed a tendency for this association (p = 0.072).

CONCLUSION

The risk for symptomatic epidural hematoma is significant in patients with SBP at extubation that is more than 1.3 times that of SBP at rest.

Neurological outcome after resection of spinal schwannoma

INTRODUCTION

Spinal schwannoma (SS) is the most frequently diagnosed benign spinal tumor, constituting approximately 25 % of all intradural tumors. Aim of our study was to identify factors that potentially affect immediate postoperative neurological outcome, and the rate of functional recovery within 12 months.

METHODS

Screening of our institutional database yielded 90 consecutive patients (mean age 57.1 years, 39 women [43.3 %]) with newly diagnosed SS between March 1997 and October 2018. We pre- and postoperatively reviewed patient charts, surgical reports, radiographic data, use of IOM, duration of symptoms, histopathology, co-morbidities, radiographic extension, surgical strategy, neurological performance (Japanese Orthopedic Association Score [JOA score] and Frankel Grade Classification).

RESULTS

Mean duration of preoperative symptoms was 3.6 ± 1.6 months. Most common symptoms were local pain (n = 77, 85.6 %). Macroscopic complete resection was achieved in 84 patients (93.3 %). During follow-up, complete recovery from local pain was documented for 41 patients (59.7 %), from radiating pain for 41 (69.5 %; p < 0.001). Postoperatively, 25 (27.7 %) patients developed a new neurological deficit (motor deficits n = 3 and sensory deficits n = 23; one patient developed both); after 12 months, however, motor deficits had abated in all patients, and 16 (69.5 %) patients had completely recovered from sensory deficits. Use of intraoperative monitoring (IOM) was a significant predictor for good functional outcome (p < 0.001).

CONCLUSION

Resection of SS accompanied by IOM whenever feasible should be advocated. We achieved a high number of complete resections with a low rate of morbidity. New postoperative motor or sensory deficits had a very high rate of complete recovery within 12 months.

Does the drain placement technique affect the amount of postoperative spinal epidural hematoma after microendoscopic decompressive laminotomy for lumbar spinal stenosis?

OBJECTIVE

To prospectively evaluate with magnetic resonance imaging (MRI), the relationship between the distance from the incision of the drain output location and postoperative spinal epidural hematoma (SEH) in patients performed with microendoscopic decompressive laminotomy (MEDL) for lumbar spinal stenosis.

METHODS

Between January 2016 and June 2018, three different kinds of drain placement techniques, according to the drain output location, were performed to a total of 184 patients after MEDL for single-level spinal stenosis. The location of the drain output was within the incision in group 1, 1 cm lateral of the incision in group 2, and 5 cm lateral of the incision in group 3. At 24 h postoperatively, before removal of the drain, MRI examination was carried out in patients. A specific classification was developed by the authors to measure SEH, and the groups were evaluated by comparison.

RESULTS

The mean postoperative dural sac cross-sectional area was 1.73 cm² (standard deviation (SD): 0.711) in group 1, 1.66 cm² (SD: 0.732) in group 2, and 1.52 cm² in group 3 (SD: 0.841).The mean cross-sectional area of the postoperative hematoma was 1.45 cm² (SD: 1.007) in group 1, 1.57 cm² (SD: 1.053) in group 2, and 2.11 cm² (SD: 1.024) in group 3. Four grades were defined according to the specific classification. According to this classification, grades C and D postoperative hematomas were determined at a statistically significantly higher rate in group 3 patients (drain output 5 cm lateral from the incision) compared to the other groups (p = 0.000). No significant difference was determined between groups 1 and 2 in respect of hematoma classification.

CONCLUSION

In conclusion, it was determined that better drainage was provided in groups 1 and 2, where the drain output location was in the incision or close to it.

Effectiveness of Gelatin-Thrombin Matrix Sealants (Floseal®) on Postoperative Spinal Epidural Hematoma during Single-Level Lumbar Decompression Using Biportal Endoscopic Spine Surgery: Clinical and Magnetic Resonance Image Study

Background

Symptomatic postoperative spinal epidural hematoma (PSEH) is a devastating complication that could develop after lumbar decompression surgery. PSEH can also develop after biportal endoscopic spine surgery (BESS), one of the recently introduced minimally invasive spine surgery techniques. Gelatin-thrombin matrix sealant (GTMS) is commonly used to prevent PSEH. This study aimed at analyzing the clinical and radiological effects of GTMS use during BESS.

Methods

A total of 206 patients with spinal stenosis who underwent decompression by BESS through a posterior interlaminar approach from October 2015 to September 2018 were enrolled in this study. Postoperative magnetic resonance imaging (MRI) was performed in all patients for evaluation of PSEH. Patients in whom GTMS was not used during surgery were assigned to Group A, and those in whom GTMS was used were classified as Group B. In the clinical evaluation, the visual analog scale (VAS) of the leg and back, Oswestry Disability Index (ODI), and modified MacNab criteria were used. The incidence rate and degree of dural compression of PSEH on postoperative MRI were measured.

Results

The average age of the patients was 68.1 ± 11.2 (42–89) years. The overall incidence rate of PSEH was 20.9% (43/206). The incidence rates in Groups A and B were 26.4% and 13.6%, respectively, showing a significant difference (p = 0.023). The VAS-leg and ODI improvement was significantly different depending on the intraoperative use of GTMS. However, there was no statistically significant difference between the two groups in terms of the VAS-back improvement. Groups A and B showed “good” and “excellent” rates according to the modified MacNab criteria in 79.4% and 87.6% of patients, respectively, showing statistically significant difference (p = 0.049). In Group A, two patients underwent revision surgery due to PSEH, while none in Group B had such event.

Conclusion

Intraoperative use of GTMS during BESS may be related to reduction in the occurrence rate of PSEH. Specifically, patients with GTMS appliance showed marked decrease in the occurrence of PSEH and had better clinical outcomes.

Incidence and risk factors of spinal epidural hemorrhage after spine surgery: a cross-sectional retrospective analysis of a national database

BACKGROUND

With increasing number of patients undergoing spine surgery, the spinal epidural hemorrhage (SEH) has become a growing concern. However, current studies on SEH rely on case reports or observations from a single center. Our study attempted to demonstrate the incidence rate and risk factors of SEH using a national dataset.

METHODS

A total of 17,549 spine surgery cases from the Health Insurance Review and Assessment Service National Inpatient Sample of 2014 were analyzed. After evaluating the incidence of SEH based on severe cases requiring reoperation, a univariate comparison was performed. Variables found to be significant were included in a multivariable analysis model to determine the risk factors.

RESULTS

The incidence of SEH was found to be 1.15% in Korean population, and there were no severe SEH cases. Our analysis confirmed the previous findings that lumbar surgery, intraoperative blood loss, prolonged surgical time, high blood pressure, use of nonsteroidal anti-inflammatory drugs, and concurrent bleeding factors are the risk factors of SEH. Anterior approach showed a protective effect. The use of anticoagulant demonstrated no statistical significance.

CONCLUSION

Although severe SEH cases were not detected, the incidence of SEH was similar to that reported in literature. Given that SEH is a rare complication of spine surgery and constitutes an important research area that needs to be studied further, our study makes a meaningful contribution based on a rigorous national level sample for the first time and provides the academic circle and health professionals with a reliable evidence of improved clinical outcomes in such cases.

Drainage after posterior single-level instrumented lumbar fusion: Natural pressure vs negative pressure

Recent findings have shown a trend toward recommending against the routine use of drains in spinal surgery because it carries the risk for potential complications. However, most surgeons still use closed suction drainage to prevent hematoma formation. This study is to compare the clinical outcomes between natural pressure drainage and negative pressure drainage after posterior lumbar interbody fusion.Consecutive 132 patients who underwent spinal fusion in the Third Hospital of Hebei Medical University and met the inclusion criteria were reviewed from January 2018 to January 2019 and divided into negative pressure drainage group and natural pressure drainage group according to different pressure drainage. There were 64 patients who had a negative pressure drainage placed and 68 patients who had a natural pressure drainage placed. Demographics, intraoperative blood loss, operative room time, drainage volume at the 1st postoperative day, total volume of postoperative drainage, the total drainage days, postoperative temperature, and postoperative complications (wound infection, symptomatic hematoma) were compared between the 2 groups.The median drainage volume at the 1st postoperative day in negative pressure group was 204.89 ± 95.19 mL, while in natural pressure group, it was 141.00 ± 52.19 mL (P = .000). The median total volume of postoperative drainage in negative pressure group was 378.06 ± 117.98 mL, while in natural pressure group, it was 249.32 ± 70.74 mL (P = .000). The median total drainage days between natural pressure group and negative pressure group were obviously different (2.93 ± 0.55 vs 3.51 ± 0.71 days, P = .000). There was no difference in patient characteristics, operative data, postoperative temperature, and complications.Natural pressure drainage significantly reduced postoperative drainage volume and indwelling time, but did not increase postoperative complications. Therefore, it may offer an alternative to negative pressure drainage and is as safe and effective as negative pressure drainage.

Investigation of analgesic dose of nalbuphine combined with remifentanil after radical gastrectomy

Clinical analgesic effect of different doses of nalbuphine combined with remifentanil on postoperative gastric cancer patients was explored. One hundred cases of gastric cancer patients treated from December 2014 to December 2016 in the Xiangyang No. 1 People's Hospital were selected and separated into group A and group B. The dose in group A was 0.2 mg/kg of nalbuphine plus 0.2 µg/kg of remifentanil, and 0.3 mg/kg of nalbuphine plus 0.1 µg/kg of remifentanil in group B. Analgesia was performed by self-controlled intravenous injection. The Visual Analogue Scale (VAS) pain scores and the Brinell Comfort Score (BCS) at 2, 6, 12, 24 and 48 h after operation, and the incidence of adverse reactions were compared between the two groups. The VAS scores in group A were higher than those in group B, but the BCS scores in group A were lower (P<0.05). Postoperative patient-controlled intravenous analgesia (PCIA) press times in group A were lower than those in group B (P<0.05); the incidence of adverse reactions such as nausea and vomiting in group A was higher than that in group B (P<0.05). The analgesic effect of intravenous analgesia scheme of 0.3 mg/kg of nalbuphine and 0.1 µg/kg of remifentanil on gastric cancer patients after operation is better than that of 0.2 mg/kg of nalbuphine and 0.2 µg/kg of remifentanil, which reduces the incidence of adverse reactions, has greater security, and can be promoted.

Deep Cervical Artery as a Source of Bleeding in Postoperative Spinal Epidural Hematoma: A Case Report

The source of bleeding in postoperative spinal epidural hematoma (pSEH) is often unclear. We describe a surgical case of pSEH in which the source of bleeding was thought to be the deep cervical artery (DCA). A 67-year-old man underwent C₃ laminectomy, C_4–6 unilateral open door laminoplasty, and C₇ partial laminotomy for cervical spondylotic myelopathy. Intraoperatively, arterial hemorrhage from a distal branch of the right DCA was observed while drilling the lateral end of the C₃ lamina, so electrocoagulation hemostasis was performed. A suction drain was used to obliterate the epidural space, and it was removed 22 h postoperatively. The patient suddenly felt posterior cervical pain 26 h postoperatively. Computed tomography demonstrated a huge epidural hematoma at the C_3–6 level. The hematoma was evacuated 4 h after the onset of symptoms. Active bleeding was not seen intraoperatively. The patient was discharged on postoperative day 13, and no symptoms caused by the epidural hematoma remained. Considering the findings of the first operation, we concluded that a branch of the DCA might have been the source of bleeding in pSEH, and the site of the drain and removal procedure might have been one of the causes of bleeding. It is important to be aware of the DCA as a blood vessel because it requires careful attention when dissecting the semispinalis cervicis or performing operations for hemostasis before wound closure.

Analysis of detailed clinical characteristics of spinal subdural hematoma following lumbar decompression surgery

BACKGROUND

Only a few reports have described symptomatic patients with postoperative spinal subdural hematoma (SSH) for which further surgery may have been required. No report has focused on the detailed clinical characteristics of postoperative SSH, including asymptomatic cases, in a case series. The reasons for this may be that SSH is an implicitly recognized rare entity, and there is no established consensus regarding the significance of performing postoperative magnetic resonance imaging (MRI) for all cases and the time at which to perform it. In this case-controlled retrospective analysis, we attempted to identify a detailed clinical presentation of SSH after open lumbar decompression surgery using MRI taken uniformly at 14 days before hospital discharge.

METHODS

We retrospectively studied 196 patients who underwent routine MRI following open lumbar spinous process-splitting decompression surgery between 2012 and 2016. We assessed the frequency, clinical presentation, and radiological findings of SSH that developed postoperatively. Furthermore, we used a multivariate analysis to identify factors that were postulated to increase the risk of SSH postoperatively.

RESULTS

None of the patients developed serious neurologic deficits, such as paresis or bladder and bowel dysfunction that required emergency evacuation. However, our results showed that postoperative SSHs, including asymptomatic SSHs, developed considerably frequently (43/182 patients, 23.6%). Furthermore, of the 43 patients with SSH, three presented with new postoperative neurologic findings that were strongly suspected to be associated with SSH. Multivariate analysis identified that preoperative hypertension (adjusted odds ratio [aOR]: 2.501, P = 0.018), anticoagulant therapy (aOR: 2.716, P = 0.021), and multilevel procedures (aOR: 2.327, P = 0.034) were significant risk factors of postoperative SSH.

CONCLUSIONS

Spine surgeons should be aware that postoperative SSH is not rare and is a potential cause of recurrent pain or neurologic deterioration perioperatively.

Impact of lumbar hypolordosis on the incidence of symptomatic postoperative spinal epidural hematoma after decompression surgery for lumbar spinal canal stenosis

PURPOSE

Potential associations between radiographic parameters and the incidence of symptomatic postoperative spinal epidural hematoma (PSEH) have not been identified. This study aimed to identify risk factors including radiographic parameters for symptomatic PSEH after posterior decompression surgery for lumbar spinal canal stenosis (LSS).

METHODS

We retrospectively reviewed 1007 consecutive patients who underwent lumbar decompression surgery for lumbar spinal canal stenosis (LSS) at our institution. We identified 35 cases of symptomatic PSEH, defined by clinical symptoms and MRI findings, and selected 3 or 4 age- and sex-matched control subjects for each PSEH subject (124 controls). We compared radiographic parameters and previously reported risk factors between PSEH and control subjects.

RESULTS

Compared to the control group, PSEH patients had significantly higher preoperative systolic (p = .020) and diastolic (p = .048) blood pressure, and more levels of decompression (p = .001). PSEH and control subjects had significant differences in lumbar lordosis (PSEH 24.8° ± 14.6°, control 34.8° ± 14.5°), pelvic tilt (25.1° ± 11.7° vs. 20.8° ± 8.4°), sacral slope (23.4° ± 9.4° vs. 27.6° ± 8.3°), and pelvic incidence minus lumbar lordosis (23.7° ± 15.0° vs. 13.7° ± 14.6°). Multivariate analysis revealed two significant risk factors for PSEH: decompression of two or more levels and lumbar lordosis < 25°.

CONCLUSIONS

Multilevel decompression and hypolordosis are significant risk factors for symptomatic PSEH after decompression surgery for LSS. LSS patients with lumbar hypolordosis or multilevel stenosis should be carefully observed for PSEH after decompression surgery. These slides can be retrieved under Electronic Supplementary Material.

Postoperative Spinal Subdural Lesions Following Lumbar Spine Surgery: Prevalence and Risk Factors

Study Design

Retrospective case–control study

Purpose

To clarify the prevalence and risk factors for spinal subdural lesions (SSDLs) following lumbar spine surgery.

Overview of Literature

Because SSDLs, including arachnoid cyst and subdural hematoma, that develop following spinal surgery are seldom symptomatic and require reoperation, there are few reports on these pathologies. No study has addressed the prevalence and risk factors for SSDLs following lumbar spine surgery.

Methods

We conducted a retrospective analysis of the magnetic resonance (MR) images and medical records of 410 patients who underwent lumbar decompression surgery with or without instrumented fusion for degenerative disorders. SSDLs were classified into three grades: grade 0, no obvious lesion; grade 1, cystic lesion; and grade 2, lesions other than a cyst. Grading was based on the examination of preoperative and postoperative MR images. The prevalence of SSDLs per grade was calculated and risk factors were evaluated using multivariate logistic regression analysis.

Results

Postoperative SSDLs were identified in 123 patients (30.0%), with 50 (12.2%) and 73 (17.8%) patients being classified with grade 1 and 2 SSDLs, respectively. Among these, one patient was symptomatic, requiring hematoma evacuation because of the development of incomplete paraplegia. Bilateral partial laminectomy was a significantly independent risk factor for SSDLs (odds ratio, 1.52; 95% confidence interval, 1.20–1.92; p<0.001). In contrast, a unilateral partial laminectomy was a protective factor (odds ratio, 0.11; 95% confidence interval, 0.03–0.46; p=0.002).

Conclusions

The prevalence rate of grade 1 SSDLs was 30%, with no associated clinical symptoms observed in all but one patient. Bilateral partial laminectomy increases the risk for SSDLs, whereas unilateral partial laminectomy is a protective factor.

Large Compressive Pseudomeningocele Causing Early Major Neurologic Deficit After Spinal Surgery

STUDY DESIGN

Retrospective review.

OBJECTIVES

Large compressive pseudomeningocele causing a major neurologic deficit is a very rare complication that is not well described in the existing literature.

METHODS

Institutional review board consent was obtained to study 2552 consecutive extradural spinal surgical cases performed by a single senior spinal surgeon during a 10-year period. The surgeon's database for the decade was retrospectively reviewed and 3 cases involving postoperative major neurologic deficits caused by large compressive pseudomeningocele were identified.

RESULTS

The incidence of postoperative compressive pseudomeningocele causing major neurologic deficit was 0.12% (3/2552) per decade of spinal surgery with approximately 1.3% of cases incurring incidental durotomy. Average age of the patients was 57 years (range 45-78). One patient had posterior cervical spine surgery, and 2 patients had posterior lumbar surgery. All 3 patients had intraoperative incidental durotomy repaired during their index procedure. Large compressive pseudomeningocele causing major neurologic deficit occurred in the early 2-week postoperative period in all patients and was clearly identified on postoperative magnetic resonance imaging. All 3 patients were treated with emergent decompression and repair of the dural defect. All patients recovered neurologic function after revision surgery.

CONCLUSIONS

Incidental durotomy and repair causing a large compressive pseudomeningocele after spine surgery is a rare and potentially devastating event. Early postoperative magnetic resonance imaging assists in the diagnosis. Emergent decompression combined with revision dural repair surgery may result in improved outcomes. Surgeons should be cognizant of this rare cause of early postoperative major neurologic deficit in patients who had previous dural repair.