Surgical site infection rates in open versus endoscopic lumbar spinal decompression surgery: A retrospective cohort study.

Background: Lumbar decompression is a commonly performed procedure for the operative management of several degenerative lumbar spinal pathologies. Although open approaches are considered the traditional method, endoscopic techniques represent a relatively novel, less-invasive option to achieve neural element decompression. Here within, we examine if the use of endoscopic techniques decreases the risk of post operative infections. Methods: We performed a retrospective cohort analysis to directly compare patients who underwent either open or endoscopic lumbar decompression at a single institution. Rates of postoperative outcomes such as surgical site infection, hospital length of stay, estimated blood loss, and others were compared between the two treatment groups. A multivariate logistic regression model was constructed using patient comorbidities and procedural characteristics to identify the risk factors for surgical site infection. Results: 150 patients were identified as undergoing lumbar spine decompression surgeries that met inclusion criteria for the study, of whom 108 (72.0%) underwent open and 61 (28.0%) underwent endoscopic approaches. Unpaired analysis revealed positive associations between operative duration, estimated blood loss, drain placement rates. Multivariate logistic regression did not reveal an association between surgical approach (open versus endoscopic) and the development of surgical site infection. Conclusions: Surgical site infections following endoscopic lumbar spine decompression are relatively uncommon, however, after adjusting for baseline differences between patient populations, surgical approach does not independently predict the development of postoperative infection.

Radiographic Outcomes Following Various Treatment Options of Thoracolumbar Burst Fractures.

BACKGROUND: Thoracolumbar burst fractures include a spectrum of treatment options ranging from conservative management to multilevel fusion with or without corpectomy. Given the variability of treatment options, consideration of radiographic outcomes with different treatment modalities should be a critical consideration in management. METHODS: A retrospective review was conducted evaluating all patients presenting with spine fractures over a 7-year period. Inclusion criteria were limited to adults with acute, traumatic burst fractures of the thoracolumbar joint levels T11-L2. Patients were categorized by nonoperative management, short-segment fusion, multilevel fusion without anterior column reconstruction, and corpectomy. Radiographic information collected included kyphotic angle (KA), Cobb angle (CA), and Gardner angle (GA). RESULTS: In total, 117 patients (70.5%) were successfully treated nonoperatively, 4 (2.4%) underwent short-segment fusion, 28 (16.9%) underwent multilevel fusion, and 12 (7.2%) underwent corpectomy. All nonoperative patients demonstrated significantly worse kyphosis at 1-year follow-up as measured by KA, CA, and GA (P < 0.001). Patients undergoing corpectomy had the largest improvement in kyphosis with an average improvement of 14.1° on KA, 8.1° on CA, and 11.0° on GA (P < 0.001, P = 0.098, and P = 0.004, respectively). In comparison, patients undergoing multilevel fusion showed an average improvement of 2.6°, 2.7°, and 3.3° of correction on GA, CA, and KA, respectively (P > 0.05). CONCLUSIONS: Nonoperative and short-segment fusion burst fracture patients demonstrated significantly worse kyphosis at 1-year follow-up. Patients undergoing corpectomy demonstrated a superior improvement in kyphotic correction compared with those undergoing multilevel fusion and short-segment fusion.

Outcomes following conservative treatment of extension fractures in the setting of diffuse idiopathic skeletal hyperostosis: is external orthosis alone a reasonable option?

OBJECTIVE: Extension fractures in the setting of diffuse idiopathic skeletal hyperostosis (DISH) represent highly unstable injuries. As a result, these fractures are most frequently treated with immediate surgical fixation to limit any potential risk of associated neurological injury. Although this represents the standard of care, patients with significant comorbidities, advanced age, or medical instability may not be surgical candidates. In this paper, the authors evaluated a series of patients with extension DISH fractures who were treated with orthosis alone and evaluated their outcomes. METHODS: A retrospective review from 2015 to 2022 was conducted at a large level 1 trauma center. Patients with extension-type DISH fractures without neurological deficits were identified. All patients were treated conservatively with orthosis alone. Baseline patient characteristics and adverse outcomes are reported. RESULTS: Twenty-seven patients were identified as presenting with extension fractures associated with DISH without neurological deficit. Of these, 22 patients had complete follow-up on final chart review. Of these 22 patients, 21 (95.5%) were treated successfully with external orthosis. One patient (4.5%) who was noncompliant with the brace had an acute spinal cord injury 1 month after presentation, requiring immediate surgical fixation and decompression. No other complications, including skin breakdown or pressure ulcers related to bracing, were reported. CONCLUSIONS: Treatment of extension-type DISH fractures may be a reasonable option for patients who are not candidates for safe surgical intervention; however, a risk of neurological injury secondary to delayed instability remains, particularly if patients are noncompliant with the bracing regimen. This risk should be balanced against the high complication rate and potential mortality associated with surgical intervention in this patient population.

Evaluation of Endoscopic Versus Open Lumbar Discectomy: A Multi-Center Retrospective Review Utilizing the American College of Surgeons' National Surgical Quality Improvement Program (ACS-NSQIP) Database.

INTRODUCTION: Endoscopic techniques in spine surgery continue to gain popularity due to their potential for decreased blood loss and post-operative pain. However, limited studies have evaluated these techniques within the United States. Additionally, given the limited number of practitioners with experience in endoscopy, most current studies are limited by a lack of heterogeneity. METHODS: The American College of Surgeons' National Surgical Quality Improvement Program (ACS-NSQIP) database was queried to evaluate the effect of endoscopic surgery on adverse events. Current Procedural Terminology (CPT) codes for open discectomy were compared with the relevant CPT codes for endoscopic lumbar discectomy. Baseline patient characteristics and adverse outcomes were then compared.  Results: A total of 38,497 single-level lumbar discectomies were identified and included. Of these, 175 patients undergoing endoscopic discectomy were compared with 38,322 patients undergoing open discectomy. Endoscopic discectomy demonstrated a shorter operative time of 88.6 minutes than 92.1 minutes in the open group. However, this was not significant (p=0.08). Patients in the endoscopic group demonstrated a shorter total length of stay of 0.81 days vs 1.15 days (p=0.014). Total adverse events were lower in the endoscopic group at 0.6% vs 3.4% in the open group (p=0.03). CONCLUSION:  Endoscopic discectomy demonstrated a significantly lower rate of adverse events and shorter total length of stay than open discectomy. Further research is necessary over time to evaluate larger patient populations as this technology is more rapidly incorporated.

Radiographic Outcomes of Thoracolumbar AOSpine A3 and A4 Fractures Treated With External Bracing.

Background The treatment of AOSpine A3 and A4 fractures is controversial with no consensus regarding their management in the absence of neurologic deficits. While conservative management with spinal orthosis is a reasonable treatment option, it is believed to run the risk of progressive segmental kyphosis. Methodology A retrospective chart review was conducted of all patients undergoing treatment for thoracolumbar burst fractures from T11 to L2. Patients treated with conservative management with lumbar orthosis were included. Upright radiographs at the time of presentation and the one-year follow-up were compared. Results In total, 112 patients were evaluated as being treated with thoracolumbar orthosis. Of these, 61 patients presented with A3 fractures compared with 51 who presented with A4 fractures. Of these, two patients in each group failed conservative management and required surgical intervention. At the one-year follow-up, A3 fractures demonstrated an average change in Cobb angle of 4.1 degrees compared with 6.1 degrees in A4 fractures (p = 0.021). In addition, A4 fractures demonstrated a significantly worse kyphotic angle and Gardner angle at the one-year follow-up (p = 0.05 and p = 0.026, respectively). Conclusions A3 and A4 fractures can be safely treated with orthosis with overall low rates for failure; however, A4 fractures result in significantly worse segmental kyphosis at the one-year follow-up.

Endotracheal Tube Electrode Neuromonitoring for Placement of Vagal Nerve Stimulation for Epilepsy: Intraoperative Stimulation Thresholds.

Vagal nerve stimulators (VNS) are indicated as a palliative treatment for medically refractory epilepsy. The vagus nerve may have a variable position within the carotid sheath and may be confused with a prominent ansa cervicalis. The objective of this study was to describe an intraoperative neuromonitoring technique for VNS placement and provide stimulation thresholds that may aid in the creation of stimulation protocols. A retrospective study was performed assessing 40 patients undergoing intraoperative vocal cord monitoring during vagal nerve stimulator placement surgery. Endotracheal electrodes were utilized to record vocal cord activity at various surgical time points. The stimulation thresholds were tested at the time of opening of the carotid sheath (mean 0.35 mA [range 0.08-1.00]), after full and circumferential dissection of the vagus nerve (0.34 mA [0.10-0.90]), after tenting of the vagus nerve in preparation for placement of the electrode (0.22 mA [0.06-1.20]), and after electrode placement (0.26 mA [0.05-1.20]). The vagus nerve was identified in all patients; it was located behind the common carotid artery (CCA) in two patients, on top of the internal jugular vein (IJV) in one patient, and in the typical location between the CCA and IJV in the remainder of patients. The average size of the vagus nerve was 2.9 mm [1.5-5.0]. Intraoperative vagus nerve stimulation represents a safe adjunctive tool that can help localize the nerve, particularly in the setting of varying anatomy or hazardous dissections. It may help reduce the potential for vagal trunk damage or electrode misplacement and potentially improve clinical outcomes.

Predictors of 30-Day Readmission Following Cervical Laminoplasty in 3,085 Patients: An American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) Database Study.

Background Cervical laminoplasty is a surgical alternative to laminectomy and fusion for treating multi-level cervical spondylotic myelopathy. There is limited evidence evaluating readmission incidence and risk factors following cervical laminoplasty. Here, we provide a retrospective review evaluating preoperative risk for 30-day readmission following cervical laminoplasty. Methodology The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was used to identify patients undergoing laminoplasty as defined by Current Procedural Terminology codes 63050 and 63051. Patients were then categorized based on whether 30-day readmission occurred, and preoperative risk factors were examined. Continuous and categorical variables were analyzed using Student's t-test or Fisher's exact test. Multivariate regression analysis was performed for each variable, with p-values of <0.05 considered significant. Results In total, 3,085 patients were identified as undergoing posterior cervical laminoplasty. Of these, 2,938 patients did not require readmission, and 147 patients were readmitted, representing a 4.77% 30-day readmission rate. For all patients, sepsis (odds ratio (OR) = 5.58, p = 0.03), dialysis (OR = 3.46, p = 0.01), American Society of Anesthesiologists class >2 (OR = 1.69, p = 0.011), and hypertension (OR = 1.51, p = 0.04) were predictive of readmission. A subgroup analysis was performed for all geriatric patients (aged >65). In total, 1,353 patients were identified, of whom 76 were readmitted, demonstrating a readmission rate of 5.62%. For the elderly patients, hypertension (OR = 1.98, confidence interval (CI) = 1.04-3.75, p = 0.04) and independent status (OR = 0.39, CI = 0.21-0.74, p = 0.004) were predictive of readmission. Conclusions Assessment of predictors for readmission is important for patient education and setting appropriate clinical expectations for surgeons and providers. Preoperative hypertension, dialysis, and sepsis were risk factors for 30-day readmission following cervical laminoplasty, with functional status being a unique risk factor for elderly patients.

Traumatic vertebral artery injuries in the geriatric population: a retrospective cohort study.

OBJECTIVE: Traumatic vertebral artery injuries (TVAIs) are a common finding in cervical spine trauma and can predispose patients to posterior circulation infarction. While extensive research has been conducted regarding the management and criteria for imaging in patients with suspected blunt vascular injury, little research has been conducted highlighting these injuries in the geriatric population. METHODS: The authors performed a retrospective review of all patients evaluated at a level 1 trauma center and found to have TVAIs between January 1, 2010, and January 1, 2018. Biometric, clinical, and imaging data were obtained from a trauma registry database. Patients were divided into 2 groups on the basis of age, a geriatric group (age ≥ 65 years) and an adult group (age 18 to < 65 years). Variables evaluated included type of trauma, mortality, Injury Severity Score (ISS), and ICU length of stay. The Student t-test was used for continuous variables, and Pearson's chi-square test was used for categorical variables. RESULTS: Of the 2698 of patients identified with traumatic cervical spine injuries, 103 patients demonstrated evidence of TVAI. Of these patients, 69 were < 65 and 34 were ≥ 65 years old at the time of their trauma. There was no difference in the incidence of TVAIs between the 2 groups. The ICU length of stay (4.71 vs 4.32 days, p > 0.05), hospital length of stay (10.71 vs 10.72 days, p > 0.05), and the ISS (21.50 vs 21.32, p > 0.05) did not differ significantly between the 2 groups. Mortality was significantly higher in the geriatric group, occurring in 9 of 34 patients (26.5%) compared with only 3 of 69 patients (4.4%) in the adult group (p < 0.001). Ground-level falls were the most common inciting event in the geriatric group (44% vs 14.5%, p < 0.001), whereas motor vehicle accidents were the most common etiology in the younger population (72.5% vs 38.2%, p < 0.001). Incidence of ischemic stroke did not vary significantly between the 2 groups (p > 0.05). CONCLUSIONS: TVAI in the older adult population is associated with a significantly greater risk of mortality than in the younger adult population, despite the 2 groups having similar ISSs. Additionally, low-velocity mechanisms of injury, such as ground-level falls, are a greater risk factor for acquired TVAI in older adults than in younger adults, in whom it is a significantly less common etiology.

Surgical Practice in Traumatic Spinal Fracture Treatment with Regard to the Subaxial Cervical Injury Classification and Severity and the Thoracolumbar Injury Classification and Severity Systems: A Review of 58 Patients at the University of Wisconsin.

OBJECTIVES: Spine surgeons at a Level 1 Trauma Center have observed a high incidence of spine and spinal cord injuries owing to falls from tree stands. These injuries have been retrospectively reviewed in the context of the Thoracolumbar Injury Classification and Severity (TLICS) and the Subaxial Cervical Injury Classification and Severity (SLICS) classification systems to assess inter-user reliability and validity. We hypothesize that the inter-rater reliability will be similar between neuroradiology and neurosurgery raters and validity of the scoring system will be maintained at our institution. METHODS: The University of Wisconsin Hospital and Clinics' trauma database was reviewed for tree stand-related injuries from 1999 to 2013, with a focus on patients suffering from spine and spinal cord injuries. The TLICS and SLICS scores were then independently determined for these injuries by a neurosurgeon and a neuroradiologist. RESULTS: When cases were grouped by management recommendation (operative, equivocal, and nonoperative) reviewer agreement was 12/15 (80%) of SLICS and 38/52 (73%) of TLICS scores. Operative SLICS positive predictive value reached 100%, however, with a wide confidence interval. Conversely, the SLICS negative predictive value was poor at 54%-60%, with frequent operative treatment for patients assigned nonoperative scores. TLICS scores reached 77.8% and 93.3% positive predictive value per reviewer, whereas negative predictive values reached 93.9% and 89.2%, respectively. CONCLUSIONS: The TLICS and SLICS systems provide good-to-excellent inter-rater reliability. SLICS validity was poor, whereas TLICS was reasonable for nonoperative cases and moderate for operative cases. Systems such as the TLICS and the SLICS may be best applied in the educational setting to confirm the fracture morphology and presence or absence of ligamentous injury between surgeons and radiologists.

Anatomical differences in patients with lumbosacral transitional vertebrae and implications for minimally invasive spine surgery.

OBJECTIVE The objective of this study was to investigate the neurovascular and anatomical differences in patients with lumbosacral transitional vertebrae (LSTV) and the associated risk of neurovascular injury in minimally invasive spine surgery. METHODS The authors performed a retrospective study of CT and MR images of the lumbar spine obtained at their institution between 2010 and 2014. The following characteristics were evaluated: level of the iliac crest in relation to the L4-5 disc space, union level of the iliac veins and arteries in relation to the L4-5 disc space, distribution of the iliac veins and inferior vena cava according to the different Moro zones (A, I, II, III, IV, P) at the L4-5 disc space, and the location of the psoas muscle at the L4-5 disc space. The findings were compared with findings on images obtained in 28 age- and sex-matched patients without LSTV who underwent imaging studies during the same time period. RESULTS Twenty-eight patients (12 male, 16 female) with LSTV and the required imaging studies were identified; 28 age- and sex-matched patients who had undergone CT and MRI studies of the thoracic and lumbar spine imaging but did not have LSTV were selected for comparison (control group). The mean ages of the patients in the LSTV group and the control group were 52 and 49 years, respectively. The iliac crest was located at a mean distance of 12 mm above the L4-5 disc space in the LSTV group and 4 mm below the L4-5 disc space in the controls. The iliac vein union was located at a mean distance of 8 mm above the L4-5 disc space in the LSTV group and 2.7 mm below the L4-5 disc space in the controls. The iliac artery bifurcation was located at a mean distance of 23 mm above the L4-5 disc space in the LSTV group and 11 mm below the L4-5 disc space in controls. In patients with LSTV, the distribution of iliac vein locations was as follows: Zone A, 7.1%; Zone I only, 78.6%; Zone I encroaching into Zone II, 7.1%; and Zone II only, 7.1%. In the control group, the distribution was as follows: Zone A only, 17.9%; Zone A encroaching into Zone I, 75%; and Zone I only, 7.1%. There were no iliac vessels in Zone II in the control group. The psoas muscle was found to be rising away laterally and anteriorly from the vertebral body more often in patients with LSTV, resulting in the iliac veins being found in the "safe zone" only 14% of the time, greatly increasing the risk of vascular injury. CONCLUSIONS In patients with LSTV, the iliac crest is more likely to be above the L4-5 disc space, which increases the technical challenges of a lateral approach. The location of the psoas muscle rising away laterally and ventrally in patients with LSTV compared with controls and with the union of the iliac veins occurring more often above the L4-5 disc space increases the risk for iatrogenic vascular injury at the L4-5 level in this patient population.

Giant calvarial intraosseous angiolipoma: a case report and review of the literature.

Intraosseous angiolipomas are very rare tumors occurring most commonly in the ribs and mandible. Only two cases with intracranial involvement have been reported in the literature. We report a case of a giant calvarial angiolipoma and its surgical treatment in a 30-year-old female who presented with a slowly expanding skull mass and discuss relevant radiological, histological and surgical findings.

Adipose-derived stem cells as therapeutic delivery vehicles of an oncolytic virus for glioblastoma.

Glioblastoma multiforme (GBM) accounts for the majority of primary malignant brain tumors and remains virtually incurable despite extensive surgical resection, radiotherapy, and chemotherapy. Treatment difficulty is due to its exceptional infiltrative nature and proclivity to integrate into normal brain tissue. Long-term survivors are rare, and median survival for patients is about 1 year. Use of adult stem cells as cellular delivery vehicles for anticancer agents is a novel attractive therapeutic strategy. We hypothesized that adipose-derived stem cells (ADSCs) possess the ability to home and deliver myxoma virus to glioma cells and experimental gliomas. We infected ADSCs with vMyxgfp and found them to be permissive for myxoma virus replication. ADSCs supported single and multiple rounds of replication leading to productive infection. Further, we observed no significant impact on ADSC viability. We cocultured fluorescently labeled GBM cells with myxoma virus-infected ADSCs in three-dimensional assay and observed successful cross infection and concomitant cell death almost exclusively in GBM cells. In vivo orthotopic studies injected with vMyxgfp-ADSCs intracranially away from the tumor demonstrated that myxoma virus was delivered by ADSCs resulting in significant survival increase. Our data suggest that ADSCs are promising new carriers of oncolytic viruses, specifically myxoma virus, to brain tumors.

Impact of chronic nicotine on the development and maintenance of neuropathic hypersensitivity in the rat.

RATIONALE: Clinical data support a correlation between smoking and the incidence and severity of some chronic pain conditions. However, the impact of nicotine on neuropathic pain has been largely ignored in the laboratory setting. OBJECTIVES: The purpose of these studies was to determine if chronic nicotine would alter mechanical hypersensitivity after spinal nerve ligation. MATERIALS AND METHODS: Rats were implanted with osmotic mini pumps to administer either saline or nicotine (4, 10, or 24 mg/kg/day) for 7 or 21 days. On day 7 of saline/nicotine administration, rats receiving 24 mg/kg/day nicotine underwent spinal nerve ligation. Mechanical thresholds to pressure were measured across nicotine exposure and spinal cords were collected on days 7 or 21. Spinal cord slices were immunostained for phosphorylation of cAMP response element binding protein (pCREB), to determine general neuronal activity, and for cleaved caspase-3, as a marker for apoptosis. RESULTS: Chronic nicotine produced a dose-dependent and stable mechanical hypersensitivity, which could be blocked with the alpha4beta2-selective antagonist, dihydro-beta-erythroidine (DHbetaE). Spinal nerve ligation also produced a stable mechanical hypersensitivity, which was exacerbated in the presence of chronic nicotine. Differences in mechanical sensitivity were reflected in spinal pCREB, which was highly correlated with the degree of mechanical hypersensitivity. Chronic nicotine also altered the number of pro-apoptotic cells in the spinal cord as measured by cleaved caspase-3. CONCLUSIONS: These findings demonstrate that chronic nicotine produces a stable, long-lasting, mechanical hypersensitivity that exacerbates mechanical sensitivity resulting from peripheral nerve injury. The mechanism of this may involve an increase in spinal neuronal activity and apoptosis.