Can activated titanium interbody cages accelerate or enhance spinal fusion? a review of the literature and a design for clinical trials.

While spinal interbody cage options have proliferated in the past decade, relatively little work has been done to explore the comparative potential of biomaterial technologies in promoting stable fusion. Innovations such as micro-etching and nano-architectural designs have shown purported benefits in in vitro studies, but lack clinical data describing their optimal implementation. Here, we critically assess the pre-clinical data supportive of various commercially available interbody cage biomaterial, topographical, and structural designs. We describe in detail the osteointegrative and osteoconductive benefits conferred by these modifications with a focus on polyetheretherketone (PEEK) and titanium (Ti) interbody implants. Further, we describe the rationale and design for two randomized controlled trials, which aim to address the paucity of clinical data available by comparing interbody fusion outcomes between either PEEK or activated Ti lumbar interbody cages. Utilizing dual-energy computed tomography (DECT), these studies will evaluate the relative implant-bone integration and fusion rates achieved by either micro-etched Ti or standard PEEK interbody devices. Taken together, greater understanding of the relative osseointegration profile at the implant-bone interface of cages with distinct topographies will be crucial in guiding the rational design of further studies and innovations.

Ischemic Stroke After Treatment of Intraprocedural Thrombosis During Stent-Assisted Coiling and Flow Diversion.

BACKGROUND AND PURPOSE: Intraprocedural thrombosis poses a formidable challenge during neuroendovascular procedures because the risks of aggressive thromboembolic treatment must be balanced against the risk of postprocedural hemorrhage. The aim of this study was to identify predictors of ischemic stroke after intraprocedural thrombosis after stent-assisted coiling and pipeline embolization device placement. METHODS: A retrospective analysis of intracranial aneurysms treated with stent-assisted coiling or pipeline embolization device placement between 2007 and 2016 at 4 major academic institutions was performed to identify procedures that were complicated by intraprocedural thrombosis. RESULTS: Intraprocedural thrombosis occurred in 34 (4.6%) procedures. Postprocedural ischemic stroke and hemorrhage occurred in 20.6% (7/34) and 11.8% (4/34) of procedures complicated by intraprocedural thrombosis, respectively. Current smoking was an independent predictor of ischemic stroke. There was no statistically significant difference in the rate of ischemic stroke or postprocedural hemorrhage with the use of abciximab compared with the use of eptifibatide in treatment of intraprocedural thrombosis. CONCLUSIONS: Current protocols for treatment of intraprocedural thrombosis associated with placement of intra-arterial devices were effective in preventing ischemic stroke in ≈80% of cases. Current smoking was the only independent predictor of ischemic stroke.

Use of Platelet Function Testing Before Pipeline Embolization Device Placement: A Multicenter Cohort Study.

BACKGROUND AND PURPOSE: Thromboembolic complications constitute a significant source of morbidity after neurointerventional procedures. Flow diversion using the pipeline embolization device for the treatment of intracranial aneurysms necessitates the use of dual antiplatelet therapy to reduce this risk. The use of platelet function testing before pipeline embolization device placement remains controversial. METHODS: A retrospective review of prospectively maintained databases at 3 academic institutions was performed from the years 2009 to 2016 to identify patients with intracranial aneurysms treated with pipeline embolization device placement. Clinical and radiographic data were analyzed with emphasis on thromboembolic complications and clopidogrel responsiveness. RESULTS: A total of 402 patients underwent 414 pipeline embolization device procedures for the treatment of 465 intracranial aneurysms. Thromboembolic complications were encountered in 9.2% of procedures and were symptomatic in 5.6%. Clopidogrel nonresponders experienced a significantly higher rate of thromboembolic complications compared with clopidogrel responders (17.4% versus 5.6%). This risk was significantly lower in nonresponders who were switched to ticagrelor when compared with patients who remained on clopidogrel (2.7% versus 24.4%). In patients who remained on clopidogrel, the rate of thromboembolic complications was significantly lower in those who received a clopidogrel boost within 24 hours pre-procedure when compared with those who did not (9.8% versus 51.9%). There was no significant difference in the rate of hemorrhagic complications between groups. CONCLUSIONS: Clopidogrel nonresponders experienced a significantly higher rate of thromboembolic complications when compared with clopidogrel responders. However, this risk seems to be mitigated in nonresponders who were switched to ticagrelor or received a clopidogrel boost within 24 hours pre-procedure.

Does distracting pain justify performing brain computed tomography in multiple traumas with mild head injury?

Traumatic brain injury (TBI) is a significant health concern classified as mild, moderate, and severe. Although the indications to perform brain computed tomography (CT) are clear in moderate and severe cases, there still exists controversy in mild TBI (mTBI). We designed the study to evaluate the significance of distracting pain in patients with mTBI. The study population included patients with mild traumatic brain injury (GCS ≥13). Moderate and high risk factors including age <18 months or ≥60 years, moderate to severe or progressive headache, ≥2 episodes of vomiting, loss of consciousness (LOC), post-traumatic amnesia, seizure or prior antiepileptic use, alcohol intoxication, previous neurosurgical procedures, uncontrolled hypertension, anticoagulant use, presence of focal neurologic deficits, deformities in craniofacial region, and penetrating injuries were excluded. The patients were then grouped based on presence (DP+) or absence (DP-) of another organ fracture with severe pain (based on VAS). The primary outcome was any abnormal findings on brain CT scans; 330 patients were enrolled (184 DP+ and 146 DP-). Overall, two DP+ and one DP- patients had mild cerebral edema in brain CT (p > 0.99). No patients had any neurologic symptoms or signs in follow-up. Our results show that in the absence of any other risk factors, distracting pain from other organs (limbs, pelvis, and non-cervical spine) cannot be regarded as a brain CT indication in patients with mild TBI, as it is never associated with significant intracranial lesions.

Utility of Decremental Triggered Electromyogram for Intraoperative Neuromonitoring to Identify Midline in Posterior Myelotomy for Spinal Cord Intramedullary Lesions: Technical Note of a Novel Method.

BACKGROUND AND IMPORTANCE: Intramedullary spinal cord lesions are eloquent lesions that are surgically resected via posterior midline myelotomy (PMM). This treatment method carries the risk of postoperative neurological deficits. Various intraoperative neuromonitoring techniques have been used to address this concern. Our study aimed to highlight a newly developed monitoring technique (decremental-triggered electromyogram [dtEMG]) as a novel method to identify the spinal cord midline during PMM. CLINICAL PRESENTATION: Seven patients in prone position underwent PMM for an intramedullary lesion using dtEMG for neuromonitoring. dtEMG was used to determine the threshold amplitude (ie, the lowest amplitude to elicit an EMG response) as well as a silent zone, which was determined to be the midline. The age range was 26-73 years. dtEMG detected a silent zone in 6/7 patients. The only patient in whom dtEMG was not useful was a patient with complete paraplegia and sensory loss before surgery. There were no motor evoked or somatosensory evoked potential changes related to PMM in these patients. DISCUSSION: Although the commonly used neuromonitoring techniques, including motor and sensory evoked potentials and free-run electromyograms are of utmost importance in spinal cord surgery, they lack the potential to identify midline in such cases. The currently available tools, including dorsal column mapping, are more cumbersome to use. CONCLUSION: The newly proposed dtEMG technique can safely and efficiently identify the midline when used as an intraoperative neuromonitoring technique in PMM for spinal cord intramedullary lesion resection.

Factors predicting early deterioration in mild brain trauma: a prospective study.

PRIMARY OBJECTIVE: To evaluate risk factors for clinical deterioration in mild traumatic brain injury. RESEARCH DESIGN: Prospective cross-sectional. METHODS AND PROCEDURES: This study evaluated 203 patients with mild traumatic brain injury. A brain computed tomography scan was performed in all patients and they were observed for 6-48 hours. MAIN OUTCOMES AND RESULTS: Among these patients, 2.5% had cerebral contusions and the most common sites for contusions were frontal lobes; 94% of patients had no hematoma in the initial scan, while 3% had subgaleal haematoma, 1.5% had subdural haematoma, 1% showed subarachnoid haemorrhage, 0.5% intracerebral haemorrhage and 0.5% epidural haemorrhage. GCS was 15 in 96.6% and 13-14 in 3.4%. GCS deteriorated in three (1.5%). Presence of coagulopathy, anticoagulant drug use, GCS of 13-14 and increased age predicted further deterioration. Among CT findings, those with midline shift, cerebral contusion and diffuse cerebral oedema deteriorated more. Among different haematoma types, only SDH predicted a worse outcome. CONCLUSIONS: Although deterioration rarely occurs in patients with mild brain injury, those with coagulopathy, anticoagulant drug use, GCS of 13-14, increased age, midline shift, cerebral contusions, diffuse cerebral oedema and SDH were more prone to deterioration.

Effect of Obesity on Surgical Outcomes of Lumbar Microdiscectomy: A Retrospective Analysis of 525 Patients.

INTRODUCTION: Obesity has been implicated in higher rates of intra-operative complications, as well as increased risk for recurrent herniation and re-operation following lumbar microdiscectomy (LMD). However, the current literature is still controversial about whether obesity adversely affects surgical outcomes, especially a higher re-operation rate. In this study, we have compared surgical outcomes such as recurrence of symptoms, recurrence of disc herniation, and re-operation rates in obese and non-obese patients undergoing one segment LMD. METHODS: A retrospective review was conducted on patients undergoing single-level LMD between 2010-2020 at an academic institution. Exclusion criteria included prior lumbar surgery. Outcomes assessed included the presence of persistent radicular pain, imaging evidence of recurrent herniation, and the need for re-operation due to recurrent herniation. RESULTS: A total of 525 patients were included in the study. The mean±SD body mass index (BMI) was 31.2±6.6 (range 16.2-70.0). The mean follow-up was 273.8±445.2 days (range 14-2494). Reherniation occurred in 84 patients (16.0%), and 69 (13.1%) underwent re-operation due to persistent recurrent symptoms. Neither reherniation nor re-operation was significantly associated with BMI (p = 0.47 and 0.95, respectively). Probit analysis did not show any significant association between BMI and the need for re-operation following LMD. CONCLUSION: Obese and non-obese patients experienced similar surgical outcomes. Our results showed that BMI did not adversely affect reherniation or re-operation rate following LMD. If clinically indicated, LMD can be performed in obese patients with disc herniation without a significantly higher re-operation rate.

Effect of Body Mass Index on Fusion Outcome After Short-Segment Posterior Lumbar Fusion.

OBJECTIVE: Obesity is a growing epidemic in the United States. While many adverse effects of obesity on surgical outcome are well studied, a direct correlation among obesity, pseudarthrosis, and adjacent segment pathology is not well defined. In this study we aimed to identify the effect of body mass index (BMI) on pseudarthrosis, adjacent segment pathology (ASP), and reoperation after short-segment (1-3 levels) open posterior lumbar fusion (PLF). METHODS: This is a retrospective study of patients with degenerative spine pathologies who underwent 1-, 2-, or 3-level PLF surgery between 2010 and 2020. The relevant medical and imaging records were reviewed, and the following variables were recorded: age, gender, BMI, smoking status, surgical details, follow-up length, need for reoperation, indication for reoperation (pseudarthrosis or occurrence of ASP). RESULTS: We included363 patients in our study. Twenty-five patients (6.9%) developed pseudarthrosis, 109 (30%) developed ASP, and 104 patients (28.7%) underwent reoperation for either of these reasons. BMI was significantly less in those who developed pseudarthrosis compared with those who did not (28.6 ± 5.5 vs. 31.2 ± 6.2, respectively; P = 0.04). BMI was not significantly different in those who developed ASP or underwent reoperation compared with those who did not (P = 0.06 and 0.08, respectively). Multivariate regression analysis showed none of the variables in the model (age, gender, tobacco use, BMI, and its classes) significantly predicted pseudarthrosis, ASP, or reoperation (P > 0.1 for all variables). CONCLUSIONS: Obese patients undergoing short-segment open PLF have comparable results in terms of pseudarthrosis, ASP, and reoperation.

Does the Number of Interbody Devices Affect the Fusion Outcome in Short-Segment Posterior Lumbar Fusion?

INTRODUCTION: Interbody devices (IBDs) have been shown to improve outcomes when used in posterior lumbar fusion (PLF) surgery; however,the exact extent of their clinical benefit remains a current topic of interest. Our primary objective in this study was to identify whether the use of an IBD at every level of fusion construct would affect fusion outcomes such as adjacent segment pathology (ASP) and pseudarthrosis after one- to three-level PLF surgery. METHODS: This was a single-institution retrospective study. We studied the association of factors such as smoking status, BMI, gender, age, and number of IBDs on the development of ASP and pseudarthrosis. To study the effect of independent variables on ASP and pseudoarthrosis, univariate and multivariate regression analyses were used. RESULTS: The study included 2,061 patients with a history of posterior lumbar fusion who were identified and reviewed. Among these, 363 patients met our inclusion criteria; 247 patients had a minimum follow-up of six months and were finally included in the study. The median follow-up was 30 months. Among the 247 patients, 105 (42.5%) and 24 (9.7%) experienced ASP and pseudarthrosis, respectively. Gender and use of IBD significantly affected the presence of pseudarthrosis (with a higher rate in males and those without any IBDs). Gender, age, BMI, and use of IBDs did not affect ASP. Moreover, using an IBD at each fused level reduced the pseudarthrosis rate significantly compared to when IBDs were not used at all levels (7.3% vs. 27.6%, p <0.001), while there was no significant difference in the rate of ASP (43.6% vs. 34.5%, p = 0.35). CONCLUSIONS: In patients undergoing one- to three-level PLF surgery, the use of an IBD at all levels of the fusion construct significantly reduces the rate of pseudarthrosis. There was no significant correlation between the rates of ASP. Studies with a larger sample size and a longer follow-up time are suggested to validate our results for pseudoarthrosis and ASP. Our results suggest the use of an IBD per fusion level in short-segment PLF surgeries.

The Effect of Interbody Cage Parameters on the Rate of Subsidence in Single-Level Anterior Cervical Discectomy and Fusion (ACDF): A Retrospective Analysis of 98 Patients.

INTRODUCTION: Subsidence is a relatively common consequence after anterior cervical discectomy and fusion (ACDF) surgery. This study aimed to identify the effect of radiological and non-radiological risk factors on subsidence after a single-level ACDF surgery with cage and plate. METHODS: This is a retrospective cohort study of patients who underwent ACDF for radiculopathy or myelopathy at an academic center, University of Kentucky Albert Chandler Hospital, Lexington, Kentucky, United States, between January 2010 and January 2020. Subsidence was defined as the sinking of the interbody cage into the vertebral body at either the superior end plate (SEP) or inferior end plate (IEP) at the ACDF level and was measured manually on lateral standing x-ray. The numerical amount of subsidence was measured in millimeters as the sum of subsidence in the SEP and IEP and was further categorized into subsidence2 and subsidence3 (i.e., presence of subsidence > 2 mm and subsidence > 3 mm, respectively). Multivariate regression analysis was used to assess the effect of variables such as age, gender, body mass index (BMI), tobacco use, follow-up length, cage type, anterior cage height, posterior cage height, anterior cage height ratio, posterior cage height ratio, cage position, cage-end plate interface and cervical alignment on outcomes such as subsidence, subsidence2, and subsidence3. RESULTS: A total of 98 patients were included, of which 46 (47.1%) were male. The mean age of the population was 47.6±8.4 years. Fifty-one patients (52%) experienced subsidence more than 3 mm. Anterior disc height ratio (ADHR) was calculated by dividing the anterior cage height by the anterior disc height (pmADH). The posterior disc height ratio (PDHR) was calculated by dividing the posterior cage height by the posterior disc height (pmPDH). There was no significant correlation between ADHR and PDHR with subsidence, (p=0.93 and 0.56, respectively). Gender, age, BMI, and smoking status did not affect subsidence either. Cage type significantly affected subsidence with a higher subsidence rate in VG2 cages compared to Bengal cages (p=0.05). CONCLUSION:  This study showed that in patients undergoing single-level ACDF with cage and plate, cage size and in particular cage height (if adjusted for individual patients) did not affect subsidence. Other factors such as cage-endplate interface, cage depth in interbody space, and cervical alignment did not significantly affect subsidence either. This might be attributable to the use of an anterior plating system that conducts the force and reduces the stress on the graft-bone interface.

Predicting the Need for Surgery in Patients with Lumbar Disc Herniation: A New Internally Validated Scoring System.

STUDY DESIGN: Prospective study. PURPOSE: To propose a scoring system for predicting the need for surgery in patients with lumbar disc herniation (LDH). OVERVIEW OF LITERATURE: The indications for surgery in patients with LDH are well established. However, the exact timing of surgery is not. According to surgeons, patients with failed conservative treatment who underwent delayed surgery, often after 6 months postsymptom initiation, have poor functional recovery and outcome. METHODS: The current study included patients with symptomatic LDH. Patients with an indication for emergent surgery such as profound or progressive motor deficit, cauda equina syndrome, and diagnoses other than single-level LDH were excluded from the analysis. All patients followed a conservative treatment regimen (a combination of physical therapy, pain medications, and/or spinal epidural steroid injections). Surgery was indicated for patients who continuously experienced pain despite maximal conservative therapy. RESULTS: In total, 134 patients met the inclusion and exclusion criteria. Among them, 108 (80.6%) responded to conservative management, and 26 (19.4%) underwent unilateral laminotomy and microdiscectomy. The symptom duration, disc degeneration grade on magnetic resonance imaging (Pfirrmann disc grade), herniated disc location and type, fragment size, and thecal sac diameter significantly differed between patients who responded to conservative treatment and those requiring surgery. The area under the receiver operating characteristic curve of the scoring system based on the anteroposterior size of the herniated disc fragment and herniated disc location and type was 0.81. CONCLUSIONS: A scoring system based on herniated disc/fragment size, location, and type can be applied to predict the need for surgery in patients with LDH. In the future, this tool can be used to prevent unnecessarily prolonged conservative management (>4-8 weeks).

Spinal Ganglioneuroma: A Systematic Review of the Literature.

OBJECTIVE: Spinal ganglioneuromas (GNs) are rare benign tumors that often manifest as symptoms related to the compression of neural elements. The preferred treatment for affected patients is surgical resection, which typically improves symptoms and accompanies a low likelihood of tumor recurrence. We conducted a systematic review of reports of GNs involving the spinal cord and nerve roots, examining their clinical presentation, surgical management, and outcomes. METHODS: Using the keywords "ganglioneuroma" and "spinal," we conducted a systematic database review of MEDLINE (PubMed), Scopus, and Embase, querying studies reporting cases of spinal GNs. Patients' demographics, location of the tumors, clinical features, and surgical outcomes were extracted from eligible articles. RESULTS: A total of 93 spinal GN cases in 52 case reports/series met our criteria. Data analysis revealed a general male predominance, though thoracic spinal GNs were seen more in females. The mean age of patients with cervical, thoracic, thoracolumbar, and lumbar spinal GNs were 41.28, 27.65, 15.61, and 38.73 years, respectively. Multiple-level GNs were mostly seen in male patients or individuals with neurofibromatosis type 1. In all but 1 case, recurrence and reoperation were not reported in the short-term (months) and long-term (2-10 years) follow-up. CONCLUSIONS: We found unique epidemiologic characteristics for patients with GNs of different spinal regions. The treatment of choice is achieving gross total resection, but given the eloquency of the lesions, achieving decompression via subtotal resection can also be associated with improved outcomes. To date, no global postoperative surveillance protocol exists, considering the low recurrence rate and relevant cost-benefit ratios.

Influence of clinical and radiological parameters on the likelihood of neurological improvement after surgery for degenerative cervical myelopathy.

OBJECTIVE: Degenerative cervical myelopathy (DCM) is routinely treated with surgical decompression, but disparate postoperative outcomes are frequently observed, ranging from complete neurological recovery to persistent decline. Although numerous clinical and radiological factors have been independently associated with failure to improve, the relative impact of these proposed risk factors remains obscure. In this study, the authors assess the combined role of clinical and radiographic parameters in contributing to failure to attain neurological improvement after surgery. METHODS: A consecutive series of patients who underwent surgery for DCM between July 2013 and August 2018 at a single institution was identified from a prospectively maintained database. Retrospective chart review was undertaken to record perioperative clinical and radiographic parameters. Failure to improve on the last follow-up evaluation after surgery, defined as a change in modified Japanese Orthopaedic Association (mJOA) score less than 2, was the primary outcome in univariate and multivariate analyses. RESULTS: The authors included 183 patients in the final cohort. In total, 109 (59.6%) patients improved (i.e., responders with ΔmJOA score ≥ 2) after surgery and 74 (40.4%) were nonresponders with ΔmJOA score < 2. Baseline demographic variables and comorbidity rates were similar, whereas baseline Nurick score was the only clinical variable that differed between responders and nonresponders (2.7 vs 3.0, p = 0.02). In contrast, several preoperative radiographic variables differed between the groups, including presence and degree of cervical kyphosis, number of levels with bidirectional cord compression, presence and number of levels with T2-weighted signal change, intramedullary lesion (IML) length, Torg ratio, and both narrowest spinal canal and cord diameter. On multivariate analysis, preoperative degree of kyphosis at C2-7 (OR 1.19, p = 0.004), number of levels with bidirectional compression (OR 1.83, p = 0.003), and IML length (OR 1.14, p < 0.001) demonstrated the highest predictive power for nonresponse (area under the receiver operating characteristic curve 0.818). A risk factor point system that predicted failure of improvement was derived by incorporating these 3 variables. CONCLUSIONS: When a large spectrum of both clinical and radiographic variables is considered, the degree of cervical kyphosis, number of levels with bidirectional compression, and IML length are the most predictive of nonresponse after surgery for DCM. Assessment of these radiographic factors can help guide surgical decision-making and more appropriately stratify patients in clinical trials.

Intra-arterial injection of acrylic cement as a complication of percutaneous vertebroplasty.

Percutaneous vertebroplasty (PVP) with polymethylmethacrylate (PMMA) is a minimally invasive procedure that provides significant pain relief in a high percentage of patients with osteoporotic fractures. The complication rate of PVP is reported to be below 6%. This case illustrates, for the first time, an arterial PMMA embolus to the aorta and its branches as a complication of PVP.

Middle Meningeal Artery Embolization Versus Conventional Treatment of Chronic Subdural Hematomas.

BACKGROUND: Middle meningeal artery (MMA) embolization is an emerging minimally invasive endovascular technique for chronic subdural hematoma (cSDH). Currently, limited literature exists on its safety and efficacy compared with conventional treatment (open-surgical-evacuation-only). OBJECTIVE: To compare MMA embolization to conventional treatment. METHODS: Retrospective analysis of patients with cSDHs treated with MMA embolization in a single center from 2018 to 2019 was performed. Comparisons were made with a historical conventional treatment cohort from 2006 to 2016. Propensity score matching analysis was used to assemble a balanced group of subjects. RESULTS: A total of 357 conventionally treated cSDH and 45 with MMA embolization were included. After balancing with propensity score matching, a total of 25 pairs of cSDH were analyzed. Comparing the embolization with the conventional treatment group yielded no significant differences in complications (4% vs 4%; P > .99), clinical improvement (82.6% vs 83.3%; P = .95), cSDH recurrence (4.3% vs 21.7%; P = .08), overall re-intervention rates (12% vs 24%; P = .26), modified Rankin scale >2 on last follow-up (17.4% vs 32%; P = .24), as well as mortality (0% vs 12%; P = .09). Radiographic improvement at last follow-up was significantly higher in the open surgery cohort (73.9% vs 95.6%; P = .04). However, there was a trend for lengthier last follow-up for the historical cohort (72 vs 104 d; P = .07). CONCLUSION: There was a trend for lower recurrence and mortality rates in the embolization era cohort. There were significantly higher radiological improvement rates on last follow-up in the surgical only cohort era. There were no significant differences in complications and clinical improvement.

Factors Predictive of Adjacent Segment Disease After Lumbar Spinal Fusion.

OBJECTIVE: Adjacent segment disease (ASD) is a long-term complication of lumbar spinal fusion. This study aims to evaluate demographic and operative factors that influence development of ASD after fusion for lumbar degenerative pathologies. METHODS: A retrospective cohort study was performed on patients undergoing instrumented lumbar fusion for degenerative disorders (spondylolisthesis, stenosis, or intervertebral disk degeneration) with a minimum follow-up of 6 months. RESULTS: Our inclusion criteria were met by 568 patients; 29.4% of patients had developed surgical ASD. Median follow-up was 2.8 years. Multivariate logistic regression analysis showed that decompression of segments outside the fusion construct had higher ASD (odds ratio = 2.6; P < 0.001), and those undergoing fusion for spondylolisthesis had lower ASD (odds ratio = 0.47; P = 0.003). CONCLUSIONS: Results of our study show that the most important surgical factor contributing to ASD is decompression beyond fused levels. Hence caution should be exercised when decompressing spinal segments outside the fusion construct. Conversely, spondylolisthesis patients had the lowest ASD rates in our cohort.

Hydatid Cyst in the Lumbar Paravertebral Muscle: A Case Report.

A hydatid cyst is a zoonotic disease caused by the worm Echinococcus granulosus. In endemic regions, it is a well-known differential diagnosis of cystic lesions, especially in the liver, lungs, brain, and vertebral column. Primary paravertebral muscle involvement, however, is rarely reported. In the current report, we present the case of an 11-year-old girl complaining of back pain with a well-defined single cystic lesion in her lumbar paravertebral multifidus muscle evident in imaging studies. The patient had no concomitant lesion in her systemic evaluation. The cyst was resected totally with its daughter cysts, and the pathology confirmed the diagnosis of a hydatid cyst. Although the paravertebral muscle is an extremely rare site of infection for a hydatid cyst, it should be kept in mind in mass lesions with a cystic nature.

Safety and Efficacy of the VariLift-C® Cervical Standalone Interbody Fusion Device with Emphasis on Multiple-level and Prior Fusion Cases.

Introduction The VariLift-C® is a stand-alone, expandable, cervical interbody fusion device, not requiring the addition of anterior plating. Because of the access and placement technique, as well as not needing a plate, the device could potentially be used preferentially for patients with prior anterior fusions or for multiple, non-contiguous vertebral segments. Methods A retrospective chart review was conducted and all cases of anterior cervical discectomy and fusion (ACDF) using VariLift-C® implants by a single surgeon were included. Patient baseline and operative characteristics were collected, and their follow-up notes were searched for outcomes. Descriptive statistics are provided. Results Seventy-one patients were included in this study, 14 of which had had a prior fusion, and 32 underwent a multilevel ACDF. A total of 108 cervical levels were fused. Mean age (± SD) at surgery was 50.3 ± 11.4 years and mean (± SD) follow-up was 6.5 ± 10.7 months. There were 39 single-level, 27 two-level and five three-level fusions. Four cases (5.6%) underwent multilevel re-operations. Thirty-three patients (80.3%) reported substantial improvement in their symptoms on follow-up, 19 of whom (26.8%) had no residual symptoms. Only two patients (2.8%) reported a worsened condition after surgery. There were 10 cases (12.8%) of postoperative neurologic deficit, one case of dysphagia and three cases of vocal cord paresis. Conclusions These results display the use of VariLift-C® for symptomatic cervical degenerative disorders, with a focus on fusion extension or multiple-segment ACDF procedures. Our experience with favorable self-reported outcomes and low complication rates showcases the safety and efficacy of the VariLift-C® device for ACDF.

Factors Predicting the Need for Surgery of the Opposite Side After Unilateral Evacuation of Bilateral Chronic Subdural Hematomas.

BACKGROUND: Patients with bilateral chronic subdural hematoma (bCSDH) undergo unilateral evacuation for the large or symptomatic side because the contralateral hematoma is either small or asymptomatic. However, the contralateral hematoma may subsequently grow and require evacuation. OBJECTIVE: To characterize factors that predict contralateral hematoma growth and need for evacuation. METHODS: A retrospective study on 128 surgically treated bCSDHs. RESULTS: Fifty-one and 77 were bilaterally and unilaterally evacuated, respectively. Glasgow Coma Scale was lower and midline shift was higher in those evacuated unilaterally compared to those evacuated bilaterally. Hematoma size was a significant determinant of decision for unilateral vs bilateral evacuation. The contralateral side needed evacuation at a later stage in 7 cases (9.1%). There was no significant difference in terms of reoperation rate between those evacuated unilaterally and bilaterally. Greater contralateral hematoma thickness on the first postoperative day computed tomography (CT) and more postoperative midline shift reversal had higher rates of operation in the opposite side. There was no difference between the daily pace of hematoma decrease in the operated and nonoperated sides (0.7% decrease per day vs 0.9% for the operated and nonoperated sides, respectively). CONCLUSION: Results of this study show that most bCSDHs evacuated unilaterally do not experience growth in the nonoperated side and unilateral evacuation results in hematoma resolution for both sides in most cases. Hematoma thickness on the opposite side on the first postoperative day CT and amount of midline shift reversal after surgery are the most important factors predicting the need for surgery on the opposite side.

Factors influencing the presence of hemiparesis in chronic subdural hematoma.

OBJECTIVE: Chronic subdural hematoma (CSDH) has a variety of clinical presentations, including hemiparesis. Hemiparesis is of the utmost importance because it is one of the major indications for surgical intervention and influences outcome. In the current study, the authors intended to identify factors influencing the presence of hemiparesis in CSDH patients and to determine the threshold value of hematoma thickness and midline shift for development of hemiparesis. METHODS: The authors retrospectively reviewed 325 patients (266 with unilateral and 59 with bilateral hematomas) with CSDH who underwent surgical evacuation, regardless of presence or absence of hemiparesis. RESULTS: In univariate analysis, hematoma loculation, age, hematoma maximal thickness, and midline shift were significantly associated with hemiparesis. Moreover, patients with unilateral hematomas had a higher rate of hemiparesis than patients with bilateral hematomas. Sex, trauma history, anticoagulant and antiplatelet drug use, presence of comorbidities, Glasgow Coma Scale score, hematoma density characteristics on CT scan, and hematoma signal intensity on T1- and T2-weighted MRI were not associated with hemiparesis. In multivariate analysis, the presence of loculation and hematoma laterality (unilateral vs bilateral) influenced hemiparesis. For unilateral hematomas, maximal hematoma thickness of 19.8 mm and midline shift of 6.4 mm were associated with a 50% probability of hemiparesis. For bilateral hematomas, 29.0 mm of maximal hematoma thickness and 6.8 mm of shift were associated with a 50% probability of hemiparesis. CONCLUSIONS: Presence of loculations, unilateral hematomas, older patient age, hematoma maximal thickness, and midline shift were associated with a higher rate of hemiparesis in CSDH patients. Moreover, 19.8 mm of hematoma thickness and 6.4 mm of midline shift were associated with a 50% probability of hemiparesis in patients with unilateral hematomas.