A Multicenter Allelic Analysis of Diffuse Idiopathic Skeletal Hyperostosis: Nature Versus Nurture?

BACKGROUND: Diffuse idiopathic skeletal hyperostosis (DISH) is an incompletely defined disease process with no known unifying pathophysiological mechanism. OBJECTIVE: To our knowledge, no genetic studies have been performed in a North American population. To summarize genetic findings from previous studies and to comprehensively test for these associations in a novel and diverse, multi-institutional population. METHODS: Cross-sectional, single nucleotide polymorphism (SNP) analysis was performed in 55 of 121 enrolled patients with DISH. Baseline demographic data were available on 100 patients. Based on allele selection from previous studies and related disease conditions, sequencing was performed on COL11A2, COL6A6, fibroblast growth factor 2 gene, LEMD3, TGFB1, and TLR1 genes and compared with global haplotype rates. RESULTS: Consistent with previous studies, older age (mean 71 years), male sex predominance (80%), a high frequency of type 2 diabetes (54%), and renal disease (17%) were observed. Unique findings included high rates of tobacco use (11% currently smoking, 55% former smoker), a higher predominance of cervical DISH (70%) relative to other locations (30%), and an especially high rate of type 2 diabetes in patients with DISH and ossification of the posterior longitudinal ligament (100%) relative to DISH alone (100% vs 47%, P < .001). Compared with global allele rates, we found higher rates of SNPs in 5 of 9 tested genes ( P < .05). CONCLUSION: We identified 5 SNPs in patients with DISH that occurred more frequently than a global reference. We also identified novel environmental associations. We hypothesize that DISH represents a heterogeneous condition with both multiple genetic and environmental influences.

Intervertebral kinematics during neck motion 6.5 years after fusion and artificial disc replacement.

BACKGROUND: Arthroplasty with artificial disc replacement for surgical treatment of cervical spine degeneration was introduced with the notion that motion-preserving approaches would prevent development of adjacent segment disease. Though clinical outcomes favor arthroplasty over the commonly used anterior cervical discectomy with fusion approach, clinical studies confirming the biomechanical basis of these results are lacking. The aim of this study was to compare intervertebral kinematics between arthroplasty and fusion patients 6.5 years post-surgery during physiological motion of the neck. METHODS: Using a biplane dynamic X-ray system, computed tomography imaging and model based tracking algorithms, three dimensional intervertebral kinematics were measured during neck axial rotation and extension in 14 patients treated for cervical radiculopathy with fusion (n = 8) or arthroplasty (n = 6). The measurements were performed at 2-year (baseline) and 6.5 year post-surgical time points, with the main interest being in the interaction between surgery types and time points. 3 translations and 3 rotations were investigated for the index (C5C6), and upper- (C4C5) and lower adjacent levels (C6C7). FINDINGS: Surgery-time interaction was significant for axial rotation (P < 0.04) and flexion-extension rotation (P < 0.005) in C4C5 during neck axial rotation, left-right translation (P < 0.04) in C5C6 and anterior-posterior translation in C6C7 (P < 0.04) during neck extension. In contrast with the expectations, axial rotation and flexion-extension decreased in C4C5 during neck rotation and anterior-posterior translation decreased in C6C7 during neck extension for fusion. INTERPRETATION: The findings do not support the notion that adjacent segment motion increases after fusion.

Dynamic foraminal dimensions during neck motion 6.5 years after fusion and artificial disc replacement.

OBJECTIVE: To compare changes in foraminal motion at two time points post-surgery between artificial disc replacement (ADR) and anterior cervical discectomy and fusion (ACDF). METHODS: Eight ACDF and 6 ADR patients (all single-level C5-6) were tested at 2 years (T1) and 6.5 years (T2) post-surgery. The minimum foraminal height (FH.Min) and width (FW.Min) achieved during neck axial rotation and extension, and the range of these dimensions during motion (FH.Rn and FW.Rn, respectively) were measured using a biplane dynamic x-ray system, CT imaging and model-based tracking while patients performed neck axial rotation and extension tasks. Two-way mixed ANOVA was employed for analysis. RESULTS: In neck extension, significant interactions were found between year post-surgery and type of surgery for FW.Rn at C5-6 (p<0.006) and C6-7 (p<0.005), and for FH.Rn at C6-7 (p<0.01). Post-hoc analysis indicated decreases over time in FW.Rn for ACDF (p<0.01) and increases in FH.Rn for ADR (p<0.03) at the C6-7 adjacent level. At index level, FW.Rn was comparable between ACDF and ADR at T1, but was smaller for ACDF than for ADR at T2 (p<0.002). In axial rotation, differences were found between T1 and T2 but did not depend on type of surgery (p>0.7). CONCLUSIONS: Changes were observed in the range of foraminal geometry at adjacent levels from 2 years to 6.5 years post-surgery that were different between ACDF and ADR for neck extension. These changes are contrary to the notion that motion at adjacent levels continue to increase following ACDF as compared to ADR over the long term.

Correlation of neural foraminal motion after surgical treatment of cervical radiculopathy with long-term patient reported outcomes.

BACKGROUND: Post-surgical changes in adjacent segment motion are considered a factor in further development of degeneration and cervical radiculopathy. The objective was to examine the extent of correlations between physiological motion of cervical foramina and long-term patient reported outcomes (PRO). METHODS: Biplane X-ray imaging and CT-based markerless tracking were used to measure 3D static and dynamic dimensions during neck axial rotation and extension from 18 patients treated for C5-6 radiculopathy with fusion or arthroplasty. Minimum foraminal height (FH.Min) and width (FW.Min), and their range (FH.Range and FW.Range) achieved during a motion task were calculated for adjacent levels (C4-5 and C6-7) at 2.0±0.6 years post-surgery. The modified Japanese Orthopedic Association score (mJOAS), the Neck Disability Index (NDI) including the visual analogue scale (VAS) for neck and arm pain, and the EuroQol EQ-5D score were recorded at 6.5±1.1 years post-surgery. The relationships between 6.5-year outcomes and 2-year foraminal motion were examined using regression. RESULTS: Worsening patient-reported outcomes were generally associated with lower values of FW.Min (P<0.05 to P<0.008), the associations being stronger for neck extension (r2 up to 0.43). Dynamic foraminal measurements from the C6-7 level more significantly and consistently correlated with mJOAS, EQ-5D and NDI Arm Pain VAS (r2=0.27 to 0.43; P<0.03 to P<0.008), whereas those from the C4-5 level correlated with NDI Neck Pain VAS (r2=0.33; P<0.02). CONCLUSIONS: Dynamic 3D foraminal dimensions at 2-year post-surgery, notably FW.Min measured in neck extension at adjacent levels, were associated with PRO at 6.5 years post-surgery. These relationships provide insight into the motion related factors in development of pain and loss of function, and may help develop markers or objective outcome measures.

Origins of eponymous instruments in spine surgery.

Every day, spine surgeons call for instruments named after surgical pioneers. Few know the designers or the histories behind their instruments. In this paper the authors provide a historical perspective on the Penfield dissector, Leksell rongeur, Hibbs retractor, Woodson elevator, Kerrison rongeur, McCulloch retractor, Caspar pin retractor system, and Cloward handheld retractor, and a biographical review of their inventors. Historical data were obtained by searching the HathiTrust Digital Library, PubMed, Google Scholar, Google Books, and Google, and personal communications with relatives, colleagues, and foundations of the surgeon-designers. The authors found that the Penfield dissectors filled a need for delicate tools for manipulating the brain and that the Leksell rongeur increased surgical efficiency during war-related laminectomies. Hibbs' retractor facilitated his spine fusion technique. Woodson was both a dentist and a physician whose instrument was adopted by spine surgeons. Kerrison rongeurs were developed in otology to decompress bone near the facial nerve. The McCulloch, Caspar, and Cloward retractors helped improve exposure during the emergence of new techniques, i.e., microdiscectomy and anterior cervical discectomy and fusion. The histories behind these eponymous instruments remind us that innovation sometimes begins in other specialties and demonstrate the role of innovation in improving patient care.

Application of morphometrics as a predictor for survival in female patients with breast cancer spinal metastasis: a retrospective cohort study.

BACKGROUND CONTEXT: The current standard of care for prediction of survival of cancer staging is based on TNM staging. However, for patients with spinal metastasis, who all have identical stage IV disease, identifying accurate prognostic markers of survival would allow better treatment stratification between more aggressive treatment strategies or palliation. Analytical morphometrics enables physicians to quantify patient frailty by measuring lean muscle mass. Morphometrics also predicts survival in patients with lung cancer metastases to the spine. PURPOSE: Our study evaluates whether morphometrics is predictive of survival in patients with breast cancer spinal metastasis. DESIGN: This is an observational retrospective cohort study. PATIENT SAMPLE: This study includes female patients with breast cancer spinal metastases and patients who have undergone stereotactic body radiation therapy. OUTCOME MEASURES: Overall survival was the primary outcome measure. METHODS: Morphometric measurements of the psoas muscle were taken using computed tomography scans of the lumbar spine. We then stratified patients into tertiles based on the psoas muscle area. RESULTS: We identified 118 patients, with a median survival of 104 days (95% confidence interval [CI]=73-157 days). Overall survival was not associated with age, chemotherapy, or number of levels radiated. Patients in the lowest tertile of psoas size had significantly shorter survival compared with the highest tertile (68 days versus 148 days, hazard ratio 1.76 [95% CI=1.08-2.89], p=.024). The shorter survival was also true for the lowest tertile versus the middle tertile (68 days versus 167 days, hazard ratio 1.95 [95% CI=1.19-3.19], p=.007). Kaplan-Meier survival curves were used to visually illustrate the differences in survival between different tertiles. CONCLUSIONS: Morphometric analysis of the psoas muscle size in patients with breast cancer metastases to the spine was effective in identifying patients at risk of shorter survival. Further research is needed to validate these results, as well as to see if these methodologies can be applied to other cancer histologies.

Application of Morphometrics as a Predictor for Survival in Patients with Prostate Cancer Metastasis to the Spine.

BACKGROUND: Surgery for spinal metastases can improve survival but has high morbidity that can potentially diminish benefits. New objective methods of predicting overall survival would be beneficial for surgical decision making. Morphometrics quantifies patient frailty and has been successfully used to predict overall survival in patients with lung cancer spinal metastases. This study evaluated whether morphometrics can predict survival in patients with prostate cancer spinal metastases. METHODS: Using a retrospective registry of patients with spinal metastases who underwent stereotactic body radiation therapy, we identified patients with primary prostate cancer. Morphometric measurements of the psoas muscle were taken from most recent lumbar spine computed tomography. Patients were stratified into lowest, middle, and highest tertiles based on psoas muscle area. Primary outcome measure was overall survival from the date of computed tomography scan. RESULTS: We identified 92 patients. Median survival for all patients was 124 days (95% confidence interval, 98-197 days). Patients in the smallest third for average psoas size had significantly shorter survival compared with patients in the largest third: 117 days versus 302 days (hazard ratio 2.42; 95% confidence interval, 1.32-4.43; P = 0.004). Patients in the middle third for average psoas size also had shorter survival compared with patients in the largest third: 113 days versus 302 days (hazard ratio 2.31; 95% confidence interval, 1.25-4.25; P = 0.007). CONCLUSIONS: In patients with prostate cancer spinal metastases, morphometric analysis of psoas muscle size can identify patients at risk for shorter survival. This technique can aid in surgical decision making by weighing expected survival and fitness versus potential morbidity of intervention.

Assessment of radiographic and clinical outcomes of an articulating expandable interbody cage in minimally invasive transforaminal lumbar interbody fusion for spondylolisthesis.

OBJECTIVE The inability to significantly improve sagittal parameters has been a limitation of minimally invasive surgery for transforaminal lumbar interbody fusion (MIS TLIF). Traditional cages have a limited capacity to restore lordosis. This study evaluates the use of a crescent-shaped articulating expandable cage (Altera) for MIS TLIF. METHODS This is a retrospective review of 1- and 2-level MIS TLIF. Radiographic outcomes included differences in segmental and lumbar lordosis, disc height, evidence of fusion, and any endplate violations. Clinical outcomes included the numeric rating scale for leg and back pain and the Oswestry Disability Index (ODI) for low-back pain. RESULTS Thirty-nine patients underwent single-level MIS TLIF, and 5 underwent 2-level MIS TLIF. The mean age was 63.1 years, with 64% women. On average, spondylolisthesis was corrected by 4.3 mm (preoperative = 6.69 mm, postoperative = 2.39 mm, p < 0.001), the segmental angle was improved by 4.94° (preoperative = 5.63°, postoperative = 10.58°, p < 0.001), and segmental height increased by 3.1 mm (preoperative = 5.09 mm, postoperative = 8.19 mm, p < 0.001). At 90 days after surgery the authors observed the following: a smaller postoperative sagittal vertical axis was associated with larger changes in back pain at 90 days (r = -0.558, p = 0.013); a larger decrease in spondylolisthesis was associated with greater improvements in ODI and back pain scores (r = -0.425, p = 0.043, and r = -0.43, p = 0.031, respectively); and a larger decrease in pelvic tilt (PT) was associated with greater improvements in back pain (r = -0.548, p = 0.043). For the 1-year PROs, the relationship between the change in PT and changes in ODI and numeric rating scale back pain were significant (r = 0.612, p = 0.009, and r = -0.803, p = 0.001, respectively) with larger decreases in PT associated with larger improvements in ODI and back pain. Overall for this study there was a 96% fusion rate. Fourteen patients were noted to have endplate violation on intraoperative fluoroscopy during placement of the cage. Only 3 of these had progression of their subsidence, with an overall subsidence rate of 6% (3 of 49) visible on postoperative CT. CONCLUSIONS The use of this expandable, articulating, lordotic, or hyperlordotic interbody cage for MIS TLIF provides a significant restoration of segmental height and segmental lordosis, with associated improvements in sagittal balance parameters. Patients treated with this technique had acceptable levels of fusion and significant reductions in pain and disability.

Surgical site infection after transoral versus posterior approach for atlantoaxial fusion: a matched-cohort study.

OBJECTIVE In the past, spine surgeons have avoided the transoral approach to the atlantoaxial segment because of concerns for unacceptable patient morbidity. The objective of this study was to measure 30-day postoperative complications, especially surgical site infection (SSI), after transoral versus posterior approach to atlantoaxial fusion. METHODS The source population was provided by the American College of Surgeons National Surgical Quality Improvement Program database, which was queried for all patients who underwent atlantoaxial fusion for degenerative/spondylotic disease and/or trauma between 2005 and 2014. To eliminate bias from unequal sample sizes, patients who underwent the transoral approach were matched with patients who underwent the posterior approach (generally 1:5 ratio) based on age ± 5 years and modified frailty index score (a measure of preoperative comorbidity burden). Because of rare SSI incidence, adjusted odds ratios (ORadj) of SSI were calculated using penalized maximum likelihood estimation. RESULTS A total of 318 patients were included in the study. There were no statistically significant differences between the transoral cohort (n = 56) and the posterior cohort (n = 262) in terms of 30-day postoperative individual complications, including SSI (1.79% vs 1.91%; p = 0.951) and composite complications (10.71% vs 6.87%; p = 0.323). Controlling for sex and smoking, the odds of SSI in the transoral approach were almost equal to the odds in the posterior approach (ORadj 1.17; p = 0.866). While the unplanned reoperation rate of 5.36% after transoral surgery was higher than the 1.53% rate after posterior surgery, the difference approached, but did not reach, statistical significance (p = 0.076). CONCLUSIONS Transoral versus posterior surgery for atlantoaxial fusion did not differ in 30-day unexpected outcomes. Therefore, spinal pathology, rather than concern for postoperative complications, should adjudicate the technical approach to the atlantoaxial segment.

Dynamic foraminal dimensions during neck extension and rotation in fusion and artificial disc replacement: an observational study.

BACKGROUND: Changes in the dimensions of the cervical neural foramina (CNF) are considered to be a key factor in nerve root compression and development of cervical radiculopathy. However, to what extent foraminal geometry differs between patients who underwent anterior cervical discectomy and fusion (ACDF) and those who underwent total disc arthroplasty with an artificial disc (AD) during physiological motion is largely unknown. PURPOSE: The objective of this study is to compare CNF dimensions during physiological neck motion between ACDF and AD. STUDY DESIGN/SETTING: This is a retrospective comparative analysis of prospectively collected, consecutive, non-randomized series of patients at a single institution. PATIENT SAMPLE: A total of 16 single-level C5-C6 ACDF (4 males, 12 females; 28-71 years) and 7 single-level C5-C6 cervical arthroplasty patients (3 males, 4 females; 38-57 years), at least 12 months after surgery (23.6±6.8 months) were included. OUTCOME MEASURES: Patient demographics, preoperative magnetic resonance imaging (MRI)-based measurements of cervical spine degeneration, and 2-year postoperative measurements of dynamic foraminal geometry were the outcome measures. METHODS: Biplane X-ray images were acquired during axial neck rotation and neck extension. A computed tomography scan was also acquired from C3 to the first thoracic vertebrae. The subaxial cervical vertebrae (C3-C7) were reconstructed into three-dimensional (3D) bone models for use with model-based tracking. Foraminal height (FH) was calculated as the 3D distance between the superior point of the inferior pedicle and the inferior point of the superior pedicle using custom software. Foraminal width (FW) was similarly calculated as the 3D distance between the anterolateral aspect of the superior vertebral body inferior notch and the posterolateral aspect of the inferior vertebral body superior notch. Dynamic foraminal dimensions were quantified as the minimum (FH.Min, FW.Min), the range (FH.Range, FW.Range), and the median (FH.Med, FW.Med) of each trial and then averaged over trials. Mixed model analysis of variance framework was used to examine the differences between ACDF and AD groups. The initial severity of disc degeneration as determined from preoperative MRI images was introduced as covariates in the models. RESULTS: At the operated level (C5-C6), FH.Med and FH.Range were smaller in ACDF than in AD during axial rotation and neck extension (p<.003 to p<.05). At the superior adjacent level (C4-C5), no significant difference was found. At the inferior adjacent level (C6-C7), FW.Range was greater in ACDF than in AD during axial rotation and extension (p<.05). At the non-adjacent level (C3-C4), FW.Range was greater in ACDF than in AD during extension (p<.008). CONCLUSIONS: This study demonstrated decreases in foraminal dimensions and their range for ACDF compared with AD at the operated level. In contrast, it demonstrated increases in the range of foraminal dimensions during motion for ACDF compared with AD at the non-operated segments. Together, these data support the notion that increased mobility at the non-operated segments after ACDF may contribute to a greater risk for adjacent segment degeneration. Because of the significant presence of range variables in the findings, the current data also indicate that a dynamic evaluation is likely more appropriate for evaluation of the differences in foramina between ACDF and AD than a static evaluation.

Traumatic pneumocephaly: trapped air from where?

Traumatic pneumocephaly is literally defined as 'air in the head' after trauma. While this phenomenon has been well described in the literature, our case report is unique in describing diffuse pneumocephalus in the subaponeurotic space, subdural space, subarachnoid space, brain and ventricles without a break in the cranial vault: a 26-year-old man fell from a =9 meter scaffolding in a water tower. Following an arduous and delayed extrication, the patient was unresponsive with loss of pulse requiring intubation, cardiopulmonary resuscitation and release of tension pneumothorax with bilateral thoracostomy tubes. Examination remained poor with a Glasgow Coma Scale of 3. Immediate exploratory laparotomy was performed for a small right retroperitoneal haematoma on Focused Assessment with Sonography for Trauma. Postoperative imaging revealed diffuse pneumocephaly without facial fractures. This case presentation explores unusual causes of fistulous connections with the atmosphere that may lead to air trapped in and around the cranial vault.

Chronic thoracolumbar subdural empyema: Case report and surgical management.

BACKGROUND: Spinal cord abscesses and spinal subdural empyemas are rare and difficult to treat. CASE DESCRIPTION: A 35-year-old male presented to an outside institution with 2 months of progressive low back pain, weakness, and bowel incontinence; he was diagnosed with an L4 epidural abscess that was poorly managed. When the patient presented to our institution, magnetic resonance imaging (MRI) revealed a well-organized chronic subdural abscess at the thoracolumbar junction. Following resection, his back pain resolved but he was left with a residual paraparesis. CONCLUSION: Subdural abscesses are rare and should be considered among the differential diagnoses for intraspinal mass lesions. Treatment should include prompt surgical exploration and decompression combined with appropriate prolonged antibiotic treatment.

Preventive effect of tamsulosin on postoperative urinary retention in neurosurgical patients.

BACKGROUND: Postoperative urinary retention (POUR) is common in neurosurgical patients. The use of alpha-blockade therapy, such as tamsulosin, has benefited many patients with a history of obstructive uropathy by decreasing lower urinary tract symptoms such as distension, infections, and stricture formation, as well as the incidence of POUR. For this study, we targeted patients who had undergone spinal surgery to examine the prophylactic effects of tamsulosin. Increased understanding of this therapy will assist in minimizing the morbidity of spinal surgery. METHODS: We enrolled 95 male patients undergoing spine surgery in a double-blind, randomized, placebo-controlled trial. Patients were randomly assigned to receive either preoperative tamsulosin (N = 49) or a placebo (N = 46) and then followed-up prospectively for the development of POUR after removal of an indwelling urinary catheter (IUC). They were also followed-up for the incidence of IUC reinsertions. RESULTS: The rate of developing POUR was similar in both the groups. Of the 49 patients given tamsulosin, 16 (36%) developed POUR compared to 13 (28%) from the control group (P = 0.455). In the control group, 5 (11%) patients had IUC re-inserted postoperatively, whereas 7 (14%) patients in the tamsulosin group had IUC re-inserted postoperatively (P = 0.616). In patients suffering from axial-type symptoms (i.e., mechanical back pain), 63% who received tamsulosin and 18% from the control group (P = 0.048) developed POUR. CONCLUSION: Overall, there was no statistically significant difference in the rates of developing POUR among patients in either group. POUR is caused by a variety of factors, and further studies are needed to shed light on its etiology.

Dynamic measurements of cervical neural foramina during neck movements in asymptomatic young volunteers.

PURPOSE: Neural foraminal dimensions are considered important in nerve root compression and development of cervical radiculopathy, but baseline data regarding their range during normal motion are not available. An in vivo study of cervical foraminal motion was conducted to characterize normal 3D dynamic foraminal dimensions during physiological neck motion and compare between different tasks and intervertebral segments. METHODS: Biplane X-ray imaging and computed tomography-based markerless tracking were used to measure foraminal height (FH) and width (FW) from five asymptomatic subjects during neck axial rotation and extension. FH and FW were quantified as the minimum (SI.Min and AP.Min), range (SI.Range and AP.Range), and median (SI.Med and AP.Med) of superoinferior (SI) and anteroposterior (AP) dimensions for each trial and as the coefficient of variation of these variables from three trials (SI.Med.CV and AP.Med.CV, SI.Range.CV and AP.Range.CV) at C3-4 through C6-7 levels for each subject. Differences were analyzed using mixed model ANOVA. RESULTS: AP.Range and AP.Med.CV were greater (P < 0.0001) while AP.Min and AP.Range.CV were smaller (P < 0.0006 and P < 0.0005) during neck extension than rotation. SI.Range and SI.Med.CV were greater for extension than rotation at C5-6 (P < 0.002 and P < 0.03), whereas SI.Med.CV was greater for rotation than extension at C3-4 (P < 0.03). AP.Range (P < 0.02), AP.Med.CV (P < 0.05), SI.Range (P < 0.0004), and SI.Med.CV (P < 0.02) were different between cervical levels, the latter two being during extension only. CONCLUSIONS: Patterns of FH and FW during normal motion are different between tasks and cervical levels. These findings are expected to provide a basis for future studies of spinal degeneration and surgical efficacy.

Multifocal Intradural Extramedullary Pilocytic Astrocytomas of the Spinal Cord: A Case Report and Review of the Literature.

Background and importance: Pilocytic astrocytoma (PA) is among the most common of the central nervous system gliomas in the pediatric population; however, it is uncommon in adults. PAs of the spinal cord in adults are even rarer, with only a few cases found in the literature. We report here the first case in the literature of multifocal intradural extramedullary spinal cord PAs in an adult. Clinical presentation: Our patient is a 56-yr-old female who presented with loss of balance and an ataxic gait. Multiple extramedullary spinal cord tumors were identified intraoperatively, the lesions completely resected, and all diagnosed as PAs. Conclusion: This case illustrates a unique instance of multifocal intradural extramedullary spinal cord PAs in an adult with no previous history of PA during childhood, no known familial syndromes, and no brain involvement.

Racial disparities in the diagnosis and management of trigeminal neuralgia.

OBJECTIVE A number of studies have documented inequalities in care and outcomes for a variety of clinical conditions. The authors sought to identify racial and socioeconomic disparities in the diagnosis and treatment of trigeminal neuralgia (TN), as well as the potential underlying reasons for those disparities, which could serve as areas of focus for future quality improvement initiatives. METHODS The medical records of patients with an ICD-9 code of 350.1, signifying a diagnosis of TN, at the Henry Ford Medical Group (HFMG) in the period from 2006 to 2012 were searched, and clinical and socioeconomic data were retrospectively reviewed. Analyses were conducted to assess potential racial differences in subspecialty referral patterns and the specific type of treatment modality undertaken for patients with TN. RESULTS The authors identified 652 patients eligible for analysis. Compared with white patients, black patients were less likely to undergo percutaneous ablative procedures, stereotactic radiosurgery, or microvascular decompression (p < 0.001). However, there was no difference in the likelihood of blacks and whites undergoing a procedure once they had seen a neurosurgeon (67% vs 70%, respectively; p = 0.712). Blacks and whites were equally likely to be seen by a neurologist or neurosurgeon if they were initially seen in either the emergency room (38% vs 37%, p = 0.879) or internal medicine (48% vs 50%, p = 0.806). Among patients diagnosed (268 patients) after the 2008 publication of the European Federation of Neurological Societies and the American Academy of Neurology guidelines for medical therapy for TN, fewer than 50% were on medications sanctioned by the guidelines, and there were no statistically significant racial disparities between white and black patients (p = 0.060). CONCLUSIONS According to data from a large database from one of the nation's largest comprehensive health care systems, there were significant racial disparities in the likelihood of a patient undergoing a procedure for TN. This appeared to stem from outside HFMG from a difference in referral patterns to the neurologists and neurosurgeons.

Application of morphometric analysis to patients with lung cancer metastasis to the spine: a clinical study.

OBJECTIVE Predicting the survival rate for patients with cancer is currently performed using the TNM Classification of Malignant Tumors (TNM). Identifying accurate prognostic markers of survival would allow better treatment stratification between more aggressive treatment strategies or palliation. This is especially relevant for patients with spinal metastases, who all have identical TNM staging and whose surgical decision-making is potentially complex. Analytical morphometrics quantifies patient frailty by measuring lean muscle mass and can predict risk for postoperative morbidity after lumbar spine surgery. This study evaluates whether morphometrics can be predictive of survival in patients with spinal metastases. METHODS Utilizing a retrospective registry of patients with spinal metastases who had undergone stereotactic body radiation therapy, the authors identified patients with primary lung cancer. Morphometric measurements were taken of the psoas muscle using CT of the lumbar spine. Additional morphometrics were taken of the L-4 vertebral body. Patients were stratified into tertiles based on psoas muscle area. The primary outcome measure was overall survival, which was measured from the date of the patient's CT scan to date of death. RESULTS A total of 168 patients were identified, with 54% male and 54% having multiple-level metastases. The median survival for all patients was 185.5 days (95% confidence interval [CI] 146-228 days). Survival was not associated with age, sex, or the number of levels of metastasis. Patients in the smallest tertile for the left psoas area had significantly shorter survival compared with a combination of the other two tertiles: 139 days versus 222 days, respectively, hazard ratio (HR) 1.47, 95% CI 1.06-2.04, p = 0.007. Total psoas tertiles were not predictive of mortality, but patients whose total psoas size was below the median size had significantly shorter survival compared with those greater than the median size: 146 days versus 253.5 days, respectively, HR 1.43, 95% CI 1.05-1.94, p = 0.025. To try to differentiate small body habitus from frailty, the ratio of psoas muscle area to vertebral body area was calculated. Total psoas size became predictive of mortality when normalized to vertebral body ratio, with patients in the lowest tertile having significantly shorter survival (p = 0.017). Left psoas to vertebral body ratio was also predictive of mortality in patients within the lowest tertile (p = 0.021). Right psoas size was not predictive of mortality in any calculations. CONCLUSIONS In patients with lung cancer metastases to the spine, morphometric analysis of psoas muscle and vertebral body size can be used to identify patients who are at risk for shorter survival. This information should be used to select patients who are appropriate candidates for surgery and for the tailoring of oncological treatment regimens.

A cohort study of the morbidity of combined anterior-posterior cervical spinal fusions: incidence and predictors of postoperative dysphagia.

PURPOSE: To identify risk factors that may lead to the development of dysphagia after combined anterior and posterior (360°) cervical fusion surgery. METHODS: A single center, retrospective analysis of patients who had same-day, 360° fusion at Henry Ford Hospital between 2008 and 2012 was performed. Variables analyzed included demographics, medical co-morbidities, levels fused, and degree of dysphagia. RESULTS: The overall dysphagia rate was 37.7 %. Patients with dysphagia had a longer mean length of stay (p < 0.001), longer mean operative time (p < 0.001), greater intraoperative blood loss (p = 0.002), and fusion above the fourth cervical vertebra, C4, (p = 0.007). There were no differences in the rates of dysphagia when comparing patients undergoing primary or revision surgery (p = 0.554). CONCLUSION: Prolonged surgery and fusion above C4 lead to higher rates of dysphagia after 360° fusions. Prior anterior cervical fusion does not increase the risk of dysphagia development.

Surgical Management of Dural Arteriovenous Fistula After Craniotomy: Case Report and Review of Literature.

BACKGROUND: Development of dural arteriovenous fistula (dAVF) with cortical venous drainage at the site of previous craniotomy is a rare manifestation of nontraumatic subarachnoid hemorrhage (SAH). The authors present a case of postcraniotomy dAVF formation and discuss plausible underlying mechanisms of fistula formation and treatment options as well as review the literature. CASE DESCRIPTION: A 62-year-old man, who had undergone craniotomy 2 decades previously, presented with SAH. Workup revealed a low-flow dAVF with leptomeningeal venous drainage at the posterior margin of the craniotomy. Surgical resection of fistula was undertaken that resulted in cure. CONCLUSIONS: Spontaneous SAH in patients with a previous history of an intracranial procedure (e.g., craniotomy, ventriculostomy) should prompt detailed imaging evaluation. In the absence of vascular disease, meticulous review of the angiogram must be undertaken to rule out dAVF at the procedure site and it should be treated definitively.

Surgical Management of Giant Intracranial Arteriovenous Malformations: A Single Center Experience over 32 years.

OBJECTIVE: Treatment of giant intracranial arteriovenous malformations (gAVMs) is a formidable challenge for neurosurgeons and carries significant morbidity and mortality rates for patients compared with smaller AVMs. In this study, we reviewed the treatments, angiographic results, and clinical outcomes in 64 patients with gAVMs who were treated at Henry Ford Hospital between 1980 and 2012. METHODS: The arteriovenous malformation (AVM) database at our institution was queried for patients with gAVMs (≥ 6 cm) and data regarding patient demographics, presentation, AVM angioarchitecture, and treatments were collected. Functional outcomes as well as complications were analyzed. RESULTS: Of the 64 patients, 33 (51.6%) were female and 31 (48.4%) were male, with an average age of 45.7 years (SD ± 15.5). The most common symptoms on presentation were headaches (50%), seizures (50%), and hemorrhage (41%). The mean AVM size was 6.65 cm (range, 6-9 cm). Only 6 AVMs (9.4%) were located in the posterior fossa. The most common Spetzler-Martin grade was V, seen in 64% of patients. Of the 64 patients, 42 (66%) underwent surgical excision, 10 (15.5%) declined any treatment, 8 (12.5%) were deemed inoperable and followed conservatively, 2 (3%) had stand-alone embolization, 1 (1.5%) had embolization before stereotactic radiosurgery, and 1 (1.5%) received stereotactic radiosurgery only. Complete obliteration was achieved in 90% of the surgical patients. Mortality rate was 19% in the surgical cohort compared with 22% in the observation cohort (P = 0.770). CONCLUSIONS: Treatment of gAVMs carries significant morbidity and mortality; however, good outcomes are attainable with a multimodal treatment approach in carefully selected patients.