Timing of surgery and radiotherapy in the management of metastatic spine disease: expert opinion.

BACKGROUND: Combined surgery and radiotherapy, in the treatment of metastatic disease of the spine, is now emerging as the gold standard of care where there is an indication for spinal stabilization and/or surgical decompression. However potential complications related to wound healing can occur with radiation delivered shortly before or after to surgery. The purpose of this study was to understand the practice of leading radiation oncologists and spine surgeons with regards to the timing of radiation (conventional and stereotactic) and surgery for the management of spinal metastases. METHODS: Questionnaires were sent to leading radiation oncologists and spine surgeons throughout North America and completed via mail, email or internet. RESULTS: Eighty-six responses were received from radiation oncologists and 27 from spine surgeons. A total of 58% recommended waiting either 1 or 2 weeks after radiotherapy before operating on patients with spinal metastases. With radiotherapy administered after surgery, 62% of respondents suggested either a 1 or 2 weeks interval was sufficient. CONCLUSIONS: There appeared to be no significant difference in practice with the use of stereotactic radiotherapy though surgeons tend to accept a shorter interval in this subset of patients. We recommend that the interval between radiotherapy and surgery (and vice versa) should ideally be a minimum of 2 weeks.

Previously Identified Common Post-Injury Adverse Events in Traumatic Spinal Cord Injury-Validation of Existing Literature and Relation to Selected Potentially Modifiable Comorbidities: A Prospective Canadian Cohort Study.

Adverse events (AEs) are common during care in patients with traumatic spinal cord injury (tSCI). Increased risk of AEs is linked to patient factors including pre-existing comorbidities. Our aim was to examine the relationships between patient factors and common post-injury AEs, and identify potentially modifiable comorbidities. Adults with tSCI admitted to a Level I acute specialized spine center between 2006 and 2014 who were enrolled in the Rick Hansen SCI Registry (RHSCIR) and had AE data collected using the Spine Adverse Events Severity system were included. Patient demographic, neurological injury, and comorbidities data were obtained from RHSCIR. Potentially modifiable comorbidities were grouped into health-related conditions, substance use/withdrawal, and psychiatric conditions. Negative binomial regression and multiple logistic regression were used to model the impact of patient factors on the number of AEs experienced and the occurrence of the five previously identified common AEs, respectively. Of the 444 patients included in the study, 24.8% reported a health-related condition, 15.3% had a substance use/withdrawal condition, 8% reported having a psychiatric condition; and 79.3% experienced one or more AEs. Older age (p = 0.004) and more severe injuries (p < 0.001) were nonmodifiable independent variables significantly associated with increased AEs. The AEs experienced by patients were urinary tract infections (42.8%), pneumonia (39.2%), neuropathic pain (31.5%), delirium (18.2%), and pressure ulcers (11.0%). Risk of delirium increased in those with substance use/withdrawal; and pneumonia risk increased with psychiatric comorbidities. Opportunity exists to develop clinical algorithms that include these types of risk factors to reduce the incidence and impact of AEs.

Rural and Urban Living in Persons with Spinal Cord Injury and Comparing Environmental Barriers, Their Health, and Quality-of-Life Outcomes.

There is worldwide geographic variation in the epidemiology of traumatic spinal cord injury (tSCI). The aim of this study was to determine whether environmental barriers, health status, and quality-of-life outcomes differ between patients with tSCI living in rural or urban settings, and whether patients move from rural to urban settings after tSCI. A cohort review of the Rick Hansen SCI Registry (RHSCIR) was undertaken from 2004 to 2012 for one province in Canada. Rural/urban setting was determined using postal codes. Outcomes data at 1 year in the community included the Short Form-36 Version 2 (SF36v2™), Life Satisfaction Questionnaire, Craig Hospital Inventory of Environmental Factors-Short Form (CHIEF-SF), Functional Independent Measure® Instrument, and SCI Health Questionnaire. Statistical methodologies used were t test, Mann-Whitney U test, and Fisher's exact or χ2 test. In the analysis, 338 RHSCIR participants were included; 65 lived in a rural setting and 273 in an urban setting. Of the original patients residing in a rural area at discharge,10 moved to an urban area by 1 year. Those who moved from a rural to urban area reported a lower SF-36v2™ Mental Component Score (MCS; p = 0.04) and a higher incidence of depression at 1 year (p = 0.04). Urban patients also reported a higher incidence of depression (p = 0.02) and a lower CHIEF-SF total score (p = 0.01) indicating fewer environmental barriers. No significant differences were found in other outcomes. Results suggest that although the patient outcomes are similar, some patients move from rural to urban settings after tSCI. Future efforts should target screening mental health problems early, especially in urban settings.

Economic evaluation comparing intraoperative cone beam CT-based navigation and conventional fluoroscopy for the placement of spinal pedicle screws: a patient-level data cost-effectiveness analysis.

BACKGROUND CONTEXT: Pedicle screws are routinely used in contemporary spinal surgery. Screw misplacement may be asymptomatic but is also correlated with potential adverse events. Computer-assisted surgery (CAS) has been associated with improved screw placement accuracy rates. However, this technology has substantial acquisition and maintenance costs. Despite its increasing usage, no rigorous full economic evaluation comparing this technology to current standard of care has been reported. PURPOSE: Medical costs are exploding in an unsustainable way. Health economic theory requires that medical equipment costs be compared with expected benefits. To answer this question for computer-assisted spinal surgery, we present an economic evaluation looking specifically at symptomatic misplaced screws leading to reoperation secondary to neurologic deficits or biomechanical concerns. STUDY DESIGN/SETTING: The study design was an observational case-control study from prospectively collected data of consecutive patients treated with the aid of CAS (treatment group) compared with a matched historical cohort of patients treated with conventional fluoroscopy (control group). PATIENT SAMPLE: The patient sample consisted of consecutive patients treated surgically at a quaternary academic center. OUTCOME MEASURES: The primary effectiveness measure studied was the number of reoperations for misplaced screws within 1 year of the index surgery. Secondary outcome measures included were total adverse event rate and postoperative computed tomography usage for pedicle screw examination. METHODS: A patient-level data cost-effectiveness analysis from the hospital perspective was conducted to determine the value of a navigation system coupled with intraoperative 3-D imaging (O-arm Imaging and the StealthStation S7 Navigation Systems, Medtronic, Louisville, CO, USA) in adult spinal surgery. The capital costs for both alternatives were reported as equivalent annual costs based on the annuitization of capital expenditures method using a 3% discount rate and a 7-year amortization period. Annual maintenance costs were also added. Finally, reoperation costs using a micro-costing approach were calculated for both groups. An incremental cost-effectiveness ratio was calculated and reported as cost per reoperation avoided. Based on reoperation costs in Canada and in the United States, a minimal caseload was calculated for the more expensive alternative to be cost saving. Sensitivity analyses were also conducted. RESULTS: A total of 5,132 pedicle screws were inserted in 502 patients during the study period: 2,682 screws in 253 patients in the treatment group and 2,450 screws in 249 patients in the control group. Overall accuracy rates were 95.2% for the treatment group and 86.9% for the control group. Within 1 year post treatment, two patients (0.8%) required a revision surgery in the treatment group compared with 15 patients (6%) in the control group. An incremental cost-effectiveness ratio of $15,961 per reoperation avoided was calculated for the CAS group. Based on a reoperation cost of $12,618, this new technology becomes cost saving for centers performing more than 254 instrumented spinal procedures per year. CONCLUSIONS: Computer-assisted spinal surgery has the potential to reduce reoperation rates and thus to have serious cost-effectiveness and policy implications. High acquisition and maintenance costs of this technology can be offset by equally high reoperation costs. Our cost-effectiveness analysis showed that for high-volume centers with a similar case complexity to the studied population, this technology is economically justified.

Patient and surgeon radiation exposure during spinal instrumentation using intraoperative computed tomography-based navigation.

BACKGROUND CONTEXT: Imaging modalities used to visualize spinal anatomy intraoperatively include X-ray studies, fluoroscopy, and computed tomography (CT). All of these emit ionizing radiation. PURPOSE: Radiation emitted to the patient and the surgical team when performing surgeries using intraoperative CT-based spine navigation was compared. STUDY DESIGN/SETTING: This is a retrospective cohort case-control study. PATIENT SAMPLE: Seventy-three patients underwent CT-navigated spinal instrumentation and 73 matched controls underwent spinal instrumentation with conventional fluoroscopy. OUTCOME MEASURES: Effective doses of radiation to the patient when the surgical team was inside and outside of the room were analyzed. The number of postoperative imaging investigations between navigated and non-navigated cases was compared. METHODS: Intraoperative X-ray imaging, fluoroscopy, and CT dosages were recorded and standardized to effective doses. The number of postoperative imaging investigations was compared with the matched cohort of surgical cases. A literature review identified historical radiation exposure values for fluoroscopic-guided spinal instrumentation. RESULTS: The 73 navigated operations involved an average of 5.44 levels of instrumentation. Thoracic and lumbar instrumentations had higher radiation emission from all modalities (CT, X-ray imaging, and fluoroscopy) compared with cervical cases (6.93 millisievert [mSv] vs. 2.34 mSv). Major deformity and degenerative cases involved more radiation emission than trauma or oncology cases (7.05 mSv vs. 4.20 mSv). On average, the total radiation dose to the patient was 8.7 times more than the radiation emitted when the surgical team was inside the operating room. Total radiation exposure to the patient was 2.77 times the values reported in the literature for thoracolumbar instrumentations performed without navigation. In comparison, the radiation emitted to the patient when the surgical team was inside the operating room was 2.50 lower than non-navigated thoracolumbar instrumentations. The average total radiation exposure to the patient was 5.69 mSv, a value less than a single routine lumbar CT scan (7.5 mSv). The average radiation exposure to the patient in the present study was approximately one quarter the recommended annual occupational radiation exposure. Navigation did not reduce the number of postoperative X-rays or CT scans obtained. CONCLUSIONS: Intraoperative CT navigation increases the radiation exposure to the patient and reduces the radiation exposure to the surgeon when compared with values reported in the literature. Intraoperative CT navigation improves the accuracy of spine instrumentation with acceptable patient radiation exposure and reduced surgical team exposure. Surgeons should be aware of the implications of radiation exposure to both the patient and the surgical team when using intraoperative CT navigation.

Adverse events in surgically treated cervical spondylopathic myelopathy: a prospective validated observational study.

STUDY DESIGN: Prospective observational study. OBJECTIVE: Using validated tools to accurately identify and quantify incidence of and risks for inpatient adverse events (AEs) associated with surgical management of cervical spondylopathic myelopathy (CSM) with the goal of assisting physicians and patients in decision making. To identify patient-/disease-/technique-specific, independent risk factors for developing AEs perioperatively and affecting length of stay for patients treated surgically for CSM. SUMMARY OF BACKGROUND DATA: Previous studies have reported an overall perioperative complication rate between 15.6% and 18.52%. METHODS: A total of 104 patients underwent surgery for CSM in our academic quaternary referral center. The average age was 60.3 years (range, 34-86 yr) with a male preponderance (n = 77, 74%). The severity of myelopathy and significant comorbidities was measured and was in keeping with previously assessed populations. Surgical approach was anterior-alone (39.4%), posterior-alone (55.8%), or combined (4.8%) surgery. Inpatient AE data were collected in a rigorous, contemporaneous fashion using the previously validated Spine Adverse Events Severity System (SAVES) tool. RESULTS: A total AE rate of 42.3% was documented in surgically managed patients with CSM (intraoperative = 13.5%, postoperative = 37.5%). Statistically significant risk factors for postoperative AEs were identified, including number of comorbidities (P = 0.012), anterior surgical approach (P = 0.003), and number of levels operated on (P = 0.031). Multiple risk factors for length of stay were also identified, including number of AEs (P < 0.0001), Nurick Score (P < 0.0001), number of levels operated on (P = 0.006), and occurrence of deep wound infection (P < 0.0001). CONCLUSION: We report higher perioperative AE rates than previously recognized, due to the use of a validated, rigorous data collection tool. Multiple novel patient/disease severity/surgical factors with high statistical significance on perioperative AEs have been identified. LEVEL OF EVIDENCE: 3.

Incidence, impact, and risk factors of adverse events in thoracic and lumbar spine fractures: an ambispective cohort analysis of 390 patients.

BACKGROUND CONTEXT: Adverse events (AEs) in thoracic and lumbar spine fractures are common, but little is known about the type of AEs that are specific to this population. Furthermore, very little is known about the incidence and clinical impact of these AEs on patients in the presence of traumatic spinal cord injury and whether they are treated operatively or nonoperatively. PURPOSE: The purpose of this study was to determine primarily the incidence of AEs in patients with thoracic or lumbar spine fractures treated both operatively and nonoperatively and their impact on length of stay (LOS) and secondarily the difference in the incidence of AEs in both neurologically intact and compromised patients. STUDY DESIGN/SETTING: This is an ambispective cohort study at a quaternary referral center. PATIENT SAMPLE: Patients admitted at our institution with thoracic or lumbar fractures from January 2009 to December 2013 were identified. Patients with full Spine Adverse Events Severity System (SAVES) data were included. OUTCOME MEASURES: Number and type of AEs collected from SAVES were assessed. Impact of AE on acute LOS was also determined. METHODS: Data on intraoperative, preoperative, and postoperative AEs were prospectively collected using the SAVES data collection. Logistic regression was used to model the likelihood of experiencing at least one AE based on the patient characteristics. The impact of the total number of AEs experienced by a patient and that of each of the most common AEs on LOS was determined using Poisson regression. RESULTS: Three hundred and ninety patients were included in the final analysis. Two hundred and seventy-six patients (70.8%) were treated operatively. One hundred and forty patients (36%) experienced neurologic deficit as a result of their initial injury. Adverse events occurred 56% of the time in the operatively treated patients and only 13% of the time in the nonoperative group. The presence of neurologic deficit increased the risk of AEs especially in high thoracic (T1-T6) trauma increasing the odds of having an AE by 12.1 (p<.0001). The most common AEs were urinary tract infections (19.7%), neuropathic pain (12.3%), pneumonias (11.8%), delirium (10.5%), and ileus (6.2%). Length of hospital stay increased significantly with pneumonia (p<.0001) and delirium (p=.0001). CONCLUSIONS: The presence of neurologic injury and the need for operative fixation of thoracic or lumbar injuries lead to a greater risk of AEs. Only pneumonia and delirium consistently increase LOS.

Prospective analysis of adverse events in surgical treatment of degenerative spondylolisthesis.

BACKGROUND CONTEXT: Surgical adverse event (AE) monitoring is imprecise, of uncertain validity, and tends toward underreporting. Reports focus on specific procedures rather than outcomes in the context of presenting diagnosis. Specific intraoperative (intraop) or postoperative (postop) AEs that may be independently associated with degenerative spondylolisthesis (DS) have never been reported. PURPOSE: The primary purpose was to assess the AE profile of surgically treated patients with L4-L5 DS. The secondary goal was to identify potential risk factors that correlate with those AEs. STUDY DESIGN/SETTING: Prospective cohort and academic quaternary spine center. PATIENT SAMPLE: Ninety-two patients with L4-L5 DS were treated surgically, discharged from Vancouver General Hospital between January 1, 2009 and December 31, 2010. OUTCOME MEASURES: Incidence rates and odds ratios. METHODS: Prospective AE data were analyzed using univariate analyses, forward selection regression models, and Spearman correlation coefficients. Results were compared with outcomes reported in the Spine Patient Outcomes Research Trial. RESULTS: No AEs were seen in 57.6% of patients, one AE in 17.4%, and two or more AEs in 17.4%. Dural tears (6.5%) and intraop bone-implant interface failure requiring revision (3.3%) were the most common intraop AEs. Postoperatively, the most frequent AEs were urinary tract infection (10.9%), delirium (5.4%), neuropathic pain (4.4%), deep wound infection (3.3%), and superficial wound infection (3.3%). The odds of an intraop AE increased by 9% (95% confidence interval [CI] 1-18) per year of age at admission. Adjusted Charlson comorbidity index (CCI) did not correlate with number of AEs experienced. The odds of postop delirium correlated with CCI (odds ratio [OR] 3.39, 95% CI 1.12-10.24) and dural tear (OR 35.84, 95% CI 1.72-747.45). Length of stay was statistically significant and was influenced by two or more AEs, CCI, postop loss of correction, cerebrospinal fluid leak, deep wound infection, noninfected wound drainage, and gender. CONCLUSIONS: Risk of intraop AEs, but not postop AEs, increased with increasing age. Having multiple comorbidities does not predispose to more AEs. Infections predominate among the postop AEs. Patients at increased risk of delirium or of having an increased length of hospital stay may more easily be predicted. Studies specifically designed to prospectively assess AEs have the potential to more accurately identify postop AE rates.

The validity of administrative data to classify patients with spinal column and cord injuries.

International Classification of Diseases (ICD) codes are used to document patient morbidity in administrative databases. Although administrative data are used for research purposes, the validity of the data to accurately describe clinical diagnostic information is uncertain. We compared the clinical diagnoses for spinal cord and column injuries from a longitudinal patient registry, the Rick Hansen Spinal Cord Injury Registry (RHSCIR), to the ICD-10 spinal injury codes from the Discharge Abstract Database (DAD) at one institution. There were 603 RHSCIR participants with data describing the spinal cord injury, and 341 had data on the spinal column injury. The validity of DAD data to describe spinal injuries was evaluated using the sensitivity and positive predictive values of specific ICD-10 codes; 5.3% of the spinal column injuries and 10.9% of the spinal cord injuries documented in RHSCIR were missed in data from the DAD using ICD-10 codes. The most problematic spinal column ICD-10 code was the dislocation of the cervical vertebra (S13.1); only 14.0% of the dislocations of the cervical vertebrae in RHSCIR were correctly coded in the DAD. The most problematic spinal cord injury ICD-10 code was the incomplete lesion of the lumbar spinal cord (S34.1X); 66.7% of incomplete lesions of the lumbar spinal cord in RHSCIR were correctly coded in the DAD. The validity of DAD data to code spinal injuries is variable, and cannot be reliably used to classify all types of spinal injuries. Patient registries, such as RHSCIR, should be used if accurate detailed diagnostic data are required.

Feasibility of patient recruitment into clinical trials of experimental treatments for acute spinal cord injury.

Clinical trials of experimental neuroprotective and neuroregenerative therapies for acute spinal cord injury (SCI) typically require large numbers of patients to be enrolled. An important factor in designing such trials is the number of patients that can be realistically recruited at a given institution. The total number of patients with acute SCI treated at a neurotrauma centre is typically considered when such a site becomes a recruiting centre for a clinical trial. However, only a fraction of patients may be truly eligible due to the inclusion and exclusion criteria of the trial. This study was conducted to estimate the proportion of patients with acute SCI who would theoretically satisfy basic inclusion criteria for such a hypothetical clinical trial. Using a local prospective database, we reviewed 406 patients with acute traumatic SCI admitted between 2005 and 2009. 259 of 406 patients (64%) presented within 12 hours of injury, 53 patients (13%) between 12 hours and 24 hours, and 30 patients (7%) between 24 hours and 48 hours. Patients were assessed on admission using the American Spinal Injury Association Impairment Scale: category A, 39% of patients; B, 11%; C, 17%; and D, 28%. The number of patients who presented with injuries or other conditions that would likely exclude them from enrolment was 30%. Thus, of a total of 406 patients with SCI admitted over four years, the number who would have been eligible for an acute clinical trial was disappointingly small. This study is the first to quantify this challenging aspect of conducting acute SCI clinical trials, and provides guidance for those planning such initiatives.