Case Report of a Hemangioblastoma Originating from the T1 Spinal Nerve Treated with in Toto Resection, Hemicorporectomy and Pedicle Screw Stabilization.

Introduction: Previously, only 40 cases with extradural hemangioblastoma at the spinal nerve (none at the T1 nerve root) have been described in the medical literature. In toto, resection of this hypervascular tumor is essential to avoid bleeding complications. Surgery for hemangioblastoma at the cervicothoracic junction is complex and nerve resection of the T1 results in specific neurodeficits of the hand muscles which are not well known. Case Report: A 34-year-old woman was diagnosed with a slowly growing tumor located at the left foramen T1/T2. Pressure from the tumor resulted in Horner's syndrome and pain and paresthesia in the upper extremity. The tumor was resected in toto through a posterior midline approach and rib resection and transection of the left T1 and T2 spinal nerves. T2 hemicorporectomy and spinal stabilization were performed to gain access to and mobilize the tumor ventrally. Ptosis decreased after surgery and no neurodeficit was observed except the expected deficit (no deficit was present preoperatively) caused by the T1 resection specifically a small decrease in strength of the abductor and flexor pollicis brevis and opponens pollicis and the lateral two lumbricals. Histological examination of the tumor demonstrated a hemangioblastoma. von Hippel-Lindau disease was ruled out by genetic testing of the patient's blood. Eight-month postoperatively, all pre-operative symptoms had decreased considerably and the radiographic examination shoved unchanged pedicle screw/rod stabilization of the cervicothoracic junction. Conclusion: Hemangioblastoma is a rare hypervascular tumor very rarely located at the spinal nerve. The tumor should be resected in toto to avoid recurrence and bleeding. In the current case, the location was at the T1 root necessitating complex surgery with laminectomies and hemicorporectomy of T2 and a posterior rib resection/thoracotomy. Spinal stabilization is mandatory. Preferably embolization should be performed preoperatively. T1 transection results in a specific neurodeficit which should be explained to the patient preoperatively. The patients should undergo genetic testing for Hippel-Lindau disease.

Team-based digital communication reduced patient-initiated phone calls to the hospital and improved patient satisfaction after orthopedic surgery: a randomized controlled trial in 70 patients.

BACKGROUND AND PURPOSE: Post-discharge inquiries to the hospital are predominantly conducted through phone calls. The rigid timing of these calls is inconvenient for patients and disrupts the workflows of healthcare professionals. The aim of this study was to investigate the effect of a team-based digital communication intervention (eDialogue) facilitated through a messenger-like commercial solution on patient-initiated phone calls to the hospital after discharge. Secondarily, we investigated other patient-initiated contacts, patients' perception of continuity of care, and their perception of feeling safe and satisfied after hospital discharge. METHODS: On the day of discharge, 70 surgically treated orthopedic patients were randomized to the intervention group with access to eDialogue (n = 35) or the control group with standard communication pathways by phone call (n = 35) for the following 8 weeks. Through eDialogue, the intervention group had access to team-based asynchronous digital communication in text and photos with healthcare professionals across disciplines and sectors. Inclusion criteria were discharge to own home and receipt of rehabilitation services from both hospital and primary care after discharge. RESULTS: We found a significant reduction in the mean number of patient-initiated phone calls to the hospital from 2.3 (95% confidence interval [CI] 1.4-4.1) in the control group to 0.5 (CI 0.3-1.0) in the intervention group (P = 0.004). Across groups, patients reported similar perceptions of continuity of care; however, the participants in the intervention group expressed significantly improved perceptions of, and satisfaction with, access to healthcare after discharge. CONCLUSION: Access to eDialogue reduced patient-initiated phone calls to the hospital, enhanced patient satisfaction with healthcare accessibility, and did not compromise patients' perception of continuity of care after discharge compared with standard communication pathways.

A propensity-matched study of patients with symptomatic lumbar spinal stenosis opting for surgery versus not.

Introduction: Although most surgeons treating patients with lumbar spinal stenosis (LSS) believe that surgical treatment is superior to conservative measures, systematics reviews have concluded that no solid evidence support this. Research question: To compare change at 1-year of walking ability, health-related quality of life, leg and back pain in patients with symptomatic LSS referred to a spine surgery clinic who opted for surgery and those who did not. Material and methods: The study included 149 operated and 149 non-operated patients seen by spine surgeons and diagnosed with LSS. The non-operated patients were propensity-matched to a cohort retrieved from the Danish national spine registry. Matching was done on demographics and baseline outcome measures. The outcomes was walking improvement measured by item 4 of the Oswestry Disability Index, EQ-5D-3L, global assessment (GA) of back/leg pain, back and leg pain on the Visual Analogue Scale and the Short Form 36 transition item 2. Results: Less than half of the non-operated reached MCID on EQ-5D-3L, VAS pain legs or VAS pain back where 2/3 of the operated did. The largest difference was VAS back pain where 27.5% of the non-operated reached an MCID of 12 points compared to 71.8% in the operated group. Discussion and conclusion: Surgical treated patients improved better than non-operated on all outcome measures. However, further research is required to compare the effectiveness of surgical decompression with non-operative care for LSS patients.

PROPOSE. Development and validation of a prediction model for shared decision making for patients with lumbar spinal stenosis.

Background: Decompression for lumbar spinal stenosis (LSS) is the most frequently performed spine surgery in Denmark. According to the Danish spine registry DaneSpine, at 1 year after surgery, about 75% of patients experiences considerable pain relief and around 66% improvement in quality of life. However, 25% do not improve very much. We have developed a predictive decision support tool, PROPOSE. It is intended to be used in the clinical conversation between healthcare providers and LSS patients as a shared decision-making aid presenting pros and cons of surgical intervention. This study presents the development and evaluation of PROPOSE in a clinical setting. Methods: For model development, 6.357 LSS patients enrolled in DaneSpine were identified. For model validation, predictor response and predicted outcome was collected via PROPOSE from 228 patients. Observed outcome at 1 year was retrieved from DaneSpine. All participants were treated at 3 Danish spine centers. The outcome measures presented are improvement in walking distance, the Oswestry Disability Index, EQ-5D-3L and leg/back pain on the Visual Analog Scale. Outcome variables were dichotomized into success (1) and failure (0). With the exception of walking distance, a success was defined as reaching minimal clinically important difference at 1-year follow-up. Models were trained using Multivariate Adaptive Regression Splines. Performance was assessed by inspecting confusion matrix, ROC curves and comparing GCV (generalized cross-validation) errors. Final performance of the models was evaluated on independent test data. Results: The walking distance model demonstrated excellent performance with an AUC of 0.88 and a Brier score of 0.14. The VAS leg pain model had the lowest discriminatory performance with an AUC of 0.67 and a Brier score of 0.22. Conclusions: PROPOSE works in a real-world clinical setting as a proof of concept and demonstrates acceptable performance. It may have the potential of aiding shared decision making.

Usability and performance expectancy govern spine surgeons' use of a clinical decision support system for shared decision-making on the choice of treatment of common lumbar degenerative disorders.

Study design: Quantitative survey study is the study design. Objectives: The study aims to develop a model for the factors that drive or impede the use of an artificial intelligence clinical decision support system (CDSS) called PROPOSE, which supports shared decision-making on the choice of treatment of ordinary spinal disorders. Methods: A total of 62 spine surgeons were asked to complete a questionnaire regarding their behavioral intention to use the CDSS after being introduced to PROPOSE. The model behind the questionnaire was the Unified Theory of Acceptance and Use of Technology. Data were analyzed using partial least squares structural equation modeling. Results: The degree of ease of use associated with the new technology (effort expectancy/usability) and the degree to which an individual believes that using a new technology will help them attain gains in job performance (performance expectancy) were the most important factors. Social influence and trust in the CDSS were other factors in the path model. r2 for the model was 0.63, indicating that almost two-thirds of the variance in the model was explained. The only significant effect in the multigroup analyses of path differences between two subgroups was for PROPOSE use and social influence (p = 0.01). Conclusion: Shared decision-making is essential to meet patient expectations in spine surgery. A trustworthy CDSS with ease of use and satisfactory predictive ability promoted by the leadership will stand the best chance of acceptance and bridging the communication gap between the surgeon and the patient.

The magnetic field strength and the force distance dependency of the magnetically controlled growing rods used for early onset scoliosis.

Magnetically controlled growing rods (MCGR's) have revolutionized the treatment of early-onset scoliosis (EOS) because painless lengthenings can be done in the outpatient clinic without anesthesia. Untreated EOS leads to respiratory insufficiency and reduced life expectancy. However, MCGR's have inherent complications like non-functioning of the lengthening mechanism. We quantify an important failure mechanism and give advice on how to avoid this complication. The magnetic field strength was measured on new/explanted rods at different distances between the external remote controller and the MCGR and likewise in patients before/after distractions. The magnetic field strength of the internal actuator decayed fast with increasing distances and plateaued at 25-30 mm approximating zero. Two new and 12 explanted MCGRs was used for the lab measurements of the elicited force using a forcemeter. At a distance of 25 mm, the force was reduced to approximately 40% (ca. 100 N) compared to zero distance (ca. 250 N), most so for explanted rods. This is used to point out the importance of minimizing the implantation depth to ensure proper functionality of the rod lengthening in clinical use for EOS patients. A distance of 25 mm from skin to MCGR should be considered a relative contraindication to clinical use in EOS patients.

Validating the predictive precision of the dialogue support tool on Danish patient cohorts.

Background: Despite advances in surgical techniques and diagnostics, some patients remain unsatisfied with the result following spine surgery. One way to improve patient satisfaction may be found in better alignment of expectations. Prognostic tools might prove useful in strengthening surgeon-patient communication prior to surgery. The purpose of this study is to assess the predictive capabilities of the Swedish based Dialogue Support (DS) tool for spine surgery on a Danish population. Methods: The study included the diagnoses lumbar disc herniation, lumbar spinal stenosis, and lumbar degenerative disc disease. A total of 5.954 patients were retrieved from the Danish national spine registry (DaneSpine). For each group, 200 random cases with complete preoperative and 1 year follow-up data were selected. Two outcome measures were used: Global assessment of pain (GA pain) and satisfaction with outcome. Predictions were produced by manual entry in the DS application. Goodness of fit tests were used to compare the predicted distribution of proportions with successful outcomes (GA pain) to the actual distribution in the three samples. Binomial tests were performed to evaluate the predicted proportion of satisfied patients. Furthermore, ROC-curves, calibration plots, and metrics were calculated to assess the predictive performance. Results: ROC curves showed comparable AUC values with the values reported by the developing authors of the DS from 0.62 to 0.73 (GA pain) and 0.64 to 0.70 (satisfaction with outcome). The calibration plots, however, revealed a low degree of concordance. For GA pain sensitivity varied from 92.4% to 99.3%, and specificity from 1.5% to 13.4%. For satisfaction, sensitivity varied from 97.1% to 99.2% and specificity from 0.0% to 2.9%. Conclusions: The predictive capabilities of the DS tool could not be generalized to the Danish sample cohorts. Further research on larger samples, provided full access to the underlying algorithms can be obtained, could produce a different result.

Applied Machine Learning for Spine Surgeons: Predicting Outcome for Patients Undergoing Treatment for Lumbar Disc Herniation Using PRO Data.

STUDY DESIGN: Retrospective/prospective study. OBJECTIVE: Models based on preoperative factors can predict patients' outcome at 1-year follow-up. This study measures the performance of several machine learning (ML) models and compares the results with conventional methods. METHODS: Inclusion criteria were patients who had lumbar disc herniation (LDH) surgery, identified in the Danish national registry for spine surgery. Initial training of models included 16 independent variables, including demographics and presurgical patient-reported measures. Patients were grouped by reaching minimal clinically important difference or not for EuroQol, Oswestry Disability Index, Visual Analog Scale (VAS) Leg, and VAS Back and by their ability to return to work at 1 year follow-up. Data were randomly split into training, validation, and test sets by 50%/35%/15%. Deep learning, decision trees, random forest, boosted trees, and support vector machines model were trained, and for comparison, multivariate adaptive regression splines (MARS) and logistic regression models were used. Model fit was evaluated by inspecting area under the curve curves and performance during validation. RESULTS: Seven models were arrived at. Classification errors were within ±1% to 4% SD across validation folds. ML did not yield superior performance compared with conventional models. MARS and deep learning performed consistently well. Discrepancy was greatest among VAS Leg models. CONCLUSIONS: Five predictive ML and 2 conventional models were developed, predicting improvement for LDH patients at the 1-year follow-up. We demonstrate that it is possible to build an ensemble of models with little effort as a starting point for further model optimization and selection.

Inter- and intrarater reliability of measuring lengthening of magnetically controlled growing rods on digital radiographs.

PURPOSE: The aim of this study was to determine inter- and intraobserver reliability of delta rod extension, and total rod length measured on digital x-rays in patients with early onset scoliosis (EOS) treated with magnetically controlled growing rods (MCGR). For the last decade, patients with EOS have been treated with MCGR. Replacement of MCGR relies heavily on the measurement done at every lengthening session. Only a few studies have looked at inter- and intraobserver reliability of rod lengthening, and none have used the delta extension before. METHODS: 202 radiographs presented in random order were rated and measured twice with at least a 14-day interval and differing order of the radiographs. The measuring was done at both rods. All x-rays came from 15 patients diagnosed with EOS and treated with MCGR from 2009 until 2019. The total extension length and the delta extension (the difference in total extension length between two lengthening in succession) were measured, and the intraclass correlation coefficient (ICC) calculated for both measurements RESULTS: Intrarater ICC scores varied from moderate to good, but non-significantly. Interrater reliability increased significantly from moderate (ICC 0.72 [0.68; 0.76] and 0.73 [0.69; 0.77] to excellent (ICC 0.91 [0.88; 0.93] and 0.97 [0.96: 0.98]), when examining delta extension every sixth instead of every second month. CONCLUSION: Measuring rod lengthening on x-rays can be done every 6 months, with an ample reliability. The ICC's for the delta extension with 2-3 months interval were only moderately precise, compared to the near perfect ICC's for the total extension length.

Comparison of interventions for lumbar disc herniation: a systematic review with network meta-analysis.

BACKGROUND: Implants for use in disc herniation surgery have been commercially available for some time. Several clinical trials have shown promising results. There are now a wide variety of surgical methods for treating lumbar disc herniation. PURPOSE: The objective of this systematic review was to compare all current surgical methods for disc herniation, including newer methods with implants for annulus repair and dynamic stabilization. STUDY DESIGN: Systematic review and network meta-analysis. METHODS: PRISMA-P guidelines were followed in this review. Literature search in PubMed, Embase, and Cochrane library databases identified eligible randomized controlled trials (RCT) studies comparing interventions for lumbar disc surgery. The investigated outcomes were: changes in pain score, disability score and reoperation rate with a minimum follow-up of 1 year. Risk of bias was assessed in concordance with Cochrane Neck and Back Review Group recommendation. A network meta-analysis was performed using gemtc and BUGSnet software, and each outcome evaluated using Confidence in Network Meta-Analysis (CINeMA). RESULTS: Thirty-two RCT studies, with 4,877 participants, and eight different interventions were identified. A significant difference was seen in change of pain score, as all treatments were superior to conservative treatment and percutaneous discectomy. This difference was only found to be of clinically importance when comparing conservative treatment and dynamic stabilization. There was no significant difference in reoperation rates or change in disability score, regardless of treatment. However, SUCRA plots showed a trend in ranking annulus repair and dynamic stabilization highest. Risk of bias assessment showed that 15 studies had a high overall risk of bias. Meta-regression with risk of bias as covariate did not indicate any influence in risk of bias on the model. Confidence in Network Meta-Analysis evaluation showed a high level of confidence for all treatment comparisons. CONCLUSIONS: With this network meta-analysis, we have aimed to compare all treatments for herniated lumbar disc in one large comprehensive systematic review and network meta-analysis. We have compared across the three main outcomes: disability score, pain score and reoperation rate. We were not able to rank one single treatment as the best. Most of the treatment performed at the same level. However percutaneous discectomy and conservative treatment consistently performed worse than the other treatments. In general, the CINeMA evaluation according to the GRADE recommendations gave a high level of confidence for the study comparisons.

Length of stay, readmission, and mortality after primary surgery for pediatric spinal deformities: a 10-year nationwide cohort study.

BACKGROUND CONTEXT: Extended length of stay (extLOS) and unplanned readmissions after first time pediatric spinal deformity surgery are a considerable challenge to both the patient and the health-care system. To our knowledge, only a limited number of nationwide studies reporting short-term comorbidity with complete follow-up exist. PURPOSE: The purpose of this study was to identify the postoperative complications leading to extLOS, readmissions, and mortality within 90 days after surgery. Furthermore, to identify risk factors for readmission. DESIGN: Retrospective national cohort study. PATIENT SAMPLE: A nationwide registry study including all pediatric spinal deformity patients (≤21 years of age) undergoing primary surgery during 2006-2015 (n=1,310). OUTCOME MEASURES: Reasons for extLOS and 90-day readmissions as well as mortality risk. METHODS: Patients were identified by procedure and diagnosis codes in the Danish National Patient Registry (DNPR). Data on length of stay (LOS), readmissions, and mortality within 90 days were retrieved from the DNPR. Patients were categorized in six groups according to etiology. Reasons for extLOS and readmission were collected from medical records and discharge summaries. RESULTS: For the 1,310 patients, the median LOS was 8 days (interquartile range 7-9). Etiologies were idiopathic deformity (53%), neuromuscular deformity (23%), congenital/structural deformity (9%), spondylolisthesis (7%), Scheuermann kyphosis (5%), and syndromic deformity (3%). A total of 274 (21%) patients had extLOS and the most common reason was pain/mobilization issues but with considerable variation between etiologies; Scheuermann kyphosis (91%), idiopathic (59%), syndromic (44%), spondylolisthesis (38%), and congenital (30%). Pulmonary complications were the primary reason for extLOS in the neuromuscular group (22%). The 90-day readmission rate was 6%; 67% of readmissions were medical, mainly infections unrelated to the surgical site (23%); 33% of readmissions were surgical and 14% of patients required revision surgery. Neuromuscular deformity, spondylolisthesis, Scheuermann kyphosis, and LOS >9 days were independent risk factors for readmission; odds ratio (OR) 4.4 (95% confidence interval: 2.2-9.1, p<.01), OR 3.0 (1.1-8.0, p=.03), OR 4.9 (1.7-13.6, p<.01), and OR 1.8 (1.0-3.1, p=.04), respectively. The 90-day mortality risk was 0.4%. CONCLUSIONS: In this nationwide cohort, pain/mobilization issues are the most common reason for extLOS. The most common reason for readmission is infection unrelated to the surgical site. Readmission after pediatric spinal surgery is related to the etiology and increased focus on patients operated for neuromuscular deformity, spondylolisthesis and Scheuermann kyphosis is warranted.

Revision risk after pediatric spinal deformity surgery: a nationwide study with 2-year follow-up.

BACKGROUND CONTEXT: Revision risk after pediatric spine surgery is not well established and varies between deformity etiologies. PURPOSE: To report the 2-year revision risk following surgery for primary pediatric spinal deformity in a nationwide cohort and to evaluate potential risk factors and reasons for revision surgery. DESIGN: Retrospective nationwide cohort study. PATIENT SAMPLE: A national registry study of all pediatric spinal deformity patients undergoing surgery during 2006-2015 (n=1310). OUTCOME MEASURES: Two-year revision risk. METHODS: All patients ≤21 years of age undergoing spinal deformity surgery in Denmark during 2006-2015 were identified by procedure and diagnosis codes in the Danish National Patient Registry (DNPR). Data on revision surgery were retrieved from the DNPR. Patients were categorized in six groups according to etiology. Medical records were reviewed for reason for revision in all patients. Potential risk factors for revision were assessed with multiple logistic regression analyses and included age, etiology, sex, Charlson comorbidity index (CCI), and growth-preserving treatment. RESULTS: Patients were categorized according to etiology: idiopathic deformity (53%), neuromuscular deformity (23%), congenital/structural deformity (9%), spondylolisthesis (7%), Scheuermann's kyphosis (5%), and syndromic deformity (3%). Of 1,310 included patients, 9.2% underwent revision surgery within 2 years and 1.5% was revised more than once. Median time to revision was 203 (interquartile range 35-485) days. The multivariable logistic regression found significantly higher odds ratio (OR) for revision in patients with growth-preserving treatment (OR=5.1, 95% confidence interval [CI] 2.6-10.1), congenital deformity (OR=2.7, 95% CI 1.3-5.3), spondylolisthesis (OR=3.5, 95% CI 1.9-6.7), Scheuermann kyphosis (OR=3.9, 95% CI 1.9-8.3), and CCI score ≥3 (OR=2.5 95% CI 1.1-5.6). The most common reason for revision was implant failure (32.5%) followed by residual deformity and/or curve progression (15.8%). CONCLUSIONS: In this nationwide study, the 2-year revision risk after primary pediatric spinal deformity surgery is 9.2%. Risk factors for revision are etiology of congenital deformity, spondylolisthesis, Scheuermann kyphosis as well as patients with growth-preserving treatment and higher CCI. The most common reason for revision is implant failure.

Magnetically controlled growing rods in early-onset scoliosis.

INTRODUCTION: Early-onset scoliosis (EOS) may result in disability and a reduced life expectancy. The aim of this study was to report the results of primary magnetically controlled growing rods (MCGR) in a consecutive group of patients with EOS diagnosed and operated at Aalborg University Hospital, Denmark, from 2009 and onwards and with at least two years of follow-up. METHODS: Data were extracted from the electronic patient records and the Picture Archiving and Communication System. All data were extracted by an unbiased observer. Demographics, any complication and the Cobb angles and maximal kyphosis angles preoperatively and post-operatively were recorded. Likewise, the total expansion of the MCGR and the increase in T1-T12 and T1-S1 heights were recorded. RESULTS: A total of 15 patients (three females) were followed for an average of 3.75 years. The Cobb angles were corrected on average by 68% and the maximal kyphosis angle by 45%. The thoracic height increased significantly with only two patients (still undergoing expansions) with a T1-S1 height below 22 cm. Four complications were recorded (one deep infection and three non-functioning rods), all resulting in rod exchange. The complication rate was 27% or 0.07 per patient per year. CONCLUSIONS: The MCGR may reduce the deformity and support thoracic and pulmonary growth without any need for repeated surgeries. The number of complications in the present series was low compared with the literature with an average of 0.07 complications per year per patient or a total complication rate of 27%. FUNDING: none. TRIAL REGISTRATION: not relevant.

HOW MANY DOSEMETERS ARE NEEDED FOR CORRECT MEAN ORGAN DOSE ASSESSMENT WHEN PERFOMING PHANTOM DOSIMETRY? A PHANTOM STUDY EVALUATING LIVER ORGAN DOSE AND INVESTIGATING TLD NUMBERS AND WAYS OF DOSEMETER PLACEMENT.

This study evaluated repeated mean organ dose measurements of the liver by phantom dosimetry and statistical modelling in order to find a way to reduce the number of dosemeters needed for precise organ dose measurements. Thermoluminescent dosemeters were used in an adult female phantom exposed to a biplanar x-ray source at three different axial phantom rotations. Generalised mixed linear effect modelling was used for statistical analysis. A subgroup of five to six organ-specific locations out of 28 yielded mean liver organ doses within 95% confidence intervals of measurements based on all 28 liver-specific dosemeter locations. No statistical difference of mean liver dose was observed with rotation of the phantom either 10° clockwise or counter-clockwise as opposed to the coronal plane. Phantom dosimetry handling time during organ dose measurements can be markedly reduced, in this case the liver, by 79% (22/28), while still providing precise mean organ dose measurements.

Vertebral Osteomyelitis: A Mortality Analysis Comparing Surgical and Conservative Management.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To compare the mortality between patients treated for vertebral osteomyelitis (VO) with either surgical or conservative management and to construct a predictive model for mortality after VO. METHODS: All patients with a diagnosis of VO in Region North Denmark from 2004 to 2014 were followed for at least 2 years or until death. They were all treated according to a standardized guideline for the choice of treatment modality. Nineteen dichotomized variables with possible influence on the mortality were registered for all patients in the study. LASSO (least absolute shrinkage and selection operator) penalized Cox regression analysis was used to build a predictive model for 2-year survival after VO. RESULTS: A total of 125 patients were eligible for inclusion, mean age 67 years, 36 women. 75 were treated surgically. Twenty-one patients were dead 2 years after the diagnosis. Kaplan-Meier estimate of 2-year survival was 0.82 [0.75, 0.88]. Any difference in mortality between surgically and conservatively treated patients was nonsignificant at 1 and 2 years (univariate Cox regression analysis). Significant factors included in the predictive model after LASSO penalized Cox regression analysis was Charlson Comorbidity Index (CCI), cardiovascular disease, C-reactive protein (CRP) normalization, thoracic infection, and Karnofsky score. The area under the curve (AUC) for the predictive model ranged from 0.74 to 0.77. CONCLUSION: Patients undergoing surgical management for vertebral osteomyelitis according to standardized and agreed-upon guidelines had no higher mortality than those allocated to conservative treatment. The predictive model included 5 variables associated with an increased mortality: CCI, CRP normalization, cardiovascular disease, thoracic infection, and Karnofsky score.

Cumulative radiation exposure during current scoliosis management.

INTRODUCTION: Patients undergoing scoliosis management are exposed to repeated radiological imaging. Previous studies have shown an increase in incidence of cancer among these patients. The primary aim of this study was to evaluate the radiographic examinations and cumulative radiation dose to which scoliotic patients are exposed. A secondary aim was to compare in-house algorithms of scoliosis management and radiographic follow-up to international spine centres and current consensus literature. MATERIALS AND METHODS: A single-centre retrospective review evaluating type and frequency of radiographic imaging and total cumulative radiation exposure to patients treated for scoliosis. Inclusions: patients followed for idiopathic scoliosis in the years 2013-2016. A survey asking for information on management and radiological follow-up algorithms was sent to a number of international spine centres for comparison with the in-house algorithm. RESULTS: Patients who underwent surgery received an approximately ten-fold higher median cumulative radiation dose than those treated conservatively. A variety of radiological follow-up algorithms among eight spine centres was observed. CONCLUSIONS: Cumulative radiation dose during scoliosis treatment varies substantially depending on radiographic follow-up protocol, intraoperative and ancillary imaging. By using low-dose X-ray systems in combination with a low-dose protocol for intraoperative navigation, it is possible to keep exposure to patients at a minimum while still providing optimal care. FUNDING: none. TRIAL REGISTRATION: not relevant.

Surgical Treatment of Degenerative Disk Disease in Three Scandinavian Countries: An International Register Study Based on Three Merged National Spine Registers.

STUDY DESIGN: Observational study of prospectively collected data. OBJECTIVES: Patients with chronic low back pain resistant to nonoperative treatment often face a poor prognosis for recovery. The aim of the current study was to compare the variation and outcome of surgical treatment of degenerative disc disease in the Scandinavian countries based on The International Consortium for Health Outcomes Measurement core spine data sets. METHODS: Anonymized individual level data from 3 national registers were pooled into 1 database. At the time of surgery, the patient reports data on demographics, lifestyle topics, comorbidity, and data on health-related quality of life such as Oswestry Disability Index, Euro-Qol-5D, and back and leg pain scores. The surgeon records diagnosis, type of surgery performed, and complications. One-year follow-ups are obtained with questionnaires. Baseline and 1-year follow-up data were analyzed to expose any differences between the countries. RESULTS: A total of 1893 patients were included. At 1-year follow-up, 1315 (72%) patients responded. There were statistically significant baseline differences in age, smoking, comorbidity, frequency of previous surgery and intensity of back and leg pain. Isolated fusion was the primary procedure in all the countries ranging from 84% in Denmark to 76% in Sweden. There was clinically relevant improvement in all outcome measures except leg pain. CONCLUSIONS: In homogenous populations with similar health care systems the treatment traditions can vary considerably. Despite variations in preoperative variables, patient reported outcomes improve significantly and clinically relevant with surgical treatment.

A Nano-Dose Protocol For Cobb Angle Assessment in Children With Scoliosis: Results of a Phantom-based and Clinically Validated Study.

STUDY DESIGN: This was a prospective validation study with technical notes. OBJECTIVE: This study aimed to validate a new ultra-low-dose full-spine protocol for reproducible Cobb angle measurements-the "nano-dose" protocol. SUMMARY OF BACKGROUND DATA: Scoliosis is a 3-dimensional (3D) deformity of the spine characterized by 3D clinical parameters. Nevertheless, 2D Cobb angle remains an essential and widely used radiologic measure in clinical practice. Repeated imaging is required for the assessment and follow-up of scoliosis patients. The resultant high dose of absorbed radiation increases the potential risk of developing radiation-induced cancer in such patients. Micro-dose radiographic imaging is already available in clinical practice, but the radiation dose delivered to the patient could be further reduced. METHODS: An anthropomorphic child phantom was used to establish an ultra-low-dose protocol in the EOS Imaging System still allowing Cobb angle measurements, defined as nano-dose. A group of 23 consecutive children presenting for scoliosis assessment, 12 years of age or younger, were assessed with standard-dose or micro-dose and additional nano-dose full-spine imaging modalities. Intraobserver and interobserver reliability of determining the reliability of 2D Cobb angle measurements was performed. The dosimetry was performed in the anthropomorphic phantom to confirm theoretical radiation dose reduction. RESULTS: A nano-dose protocol was established for reliable Cobb angle measurements. Dose area product with this new nano-dose protocol was reduced to 5 mGy×cm, corresponding to one sixth of the micro-dose protocol (30 mGy×cm) and <1/40th of the standard-dose protocol (222 mGy×cm). Theoretical dose reduction, for posteroanterolateral positioning was confirmed using phantom dosimetry. Our study showed good reliability and repeatability between the 2 groups. Cobb variability was <5 degrees from the mean using 95% confidence intervals. CONCLUSIONS: We propose a new clinically validated nano-dose protocol for routine follow-up of scoliosis patients before surgery, keeping the radiation dose at a bare minimum, while allowing for reproducible Cobb angle measurements.

Lumbar spinal stenosis: comparison of surgical practice variation and clinical outcome in three national spine registries.

BACKGROUND CONTEXT: Decompression surgery for lumbar spinal stenosis (LSS) is the most common spinal procedure in the elderly. To avoid persisting low back pain, adding arthrodesis has been recommended, especially if there is a coexisting degenerative spondylolisthesis. However, this strategy remains controversial, resulting in practice-based variation. PURPOSE: The present study aimed to evaluate in a pragmatic study if surgical selection criteria and variation in use of arthrodesis in three Scandinavian countries can be linked to variation in treatment effectiveness. STUDY DESIGN: This is an observational study based on a combined cohort from the national spine registries of Norway, Sweden, and Denmark. PATIENT SAMPLE: Patients aged 50 and older operated during 2011-2013 for LSS were included. OUTCOME MEASURES: Patient-Reported Outcome Measures (PROMs): Oswestry Disability Index (ODI) (primary outcome), Numeric Rating Scale (NRS) for leg pain and back pain, and health-related quality of life (Euro-Qol-5D) were reported. Analysis included case-mix adjustment. In addition, we report differences in hospital stay. METHODS: Analyses of baseline data were done by analysis of variance (ANOVA), chi-square, or logistic regression tests. The comparisons of the mean changes of PROMs at 1-year follow-up between the countries were done by ANOVA (crude) and analysis of covariance (case-mix adjustment). RESULTS: Out of 14,223 included patients, 10,890 (77%) responded at 1-year follow-up. Apart from fewer smokers in Sweden and higher comorbidity rate in Norway, baseline characteristics were similar. The rate of additional fusion surgery (patients without or with spondylolisthesis) was 11% (4%, 47%) in Norway, 21% (9%, 56%) in Sweden, and 28% (15%, 88%) in Denmark. At 1-year follow-up, the mean improvement for ODI (95% confidence interval) was 18 (17-18) in Norway, 17 (17-18) in Sweden, and 18 (17-19) in Denmark. Patients operated with arthrodesis had prolonged hospital stay. CONCLUSIONS: Real-life data from three national spine registers showed similar indications for decompression surgery but significant differences in the use of concomitant arthrodesis in Scandinavia. Additional arthrodesis was not associated with better treatment effectiveness.

Effectiveness of surgery for sciatica with disc herniation is not substantially affected by differences in surgical incidences among three countries: results from the Danish, Swedish and Norwegian spine registries.

PURPOSE: Yearly incidence of surgery for symptomatic lumbar disc herniation varies and is 29/100,000 in Sweden, 46/100,000 in Denmark and 58/100,000 in Norway. This variation was used to study whether differences in surgical incidence were associated with differences in preoperative patient characteristics as well as patient-reported outcomes. METHODS: Data from the national spine registers in Sweden, Denmark and Norway during 2011-2013 were pooled, and 9965 individuals, aged 18-65 years, of which 6468 had one-year follow-up data, were included in the study. Both absolute and case-mix-adjusted comparisons of the primary outcome Oswestry Disability Index (ODI) and the secondary outcomes EQ-5D-3L, and Numerical Rating Scale (NRS) for leg and back pain were performed. Case-mix adjustment was done for baseline age, sex, BMI, smoking, co-morbidity, duration of leg pain and preoperative value of the dependent variable. RESULTS: Mean improvement in the outcome variables exceeded previously described minimal clinical important change in all countries. Mean (95% CI) final scores of ODI were 18 (17-18), 19 (18-20) and 15 (15-16) in Sweden, Denmark and Norway, respectively. Corresponding results of EQ-5D-3L were 0.74 (0.73-0.75), 0.73 (0.72-0.75) and 0.75 (0.74-0.76). Results of NRS leg and back pain behaved similarly. Case-mix adjustment did not alter the findings substantially. CONCLUSION: We found no clear association between incidence of surgery for lumbar disc herniation and preoperative patient characteristics as well as outcome, and the differences between the countries were lower than the minimal clinical important difference in all outcomes. These slides can be retrieved under Electronic Supplementary Material.