Bisphosphonate-loaded bone cement: Background, clinical indications and future perspectives.

Bisphosphonates represent an established treatment against bone resorption and osseous loss. Local application could help increase bone mineral density while minimizing their systemic use side-effects. Bone cement, used on a large scale in orthopedic surgery and a historically successful drug carrier, could represent an effective scaffold. The aim of this review was to investigate the alterations produced on the cement's structure and properties by this mixture, as well as its antiosteoporotic and antitumor effect. After a thorough research of articles, title screening and duplicate removal we retained 51 papers. Two independent authors performed abstract and full-text reading, finally leaving 35 articles included in this review. In the current literature, acrylic and calcium phosphate bone cement have been used as carriers. A combination with nitrogen-containing bisphosphonates, e.g., zoledronic acid, provokes modifications in terms of setting time prolongation and mechanical strength decline within acceptable levels, on the condition that the drug's quantity stays beneath a certain plateau. Bisphosphonates in bone cement seem to have a powerful anti-osteoclastic and osteogenic local impact as well as a direct cytotoxic effect against several neoplastic lesions. Further investigation on the subject is required, with specifically designed studies focusing on this method's advantages and potential clinical applications.

Surgical timing in traumatic spinal cord injury: current practice and obstacles to early surgery in Latin America.

STUDY DESIGN: Cross-sectional. OBJECTIVES: To evaluate current practice of Latin American spine surgeons regarding surgical timing in patients with traumatic spinal cord injury (tSCI) and to identify potential barriers for early surgery. SETTING: Web-based. METHODS: A web-based questionnaire was sent to members of AOSpine Latin America. Questions involved demographic features, familiarity with management of tSCI, and timing of surgery in various tSCI scenarios. The participants were also asked if they would like to operate earlier on patients with tSCI, indicating potential obstacles to early surgery. RESULTS: A total of 307 surgeons answered the questionnaire. Early surgery (<24 h) is performed by 66.8% for ASIA A, 76.9% for ASIA B, and 76.9% for ASIA C/D injuries. For traumatic cauda equina syndrome (tCES), 85.2% performed surgery within 24 h. For traumatic central cord syndrome (tCCS) without osteoligamentous instability, only 31.5% performed surgery within 24 h and 41.2% follow-up on these patients, indicating surgery if no symptom improvement. Early surgery was performed always or in most cases by 50.4% and 41.8% of surgeons for incomplete and complete tSCI, respectively. The majority (85.4%) would like to operate earlier on patients with tSCI than they actually do. The most frequently perceived barriers to early surgery were difficulty of access to surgical implants (70.9%) and delay in patient transport to reference hospital for surgery (57.8%). CONCLUSION: Latin American spine surgeons tend to operate earlier on patients with tCES and incomplete tSCI, then on those with complete tSCI and tCCS. The most reported obstacles for early surgery involved healthcare resources.

Lumbar disc herniation with contralateral radiculopathy: a systematic review on pathophysiology and surgical strategies.

Lumbar disc herniation (LDH) is a relatively common pathology usually presenting with unilateral radiculopathy ipsilateral to the disc herniation. Some patients can present with contralateral radicular symptoms. The objective of this article is to review the current literature on lumbar disc herniations with contralateral radiculopathy regarding its pathophysiology and surgical strategies. A systematic review of the literature on LDH with contralateral radiculopathy was performed using MEDLINE (via PubMed) using MeSH terms. This review was done following recommendations of PRISMA statement and PICOT strategy of search. Initial electronic search identified 126 papers. Finally, 18 articles were reviewed. None of the included papers was described as comparative. Pathophysiological processes underlying contralateral pain may include prominent spondylotic changes and the accompanying stenosis; hypertrophic yellow ligament; dural attachments along the posterior longitudinal ligament; nerve root traction forces; and friction radiculitis, migrated epidural fat, nerve root anomaly, and venous congestion inside the vertebral canal. In our pooled analysis, 11 patients reported were treated by bilateral approach with 100% of clinical success and no complications. Eight patients were treated by unilateral approach ipsilateral to pain with 100% of clinical success and no complications. Forty-eight patients were treated by unilateral approach ipsilateral to herniation with 100% of clinical success and no complications. Pathophysiology underlying contralateral pain in LDH is probably multifactorial. There is not enough scientific evidence to define the best surgical approach for patients with LDH and contralateral pain.

Vertebral body fracture after anterior cervical discectomy and fusion with zero-profile anchored cages in adjacent levels: a cautionary tale.

BACKGROUND CONTEXT: Zero-profile (also called self-locking, anchored or stand-alone cages) have been recently proposed as an interesting alternative for anterior cervical discectomy and fusion (ACDF), as they are supposed to reduce the rates of post-operative cage extrusion without necessarily incurring in the additional surgical time and increased rates of dysphagia associated with plating. Nevertheless, the exact indications of zero-profile anchored cages have not yet been established in the literature. PURPOSE: To report the first case of a vertebral body fracture between the blades of zero-profile anchored cages after ACDFs in adjacent levels and to review the available literature on hardware-related complications after multi-level ACDFs with zero-profile anchored cages. STUDY DESIGN: Case report and systematic literature review. METHODS: The authors report the first case of a vertebral body fracture between the blades of zero-profile anchored cages after ACDFs in adjacent levels. The patient presented with refractory mechanical neck pain at the 1-month post-operative follow-up, ultimately requiring a posterior instrumented fusion. A comprehensive systematic literature review on the available data regarding the safety, complications as well as radiological and clinical outcomes of zero-profile anchored cages is also performed. RESULTS: In the reported case, the use of zero-profile anchored cages in adjacent levels on the cervical spine led to a fracture of the vertebral body between the cages at the 1-month follow-up, with anterior avulsion of the part of the vertebral body where the blades from the two cages converged. According to the systematic literature review which included 409 patients from 10 different clinical series (with a total cumulative follow-up of approximately 535 patients-year), there were only two reported hardware-related complications after ACDF with zero-profile anchored cages, none of them involving fracture at the level of convergence of blades or screws. CONCLUSIONS: Although hardware-related complications after the use of zero-profile anchored cages seem to be rare events, future biomechanical and clinical studies are warranted in order to evaluate the safety of employing such devices for the treatment of multilevel degenerative disc disease in the cervical spine.

Back pain in adolescents with idiopathic scoliosis: the contribution of morphological and psychological factors.

PURPOSE: To define the relationship between 3D radiological features, psychological factors, and back pain prevalence and intensity in patients with adolescent idiopathic scoliosis (AIS). METHODS: Consecutive AIS patients answered self-reported questionnaires and underwent simultaneous posterior-anterior and lateral scans of the spine (EOS Imaging, Paris, France). 3D reconstructions of the spine and pelvis reported 18 parameters in the coronal, sagittal, and axial plane. RESULTS: Hundred and twenty-four patients with AIS were included in the study. Overall, 90% of AIS patients reported having some back pain over the last 6 months and 85.8% over the last 30 days. Pain intensity in the last month was reported to be mild in 37.5%, moderate in 31.8%, moderate to severe in 24.3%, and severe in 6.54% of cases. Location of back pain was associated with location of main curve (P = 0.036). Low back pain was associated with higher lumbar apical AVR and lower lumbar lordosis (P < 0.05). Independent risk factors for back pain in AIS were pain catastrophizing (B = 0.061, P = 0.035), poorer self-reported state of mental health (B = - 0.872, P = 0.023), decreased thoracic kyphosis (B = - 0.033, P = 0.044) and greater pelvic asymmetry (B = 0.146, P = 0.047). There was a significant association between self-reported pain intensity in the last 24 h and levels of catastrophizing. Pain catastrophizing level influenced the relationship between deformity severity and pain intensity. In low catastrophizers, there was a significant association between greater deformity severity and higher pain levels. CONCLUSIONS: Back pain in AIS is multifactorial and associated with psychological and morphological parameters. Pain catastrophizing is an important construct in AIS-related pain and should be taken into consideration when evaluating these patients.

Adolescent idiopathic scoliosis: evaluating perioperative back pain through a simultaneous morphological and biomechanical approach.

BACKGROUND: Adolescent idiopathic scoliosis (AIS) has been associated with diminished postural stability and a greater prevalence of back pain. Currently, the literature is lacking information on the effect of spinal fusion on both postural stability and its association with back pain. Our objectives were to evaluate the postsurgical effect of spinal morphological changes on static standing balance and assess the influence of these alterations on reported pain throughout the perioperative period. METHODS: Twenty consecutive AIS patients schedule to undergo spinal fusion surgery were recruited and followed prospectively at the Shriners Hospitals for Children-Canada. Data was collected at the preoperative, 6 weeks and 6 months postoperative visits. Spinal morphology data was collected through 3D reconstructed simultaneous standing biplanar radiographs using the SterEOS software. Postural balance was assessed through Moticon© sensor insoles and analyzed through their software. The data was simultaneously collected as part of the Global Biomechanical and morphological Assessment. Pain was evaluated through self-reported questionnaires. RESULTS: Morphological curve parameters were significantly reduced after surgery. Balance parameters did not change significantly throughout the perioperative period with the exception of the Center of Pressure of the left foot medial/lateral transient shift (P = 0.017) at 6 weeks. Of note, preoperative balance parameters were associated with the degree of right thoracic Cobb angles (P = 0.029 R = 0.528). Pain scores significantly improved 6 weeks and 6 months after the surgery. Pain intensity diminished in the thoracic and lumbar spine but worsen in the neck region at the 6 weeks and 6 months postoperative time points (P = 0.044). Greater residual Cobb angle difference between Mid thoracic and Thoracolumbar/Lumbar curves was associated with greater pain severity at 6 weeks postop (P < 0.005). In addition, greater residual thoracic deformity was associated with significant pain severity 6 months after surgery (P < 0.05). CONCLUSIONS: Improved spinal morphology of postsurgical AIS patients has no significant impact on their static standing balance. Suggesting that other factors apart from the spinal morphology may contribute to AIS patients' balance during stance. Although balance did not influence pain severity, spinal morphology and its correction appear to have influenced the intensity and location of back pain.

The 'Lumbar Fusion Outcome Score' (LUFOS): a new practical and surgically oriented grading system for preoperative prediction of surgical outcomes after lumbar spinal fusion in patients with degenerative disc disease and refractory chronic axial low back pain.

In order to evaluate the predictive effect of non-invasive preoperative imaging methods on surgical outcomes of lumbar fusion for patients with degenerative disc disease (DDD) and refractory chronic axial low back pain (LBP), the authors conducted a retrospective review of 45 patients with DDD and refractory LBP submitted to anterior lumbar interbody fusion (ALIF) at a single center from 2007 to 2010. Surgical outcomes - as measured by Visual Analog Scale (VAS/back pain) and Oswestry Disability Index (ODI) - were evaluated pre-operatively and at 6 weeks, 3 months, 6 months, and 1 year post-operatively. Linear mixed-effects models were generated in order to identify possible preoperative imaging characteristics (including bone scan/99mTc scintigraphy increased endplate uptake, Modic endplate changes, and disc degeneration graded according to Pfirrmann classification) which may be predictive of long-term surgical outcomes . After controlling for confounders, a combined score, the Lumbar Fusion Outcome Score (LUFOS), was developed. The LUFOS grading system was able to stratify patients in two general groups (Non-surgical: LUFOS 0 and 1; Surgical: LUFOS 2 and 3) that presented significantly different surgical outcomes in terms of estimated marginal means of VAS/back pain (p = 0.001) and ODI (p = 0.006) beginning at 3 months and continuing up to 1 year of follow-up. In conclusion,  LUFOS has been devised as a new practical and surgically oriented grading system based on simple key parameters from non-invasive preoperative imaging exams (magnetic resonance imaging/MRI and bone scan/99mTc scintigraphy) which has been shown to be highly predictive of surgical outcomes of patients undergoing lumbar fusion for treatment for refractory chronic axial LBP.

Modern surgical techniques for management of soft tissue sarcomas involving the spine: outcomes and complications.

Several types of soft tissue sarcomas may locally extend to the spine. The best therapeutic strategy for such lesions strongly depends on the histological diagnosis. In this article the authors provide an up-to-date review of current guidelines regarding the management of soft tissue sarcomas involving the spine. Special attention is given to outcomes and complications of modern surgical series in order to highlight current challenges in the management of such lesions.

Mechanical Complications in Adult Spinal Deformity Surgery: Can Spinal Alignment Explain Everything?

STUDY DESIGN: Cohort study. OBJECTIVE: Our goal was to verify the validity of the global alignment and proportion (GAP) score, SRS-Schwab, and Roussouly theoretical apex of lordosis in predicting mechanical complications in adult spinal deformity (ASD). SUMMARY OF BACKGROUND DATA: Achieving adequate sagittal alignment is critical to obtain favorable outcomes in ASD surgery. It has been proposed that mechanical complications are largely secondary to postoperative spinal alignment. METHODS: Retrospective review of consecutive primary ASD cases that underwent deformity correction in the same institution over a 5-year period. Association between the 6-week postoperative spinal alignment classification and occurrence of mechanical complications on the last follow-up was assessed using logistic regressions. The discriminant capacity was assessed using the receiver operating characteristic (ROC) curve analysis. RESULTS: 58.3% (N = 49/84) of patients presented with mechanical complications and 32.1% (N = 27/84) underwent revision surgery. GAP score did not show discriminant ability to predict complications (AUC = 0.53, 95% confidence interval [CI] = 0.40-0.66, P = 0.58). Conversely, the SRS-Schwab sagittal modifier score demonstrated a statistically significant (although modest) predictive value for mechanical complications (AUC = 0.67, 95% CI = 0.54-0.79, P = 0.008). There was a significant association between pelvic tilt (PT) (P = 0.03) and sagittal vertical axis (SVA) (P = 0.01) at 6 weeks postoperatively and the occurrence of later mechanical complications. There was no significant association between matched Roussouly theoretical apex of lordosis and final outcome (P = 0.47). CONCLUSION: The results point to the complexity of mechanical failure and the high likelihood that causative factors are multifactorial and not limited to alignment measures. GAP score should be used with caution as it may not explain or predict mechanical failure based on alignment in all populations as originally expected. Future studies should focus on etiology, surgical technique, and patient factors in order to generate a more universal score that can be applied to all populations.Level of Evidence: 4.

Spine Surgeons Burnout and Quality of Life: Results of a Worldwide Survey.

STUDY DESIGN: Cross-sectional survey study. OBJECTIVE: To evaluate the prevalence of burnout, assess the personal and professional characteristics associated with burnout in spine surgeons and determine their quality of life. SUMMARY OF BACKGROUND DATA: Burnout is a syndrome characterized by emotional exhaustion, depersonalization, and decreased sense of accomplishment that leads to decreased effectiveness at work. To date, there has been a lack of information on the prevalence of burnout among spine surgeons worldwide and the risk factors associated with this condition. METHODS: An electronic survey with members of AO Spine was performed in May 2018. The survey evaluated demographic variables, practice characteristics, burnout, and quality of life. Maslach Burnout Inventory (MBI) and EuroQol 5-dimensions (EQ5D) were used to evaluate burnout and quality of life, respectively. RESULTS: A total of 818 surgeons from 86 countries completed the survey. The prevalence of burnout was 30.6%. In the multiple linear model, emotional fatigue was independently associated with younger age (B = -0.17, CI95% = -0.26 to -0.07, P < 0.0001), and longer working hours per week (B = -2.71, CI95% = -4.34 to -1.07, P = 0.001); depersonalization was independently associated with younger age (B = -0.13, CI95% = -0.19 to -0.07, P < 0.0001), practicing outside Latin America (LA) (B = 0.71, CI95% = 0.41-1.01, P < 0.0001) and currently being a fellow (B = 0.54, CI95% = 0.06-1.02, P = 0.02); and higher scores of personal fulfilment was associated with practicing in LA (B = -1.27, CI95% = -1.69 to -0.85, P < 0.0001). CONCLUSION: Burnout is a common condition among spine surgeons worldwide. There is a significant association between burnout scores and decreased general quality of life. These results highlight the need to develop interventional programs to better identify, prevent, and manage this condition among practicing spine surgeons.Level of Evidence: 4.

Management of Unilateral Cervical Facet Joint Dislocation in Neurologically Intact Patients: Results of an Ao Spine latin American Survey.

BACKGROUND: The treatment of unilateral CFD in patients without neurologic deficits remains controversial, especially in the choice of the best surgical approach. Our objective is to determine the way spine surgeons from Latin America manage this condition. METHODS: A survey regarding management and surgical strategies was conducted by the AO Spine Latin American Trauma Study Group considering the treatment of unilateral CFD. RESULTS: All AO Spine Latin American Trauma Study Group members were sent a link to the survey, among whom 285 replied, with 197 respondents answering all the questions. Nonsurgical management was considered by 25% of the surgeons. The majority stated that magnetic resonance imaging is necessary (65%) to treat this type of patient. A posterior approach was preferred by 44%, an anterior approach by 29%, and a combined approach by 25%, while 2.2% did not answer. Traction was not used by the majority of respondents (62%). In the setting of an anterior disk herniation, the majority of surgeons preferred to employ an anterior (45%) or combined (44%) approach versus an isolated posterior approach (only 0.5%). Comparing early versus late cervical trauma, fewer surgeons adopted an isolated anterior approach with the latter (29% vs. 15%). CONCLUSIONS: Wide variations exist in the management of unilateral CFD by Latin American surgeons, with early injuries generally treated using either an anterior or posterior approach and treated early but after an MRI, while a combined approach is used more commonly with late injuries. Either an anterior or combined approach is used when disk herniation is present.

Intraosseous sacral paraganglioma with extradural extension: case report.

BACKGROUND: Paragangliomas are tumors that arise from the paraganglion system, which is a component of the neuroendocrine system. Approximately 10% are located in the extra-adrenal paraganglion system. Paragangliomas of the spine, however, are rare. They usually present as an intradural tumor in the cauda equina. There are only three reports of primary intraosseous paragangliomas of the sacrum. CASE DESCRIPTION: A 69-year-old man presented with low back pain and urinary incontinence. Imaging revealed a large intraosseous mass at S2, S3 and S4. Surgical resection was accomplished through a posterior midline incision exposing the spine from L5 to the coccyx. The tumor was located in the extradural space. It was friable, grayish and bleeding. Total tumor removal was performed, with normal bone margins. Follow-up at 2 years showed complete resolution of the preoperative symptoms and no evidence of local recurrence. CONCLUSION: Although rare, the possibility of paraganglioma should be included in the differential diagnosis of sacral tumors. The majority of the spinal paragangliomas are benign, slowly growing tumors with low proliferative activity. Despite these characteristics, local recurrence has been reported in cases of both macroscopically total and subtotal resection. Postoperative radiation therapy for patients with incomplete excision may not prevent recurrence, so gross tumor removal should be the goal of surgery.

Pedicle Screw Instrumentation in Scoliosis Surgery: On Site Simulation Data on Accuracy and Efficiency With Different Techniques.

STUDY DESIGN: Prospective experimental study with on-site simulation. OBJECTIVE: To compare the accuracy and efficiency of different techniques for pedicle screw instrumentation (PSI). SUMMARY OF BACKGROUND DATA: Improving the safety and efficiency of PSI is a critical step to reduce the complication rates and the cost of scoliosis surgery. Innovative operative techniques for PSI have shown to safely improve efficiency, thereby reducing cost. Surgical simulation is a valuable tool to study different operative techniques. METHODS: Five spine fellows instrumented 20 simulation models of a scoliotic spine with 10 pedicle screws per model. Four techniques were studied, including the conventional pedicle probe and the innovative sequential drilling technique, with or without computed tomography (CT)-based navigation. Our primary outcome measures were efficiency and accuracy of PSI. We analyzed the data with bivariate analyses using the Chi-square test for categorical variables and the Student t test or ANalysis Of VAriance with Bonferroni post-hoc tests for continuous variables. RESULTS: The drilling techniques (free hand and navigated) were more efficient as compared with the pedicle probe techniques (P < 0.01). The navigated techniques resulted in better accuracy as compared with the free hand techniques (P = 0.036). Most pedicle breaches were medial (n = 32/52). The concave apical pedicle (T4 right side) had the highest incidence of breaches. There was no significant difference in efficiency comparing the free hand and the navigated pedicle probe techniques (P = 0.261) or comparing the free hand drilling and the navigated drilling techniques (P = 1.00). CONCLUSION: On site surgical simulation is a promising concept for teaching advanced procedural skills. Our findings suggest that navigation improves the accuracy of PSI while sequential drilling safely improves efficiency. Combining navigation with sequential drilling can significantly improve the accuracy and the efficiency of PSI in scoliosis surgery, as previously suggested with our published clinical data. LEVEL OF EVIDENCE: 4.

Publication rate of abstracts presented at the annual meetings of the AANS/CNS Section on Disorders of the Spine and Peripheral Nerves.

OBJECTIVE: The objective of this study was to determine the publication rate of abstracts presented at the annual meetings of the AANS/CNS Section on Disorders of the Spine and Peripheral Nerves (Spine Summit). METHODS: The authors used a search algorithm in PubMed to determine the publication rate of abstracts presented at the Spine Summit from 2007 to 2012. The variables assessed were presentation modality, topic, meeting year, publication year, destiny journal and its 5-year impact factor (IF), country, and citation count (retrieved from the Scopus database). RESULTS: One thousand four hundred thirty-six abstracts were analyzed; 502 were oral presentations and 934 were digital poster presentations. The publication rate was 53.97% (775/1436). The mean time from presentation to publication was 1.35 ± 1.97 years (95% CI 1.21-1.49 years). The mean citation count of published articles was 40.55 ± 55.21 (95% CI 36.66-44.44). Oral presentations had a higher publication rate (71.51%, 359/502) than digital posters (44.54%, 416/934; OR 3.13, 95% CI 2.48-3.95, p < 0.001). Oral presentations had a higher number of citations (55.51 ± 69.00, 95% CI 48.35-62.67) than digital posters (27.64 ± 34.88, 95% CI 24.28-31.00, p < 0.001). The mean IF of published articles was 3.48 ± 2.91 (95% CI 3.27-3.70). JNS: Spine (191/775, 24.64%), Spine (103/775, 13.29%), and Neurosurgery (56/775, 7.23%) had the greatest number of published articles. The US represented the highest number of published articles (616/775, 79.48%). CONCLUSIONS: The publication rate of the Spine Summit is among the highest compared to other spine meetings. Many of the abstracts initially presented at the meeting are further published in high-IF journals and had a high citation count. Therefore, the Spine Summit maintains its high standards of scientific papers, which reflects the high quality of the research performed in the spine surgery field in North America.

Necrotizing Fasciitis Involving Spine: Unusual Medical Emergency for Spine Surgeon.

BACKGROUND: Necrotizing fasciitis (NF) is a surgical diagnosis characterized by a rapidly progressive soft tissue infection, widespread tissue necrosis, and associated systemic illness. Friability of the superficial fascia, dishwater-gray exudate, and absence of pus are surgical characteristics of this diagnosis. Due to rapid progression of the infection, early recognition and aggressive surgical debridement are crucial to reduce mortality. Despite being commonly seen by general, plastic, and orthopedic surgeons, NF is an extremely rare spine surgery emergency. Our objective is to report on a case of NF involving the spine and highlight this unusual surgical emergency for the spine surgeon. CASE DESCRIPTION: We present a rare case of a 61-year-old woman who presented to the emergency department in septic shock. She had a 1-week history of increasing back pain before presenting to us. Computed tomography revealed extensive soft tissue emphysema with involvement of the L3 vertebral body and spina canal. She underwent emergency surgical debridement. Despite maximal medical and surgical therapies, the patient died secondary to multisystem organ failure within 36 hours of initial presentation. CONCLUSIONS: To the best of our knowledge, the literature presents only 1 previous case reported involving the spine. Necrotizing fasciitis is an unusual surgical spine surgery emergency. Spine surgeons should be aware of this diagnosis in order to provide timely aggressive surgical debridement.

Pre-education Enhances the Success of Manual Training for Orthopedic Surgery Residents.

INTRODUCTION: Surgical skill training is difficult due to limited resources and the associated risks in the clinical setting. There have been many studies that have looked at optimizing resident skill techniques out of the operating room to optimize intraoperative teaching. Specifically, as seen in spine surgery performing a laminectomy with a high-speed drill is difficult and requires many hours of training and guidance before a resident can feel comfortable to adequately complete the laminectomy with minimal risk of adverse effects. OBJECTIVE: The objective of this study is to assess if pre-education of residents prior to using the high-speed drill will significantly increase their comfort level, as well as increase the success of laminectomy. DESIGN, SETTING AND PARTICIPANTS: This was done by a prospective cohort study in evaluating 20 orthopedic surgical residents via the objective structured assessment of technical skills and global rating scale. RESULTS: Results showed that residents who had pre-education were in fact more successful in completing the laminectomy with the high-speed drill. CONCLUSIONS: Pre-education, whether via a didactic or simulator-based model are both beneficial to resident's knowledge and surgical skill attainment however the simulator based model did not deem the group more successful in completing the laminectomy with the high-speed drill. Certain technical skills still require unreplaceable hands-on practice to become proficient.

Evidence of impaired pain modulation in adolescents with idiopathic scoliosis and chronic back pain.

BACKGROUND CONTEXT: Although 40% of adolescent idiopathic scoliosis (AIS) patients present with chronic back pain, the pathophysiology and underlying pain mechanisms remain poorly understood. We hypothesized that development of chronic pain syndrome in AIS is associated with alterations in pain modulatory mechanisms. PURPOSE: To identify the presence of sensitization in nociceptive pathways and to assess the efficacy of the diffuse noxious inhibitory control in patients with AIS presenting with chronic back pain. STUDY DESIGN: Cross-sectional study. PATIENT SAMPLE: Ninety-four patients diagnosed with AIS and chronic back pain. OUTCOME MEASURES: Quantitative sensory testing (QST) assessed pain modulation and self-reported questionnaires were used to assess pain burden and health-related quality of life. METHODS: Patients underwent a detailed pain assessment using a standard and validated quantitative sensory testing (QST) protocol. The measurements included mechanical detection thresholds (MDT), pain pressure threshold (PPT), heat pain threshold (HPT), heat tolerance threshold (HTT), and a conditioned pain modulation (CPM) paradigm. Altogether, these tests measured changes in regulation of the neurophysiology underlying the nociceptive processes based on the patient's pain perception. Funding was provided by The Louise and Alan Edwards Foundation and The Shriners Hospitals for Children. RESULTS: Efficient pain inhibitory response was observed in 51.1% of patients, while 21.3% and 27.7% had sub-optimal and inefficient CPM, respectively. Temporal summation of pain was observed in 11.7% of patients. Significant correlations were observed between deformity severity and pain pressure thresholds (p=.023) and CPM (p=.017), neuropathic pain scores and pain pressure thresholds (p=.015) and temporal summation of pain (p=.047), and heat temperature threshold and pain intensity (p=.048). CONCLUSIONS: Chronic back pain has an impact in the quality of life of adolescents with idiopathic scoliosis. We demonstrated a high prevalence of impaired pain modulation in this group. The association between deformity severity and somatosensory dysfunction may suggest that spinal deformity can be a trigger for abnormal neuroplastic changes in this population contributing to chronic pain syndrome.

Blood monoamines as potential biomarkers for conditioned pain modulation efficacy: An exploratory study in paediatrics.

BACKGROUND: Monoaminergic pathways are involved in the process of pain inhibition and facilitation. The objective of this study was to investigate the role of blood monoamines as biomarkers of conditioned pain modulation (CPM) efficacy. METHODS: One hundred and five paediatric patients with chronic back pain were enrolled in this observational study. The protocol involved dosage of plasma monoamines (dopamine, DOPA; serotonin, 5-HT; epinephrine, Epi; norepinephrine, NE; metanephrine, ME; and normetanephrine, NME) and clinical assessment (CPM, functional disability, pain, sleep quality, anxiety and depression). RESULTS: 5-HT and DOPA were positively correlated among each other and were both negatively correlated with Epi, ME, NE and NME. CPM presented a positive correlation with DOPA and 5-HT. On the other hand, Epi, ME, NE and NME correlated negatively with CPM. Different correlation coefficients were observed between genders, with stronger coefficients being observed in the male subpopulation. Stepwise regression controlling for age and gender indicated that ME (B = -0.987, SE(B) = 0.299, p = 0.002) was the only significant predictor for CPM efficacy. Higher blood ME was associated with poorer CPM efficacy. ME explained 53% of variation of CPM in males (R2  = 0.536, p < 0.0001) and 7% in females (R2  = 0.074, p = 0.014). In males, blood ME >15 pg/ml predicted inefficient CPM with 88.9% sensitivity and 83.3% specificity. CONCLUSIONS: Our findings suggest that ME can be a potential biomarker for CPM efficacy in paediatrics. Future studies are needed to assess the efficacy of tailored treatments for pain according to blood ME. SIGNIFICANCE: We were able to demonstrate an association between CPM and circulating monoamines. In the clinical setting, sampling ME could provide the clinician an idea of the individual's pain modulation potential. This may be particularly important for children with cognitive impairment, for whose CPM paradigm cannot be used.

Acute postoperative opioid consumption trajectories and long-term outcomes in pediatric patients after spine surgery.

Background: The days following surgery are a critical period where the use of opioids predicts long-term outcomes in adults. It is currently unknown as to whether opioid consumption throughout the acute postoperative period is associated with long-term outcomes in pediatric patients. The aims of this study were to characterize opioid consumption trajectories in the acute postoperative period, identify predictors of trajectory membership and determine associations between opioid consumption trajectories and long-term patient outcomes. Materials and methods: Medication use, pain and mental health status were assessed at baseline in adolescents with idiopathic scoliosis who were scheduled for spinal fusion surgery. Cumulative 6-hr opioid consumption was recorded for up to 5 days after spinal surgery. At 6 months after surgery, medication use, pain and functional activity were evaluated. Growth mixture modeling was used to identify opioid trajectories. Results: One hundred and six patients were included in the study. Mean cumulative 6-hr opioid consumption in the acute postoperative period was 13.23±5.20 mg/kg. The model with the best fit contained 5 acute postoperative trajectories and a quadratic term (AIC =6703.26, BIC =6767.19). Two types of patient behaviors were identified: high opioid consumers (trajectories 4 and 5) and low opioid consumers (trajectories 1, 2 and 3). Intraoperative intrathecal morphine dose was a predictor of trajectory membership (p=0.0498). Opioid consumption during the acute postoperative period was not significantly associated with pain, functional activity or pain medication use at 6 months after surgery. Conclusion: In pediatric patients, intraoperative intrathecal morphine dose predicts opioid consumption in the acute postoperative period. Importantly, opioid consumption during this period does not affect long-term outcomes in pediatric patients after a spine surgery.

Assessing publication rate of abstracts presented in spine conferences as a quality benchmark: the example of the Canadian Spine Society Annual Meetings.

INTRODUCTION: Publication rate can indirectly assess the quality of research presented in scientific meetings. Considering presentations at orthopedic surgery and neurosurgery meetings, 10.5-66% of abstracts are published in scientific journals. Publication rate of abstracts presented at CSS Meetings is unknown. The objective of this study was to evaluate the publication rate of abstracts presented at the Canadian Spine Society(CSS) Annual Meetings from 2005to2014. METHODS: In October2018, a systematic PubMed search was performed using title and authors of all abstracts presented at CSS Meetings from 2005 to 2014. The following information was retrieved from the articles and abstracts: year, type of presentation, publication in PubMed, time from presentation to final publication, journal and its impact factor(IF). RESULTS: A total of 621 abstracts were presented at CSS meetings from 2005 to 2014. Publication rate in PubMed was 54.8%(N=340/621). Oral presentations were more likely to be published than poster presentations(63.8%vs44.0%; OR=1.45; CI95%=1.20-1.75; P<0.0001). The mean time from presentation to publication was 1.76 years(±1.93). The 340 identified articles were published in 87 different journals. Most common journals were Spine(N=75; 22.1%), The Spine Journal(N=40;11.8%), and Journal of Neurosurgery:Spine(N=28;8.2%). IF ranged from 0.18 to 47.66(mean=3.73±4.68). IF of articles presented orally were higher than those presented as poster(P=0.038). CONCLUSIONS: The CSS scientific meeting maintain along the years a steady high quality research presentations as manifested by its significant publication rate(54.8%) in medical journals with mean IF of 3.73. In comparison with other spine scientific meetings, publication rates of abstracts presented at CSS meeting is amongst the highest.