Contribution of MRI and imaging exams in the diagnosis of lumbar pseudarthrosis.

INTRODUCTION: The diagnosis of pseudoarthrosis is based on imaging and clinical exam findings. The standard for pseudarthrosis diagnosis remains postoperative observation through computer tomography (CT) and patient's symptoms. This can be further augmented by dynamic X-ray imaging or nuclear positron emission tomography (PET) CT to demonstrate an absence of fusion by showing a persistence of mobility. However, there is not a uniform diagnostic approach that is a standard of care amongst spine practioners. The aim of this study is to describe the timeline and diagnostic analysis for pseudoarthrosis between the initial surgery and follow-up procedure. METHODS: This is a single-center retrospective observational study. The aim was to enroll patients reoperated for pseudarthrosis after 1 or 2 level lumbar fusions, between August 1st, 2008 and August 1st, 2018. The exams were reviewed by one surgeon and one radiologist, defining a status either in favor of pseudarthrosis, or against it, or inconclusive, based on the radiological criteria mentioned below. We then investigated different combinations of exams and their specific chronology before a diagnosis was established. RESULTS: Forty-four patients were included, 70.5% male and with a mean age of 47.3 years. The median time between the 2 surgeries was 23.7 months. Plain X-rays supported the diagnosis in 38.7% of cases, dynamic X-rays showed hypermobility in 50% of cases. The CT-scan demonstrated pseudarthrosis in 94,4% of cases. A MODIC 1 signal was observed in 87,2% of cases on MRI. SPECT-CT showed a tracer uptake in 70% of cases. CONCLUSION: Reducing the time to reintervention is a key objective for improving the management and clinical outcomes of these patients. We suggest that MRI is an additional tool in combination with CT in the assessment of suspected mechanical pseudarthrosis, in order to optimize the diagnosis and shorten the time to revision surgery. LEVEL OF EVIDENCE: IV.

Manifestación clínica inicial de la lipomatosis epidural lumbar grado III de Naka: serie de casos / Initial clinical signs of Naka's grade III lumbar epidural lipomatosis: A case series

Introducción: La lipomatosis epidural espinal es una enfermedad infrecuente caracterizada por el sobrecrecimiento del tejido adiposo no encapsulado dentro del espacio epidural. Esto genera una estenosis del conducto espinal que puede provocar sintomatología compresiva. La presentación típica es insidiosa a lo largo de meses o años. El objetivo de este estudio fue realizar un análisis descriptivo de la manifestación clínica inicial en pacientes con lipomatosis epidural espinal grado III de Naka. Materiales y métodos: Estudio observacional retrospectivo en la Unidad de Patología Espinal de 4 instituciones, de 2010 a 2023. Se incluyó a pacientes >18 años, de ambos sexos, que acudieron por dolor lumbar con irradiación o sin irradiación, y presentaban lipomatosis lumbar Naka III en la resonancia magnética. Resultados: Se incorporó a 40 pacientes (edad promedio 62.5 años). El 75% era obeso, ninguno era fumador. El motivo de consulta más frecuente fue lumbalgia, con una mediana de evolución del dolor de 5.5 meses. Conclusiones:La lumbalgia fue la consulta más frecuente, con excepción del compromiso de L3-S1 que fue la lumbocruralgia. Los pacientes que sufrieron dolor más tiempo (>6 meses) eran más jóvenes y tenían un índice de masa corporal menor; sin embargo, no resultó estadísticamente significativo. Nivel de Evidencia: IV

Introduction: Spinal epidural lipomatosis (SEL) is a rare pathology characterized by the overgrowth of nonencapsulated adipose tissue within the epidural space. This generates spinal stenosis, which might result in compression symptoms. The typical presentation is insidious pain that lasts months or years. The objective of this study was to carry out a descriptive analysis of the initial clinical signs of patients with Naka's grade III lumbar SEL. materials and methods: Retrospective observational study in the Spinal Pathology Unit of 4 institutions, from 2010 to 2023. Patients over the age of 18, of both sexes, who consulted for low back pain with or without radiation and presented Naka's grade III lumbar lipomatosis on magnetic resonance imaging (MRI) were included. Results: We included 40 patients, with a mean age of 62.5 years; 75% were obese, there were no smokers. The most frequent reason for consultation was low back pain, with a median duration of 5.5 months. Conclusions: The most common reason for consultation was low back pain, with the exception of L3-S1 level involvement, which caused lumbar pain with radiation to the thigh. Patients with a longer period of pain (>6 months) were younger and had a lower BMI; although this was not statistically significant. Level of Evidence: IV

An age and sex matched study on the effect of obesity on the functional outcomes and complication rates in patients with adult spinal deformity undergoing primary multi-level thoracolumbar spinal fusion.

Background: The objective of this study was to determine the effect of obesity on the functional outcomes and complication rates of patients with adult spinal deformity (ASD) undergoing multi-level thoracolumbar fusion. Methods: An age and sex matched comparison of functional outcomes [Numeric Rating Scale (NRS) back and leg scores, Core Outcome Measurement Index (COMI) back scores, Scoliosis Research Society 22 (SRS22) satisfaction and total scores, Short Form 36 (SF36) general health scores, Physical Component Score (PCS), Mental Component Score (MCS), Oswestry Disability Index (ODI) (including all domains)] at 6 months, 1, 2, 3 and 4 years and the complication rates at final follow-up between obese [body mass index (BMI) >30] and normal BMI (18.5-24.9) patients undergoing more than 3 levels of thoracolumbar fusion with a minimum 2-year follow-up. Patients who had undergone any previous spinal surgery were excluded. Results: Thirty patients were included in each arm of the study. Baseline demographics, including the number of levels fused, were similar between the groups. Estimated blood loss (EBL) was higher in obese patients (1,916 vs. 1,099 mL, P=0.001), but operative time was similar (282 vs. 320 min, P=0.351). The functional outcomes and satisfaction scores were consistently poorer in the obese group at all time-points, but their satisfaction scores were similar. Obese patients had a higher complication rate (OR 3.05, P=0.038) predominantly due to dural tears and nerve root injuries, but a similar reoperation rate. Conclusions: In patients with ASD undergoing multi-level thoracolumbar fusion, obesity results in a higher blood loss, poorer sagittal correction, poorer post-operative functional scores and higher complication rates than patients with a normal BMI. However, obesity does not affect operative times, length of hospital stay or reoperation rates. Furthermore, patients with obesity have similar post-operative satisfaction scores to patients with normal BMIs.

Diagnosis of reoperated cervical non-union: Multicenter retrospective study about 45 patients.

INTRODUCTION: Non-union is one of the main complications of single- or multi-level cervical spine fusion, considerably impairing functional results. The aim of this study was to evaluate the respective contributions of imaging examinations in the diagnostic process, the challenge being to avoid inappropriate surgery and unnecessary complementary examinations. MATERIAL AND METHOD: A retrospective multicenter study included all patients managed for cervical spine non-union between 2008 and 2018. We evaluated the imaging examinations performed on each patient and determined signs of non-union in each image. RESULTS: The study included 45 patients in 4 centers: 55% female; mean age, of 48±8.0 years; 57% smokers. Systematic static radiography showed signs of non-union in 55% of cases. Dynamic X-ray was performed in 34% of patients, and showed hypermobility of the level in 80% of cases. CT supported diagnosis of non-union in 97% of cases, and MRI in 48%. SPECT-CT was positive in all cases of non-union. DISCUSSION: Dynamic X-ray is rarely prescribed, but frequently provided an objective measure of hypermobility of the level in non-union, justifying first-line use. Millimetric-slice CT was reliable for diagnosis. MRI is relevant only once diagnosis has been made, as part of preoperative work-up. Nuclear imaging can be useful in order to solve doubtful cases. CONCLUSION: In suspected cervical spine non-union, we recommend dynamic X-rays (flexion/extension) and CT-scan as first-line diagnosis examinations. LEVEL OF EVIDENCE: IV.

Static and dynamic sagittal lumbar apex: a new concept for the assessment of lumbar lordosis distribution in spinal deformity.

PURPOSE: Sagittal lumbar apex has been demonstrated to be a key parameter in sagittal plane morphology. Our aim was to understand its behavior with postural changes, analyzing two different concepts of lumbar apex. MATERIALS AND METHODS: Prospective observational study with a cohort of patients presenting sagittal malalignment identified from a monocenter database of adult spinal deformities (ASD). Inclusion criteria were age > 30 years, SVA > 40 mm, and/or PT > 20. All patients had full-spine EOS radiographs in 2 different positions: (P1: natural position) and position 2 (P2: compensated position). Sagittal alignment, spinopelvic values, and two different methods of assessing lordosis apex location were analyzed in both P1 and P2 positions. Changes between P1 and P2 were compared using a paired t test with a significance level at p < 0.05. RESULTS: Twenty-five patients were recruited (21 women and 4 men). The mean age was 64.8 years (range 21-79). The patient's main compensation was based on an increase in the femoral shaft angle, and pelvic retroversion, with a subsequent decrease in sacral slope, and therefore of the lower lumbar arc. When the lumbar apex was calculated as the most anterior point touching the vertical line in a lateral radiograph, postural compensation changes modified its location usually shifting it to a more caudal position. When the lumbar apex was assessed as the most distant point of the global lumbar lordosis, its position remained stable regardless of compensation. CONCLUSIONS: Postural changes can modify the location of the lumbar apex when understanding its location as the cornerstone of sagittal plane harmonic distribution. This concept can be useful as an additional sign to assess compensation. However, if the lumbar apex was calculated as the angular point of the global lordosis, its position remained stable regardless of postural changes. This concept can help to mold lumbar lordosis in ASD surgery. LEVEL OF EVIDENCE IV: Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.

An Anterior Dislocation after Mobi-C Cervical Disc Arthroplasty.

The objective is to report a case of an early dislocation of Mobi-C prosthesis used for the replacement of C4-C5 disc. A 57-year-old man who was operated 17 years before for C6-C7 fusion complained of cervicalgia associated with bilateral but predominantly right-sided brachialgia. Magnetic resonance imaging demonstrated central and foraminal stenosis in the C5-C6 segment and soft medial disc herniation in the C4-C5 segment. The patient was indicated for the placement of a cervical disc prosthesis C4-C5 and a C5-C6 arthrodesis. After 1 month of clinical improvement, the patient saw his pain reappearing as well as the presence of dysphagia not objectified before. The patient did not describe a traumatic context. The radiographic assessment showed an anterior dislocation of the prosthesis. The patient was reoperated, the prosthesis was removed, and cervical arthrodesis with iliac graft was performed. Although rare, this complication must be well known by surgeons performing cervical arthroplasty.

Prediction of satisfaction after correction surgery for adult spinal deformity: differences between younger and older patients.

PURPOSE: Achieving an adequate level of patient's satisfaction with results is one of the goals of adult spinal deformity (ASD) surgery. However, it is unclear whether the same factors affect satisfaction in all patient populations. Patients' age influences the postoperative course and prevalence of complications after ASD surgery. The purpose of this study was to determine the factors predicting satisfaction 2 years after ASD surgery in younger and older patients. METHODS: A total of 119 patients under 40 years old, 155 patients 40 to 65 years old, and 148 patients over 65 years old at surgery who were followed for a minimum of 2 years after surgery were included. Multivariate analysis was used to determine independent related factors with maximum AUC for satisfaction 2 years after surgery in each group. A propensity-matched cohort under equivalent demographic and clinical characteristics was used to confirm the results. RESULTS: Logistic regression analyses revealed satisfaction among the under-40 group corresponded to prior spine surgery, complications, and self-image. That among the 40-to-65 group corresponded to neurologic complication, revision surgery, pain, and sagittal vertical axis restoration. Among the over-65 group satisfaction correlated with revision surgery, standing ability, and lumbar lordosis index restoration. Propensity score matching confirmed that sagittal alignment correction led to substantial satisfaction. CONCLUSIONS: In younger patients, avoiding complications and improving patients' self-image were essential for substantial satisfaction levels. In older patients, revision, standing ability, as well as sagittal spinopelvic alignment restoration, were the key factors. Surgeons should consider the differences in goals of each patient.

Sacral hiatus corticosteroid injection in the management of radicular pain in adults.

Radicular pain is a common reason for patients to consult at back pain clinics. While epidural steroid injections are widely done, some aspects are still controversial. The epidural space can be accessed via a transforaminal approach, an interlaminar route or by passing through the sacral hiatus. The aim of this article is to describe the epidural injection technique through the sacral hiatus that our team uses and to report our experience with it. Beyond the treatment effect, sacral hiatus corticosteroid injection can be useful as a diagnostic test or as an interim solution. Image-guided injection is recommended to ensure optimal positioning of the needle below S3. Sacral hiatus corticosteroid injection is a relevant alternative for treating lumbar radiculopathy in adults.

Clinical Performance and Concurrent Validity of the Adult Spinal Deformity Surgical Decision-making Score.

STUDY DESIGN: Multicenter, retrospective study. OBJECTIVE: The aim of this study was to examine the performance and concurrent validity of the adult spinal deformity surgical decision-making (ASD-SDM) score compared to decision-making factors in the ASD population. SUMMARY OF BACKGROUND DATA: The ASD-SDM score, which has been recently proposed, is a scoring system to guide the selection of treatment modality for the ASD population. To secure the justification for its clinical use, it is necessary to verify its clinical performance and concurrent validity. METHODS: A multicenter prospective ASD database was retrospectively reviewed. The data were analyzed separately in younger (≤40 years) and older (≥41 years) age groups. The discriminating capacity of the ASD-SDM score in cases who selected surgical and nonsurgical management was compared using area under the receiver operator characteristic curves (AUROC). Concurrent validity was examined using Spearman correlation coefficients, comparing factors that are reported to be associated with the decision-making process for ASD, including baseline symptomatology, health-related quality of life measures, and the severity of radiographic spinal deformity. RESULTS: There were 338 patients (mean age: 26.6 years; 80.8% female; 129 surgical and 209 nonsurgical) in the younger age group and 750 patients (mean age: 63.5 years; 84.3% female; 410 surgical and 340 nonsurgical) in the older age group. In both younger and older patients, the ASD-SDM score showed a significantly higher performance for discriminating the surgical and nonsurgical cases (AUROC: 0.767, standard error [SE]: 0.026, P < 0.001, 95% confidence interval [CI]: 0.712-0.813; AUROC: 0.781, SE: 0.017, P < 0.001, 95% CI: 0.747-0.812, respectively) compared to the decision-making factors analyzed. In addition, the ASD-SDM showed significant correlations with multiple decision-making factors. CONCLUSION: The ASD-SDM score alone can effectively grade the indication for surgical management whilst considering multiple decision-making factors. LEVEL OF EVIDENCE: 3.

Idiopathic Epidural Lipomatosis Associated with Degenerative Discopathy: Grand Round Presentation of Unusual Lumbar Canal Stenosis Resolved by Weight Loss.

Here, we report a case of idiopathic epidural lipomatosis presented with a clinical picture of lumbar canal stenosis with neurogenic claudication which resolved completely only by weight loss. A 53-year-old obese male with a body mass index of 36 without significant past medical history presented to the outpatient clinic with neurogenic claudication and bilateral sciatic radiculopathy. Initially, magnetic resonance imaging (MRI) showed epidural lipomatosis at the level of L5 vertebral body and L5-S1 intervertebral disc. A conservative treatment was decided with dietary regime program. After 6 months of follow-up, his bilateral sciatic radiculopathy disappeared, and updated MRI showed complete disappearance of epidural lipomatosis. Based on the Grand Round case and relevant literature, we present a case of an unusual epidural lipomatosis with mixed clinical picture of degenerative lumbar disease. This case report set out the importance of Borré classification for differentiating the mixed clinical complaint of degenerative discopathy and epidural lipomatosis.

Multiple-rod constructs in adult spinal deformity surgery for pelvic-fixated long instrumentations: an integral matched cohort analysis.

PURPOSE: Multiple-rod constructs (Multi-Rod: extra rods for additional pillar support) are occasionally used in adult spinal deformity (ASD) surgery. We aimed to compare and analyze the general outcome of multi-rod constructs with a matched two-rod cohort, to better understand the differences and the similitudes. METHODS: This is a retrospective matched cohort study including patients with ASD that underwent surgical correction with long posterior instrumentation (more than five levels), pelvic fixation and a minimum 1-year follow-up. Matching was considered with demographical data, preoperative radiographical parameters, preoperative clinical status [health-related quality-of-life (HRQoL) scores] and surgical characteristics (anterior fusion, decompression, rod material, osteotomies). Postoperative radiographical and clinical parameters, as well as complications, were obtained. Univariate and multivariate analysis was performed regarding postoperative improvement, group variables comparison and parameters correlation. RESULTS: Thirty-three patients with multi-rod construct and 33 matched with a two-rod construct were selected from a database with 346 ASD-operated patients. Both groups had a significant improvement with surgical management in the radiographical and HRQoL parameters (p < 0.001). Differences between groups for the postoperative radiographical, clinical and perioperative parameters were not significant. Rod breakage was more frequent in the two-rod group (8 vs 4, p = 0.089), as well as the respective revision surgery for those cases (6 vs 1 p = 0.046). Risk factors related to revision surgery were greater kyphosis correction (p = 0.001), longer instrumentation (p = 0.037) and greater sagittal vertical axis correction (p = 0.049). CONCLUSION: No major disadvantage on the use of multi-rod construct was identified. This supports the benefit of using multi-rod constructs to avoid implant failure. These slides can be retrieved under Electronic Supplementary Material.

Opioids and analgesics use after adult spinal deformity surgery correlates with sagittal alignment and preoperative analgesic pattern.

PURPOSE: To assess pain, health-related quality of life (HRQOL) scores and sagittal parameters of adult spinal deformity (ASD)-operated patients in the context of their analgesic consumption especially opioids (narcotics) over the first year postoperative period. METHODS: In total, 372 patients from a multicenter database were stratified into 3 groups at baseline: 241 patients in the minimal group (no analgesic, or NSAIDs/narcotics weekly or less), 64 in the NSAIDs every day group and 67 in the narcotics every day group. HRQOL and back and leg pain scores were evaluated at 6 months and 1 year postoperatively. Also several sagittal alignment parameters were assessed. RESULTS: Significant improvements in pain and HRQOL scores were observed across all 3 groups by 1 year (P < 0.05) postoperatively. While the minimal group had the best pre- and postoperative HRQOL scores, the NSAID group demonstrated the best improvement in HRQOL. Only the minimal group displayed continued improvement from 6 months to 1 year. 90%, 65% and 40% of minimal, NSAID and narcotic groups of patients, respectively, no longer took any analgesics at 1 year postoperatively. Alternatively, 36% of patients in the narcotics group continued to take narcotics at 1 year. Residual malalignment increased NSAIDs consumption in different groups at 1 year. CONCLUSION: This study evaluated the analgesics use after ASD surgery in relation to the clinical and radiological outcomes. Despite important postoperative opioids consumption in the narcotics group, clinical outcome yet improved. Malalignment parameters demonstrated a predictive value in regard to NSAIDs' usage. These slides can be retrieved under Electronic Supplementary Material.

Adult spinal deformity surgical decision-making score. Part 2: development and validation of a scoring system to guide the selection of treatment modalities for patients above 40 years with adult spinal deformity.

PURPOSE: We aimed to develop and internally validate a scoring system, the adult spinal deformity surgical decision-making (ASD-SDM) score, to guide the decision-making process for ASD patients aged above 40 years. METHODS: A multicentre prospective ASD database was retrospectively reviewed. The scoring system was developed using data from a derivation set and was internally validated in a validation set. The performance of the ASD-SDM score for predicting surgical management was assessed using the area under the receiver operating characteristic curve (AUC). RESULTS: A total of 702 patients were included for analysis in the present study. The scoring system developed based on 562 patients, ranging from 0 to 12 points, included five parameters: leg pain scored by the numerical rating scale; pain and self-image domains in the Scoliosis Research Society-22 score; coronal Cobb angle; and relative spinopelvic alignment. Surgical indication was graded as low (score 0 to 4), moderate (score 5 to 7), and high (score 8 to 12) groups. In the validation set of 140 patients, the AUC for predicting surgical management according to the ASD-SDM score was 0.797 (standard error = 0.037, P < 0.001, 95% confidence interval = 0.714 to 0.861), and in the low, moderate, and high surgical indication groups, 23.7%, 43.5%, and 80.4% of the patients, respectively, were treated surgically. CONCLUSIONS: The ASD-SDM score demonstrated reliability, with higher scores indicating a higher probability of surgery. This index could aid in the selection of surgery for ASD patients in clinical settings. These slides can be retrieved under Electronic Supplementary Material.

Mental health status and sagittal spinopelvic alignment correlate with self-image in patients with adult spinal deformity before and after corrective surgery.

PURPOSE: Preoperative patient self-image (SI) in adult spinal deformity (ASD) is the most relevant factor for surgical decision-making. Postoperative SI has an important role in a patient's satisfaction with surgery. However, few studies are available to describe these variables. The aim was to investigate the factors that correlate with SI before and 2 years after ASD surgery. METHODS: This study was a retrospective review of prospectively collected multicentric data. Patients who underwent ASD surgery with a minimum follow-up of 2 years were enrolled (n = 391). They were divided into high-SI and low-SI groups, both preoperatively and postoperatively, according to SRS-22R SI/appearance subdomain scores at baseline and at 2 years, respectively. Independently related factors for SI were determined using logistic regression analysis. RESULTS: Crucial factors for SI at baseline were the scores on the SRS-22R function/activity (OR: 2.61), SRS-22R mental health (OR: 2.63) subdomains, and relative spinopelvic alignment (RSA, OR: 0.95). SF-36 MCS (OR: 1.07) at baseline as well as sagittal vertical axis (SVA, OR: 0.99) at 2 years, and complications (OR: 0.44) were independent predictive factors for SI at 2 years. The patients who transitioned from the preoperative low-SI group to the postoperative high-SI group achieved larger global sagittal alignment restoration and had lesser complications than those who did not. CONCLUSIONS: Mental status and sagittal spinopelvic alignment are key determinants of SI. The results indicate that considering mental status, preventing complications, and global sagittal alignment, restoration is crucial for achieving substantial SI scores after ASD surgery. These slides can be retrieved under Electronic Supplementary Material.

Carbon-fibre cage reconstruction in anterior cervical corpectomy for multilevel cervical spondylosis: mid-term outcomes.

BACKGROUND: Mid-term clinical and radiological evaluation of a carbon-fiber cage in multilevel cervical spondylosis (MCS). Anterior cervical corpectomy and fusion (ACCF) using titanium mesh cages (TMC) has shown satisfactory outcomes, but with subsidence of up to 20%. Conventional long-fiber carbon fiber cages have shown a safe profile in discectomy/fusion (ACDF) but with minimal data in the setting of corpectomy. METHODS: Retrospective review of a single centre multi-surgeon cohort of MCS patients from 2007-2012. Follow-up period was a minimum of 3.5 years, mean 6 years. Outcomes included peri-operative, clinical [Nurick, European Myelopathy, Visual Analogue Scores (VAS), modified Japanese Orthopaedic Association (mJOA) scores and radiographic (C2C7, Cobb & ROM angles)]. RESULTS: A total of 102 consecutive patients were included. Mean length of stay was 5.5 (SD 3.5) days, blood loss 322 (SD 358) mL and operative time 98 (SD 31) min. Corpectomy levels included 72 single-level ACCF and 30 multiple ACCF. Fourteen had peri-operative complications. Three patients required early cage revisions. Mean pain scores improved from VAS neck 4.6 to 2.6 (P<0.01) and VAS arm 5.1 to 2.0 (P<0.01). Mean Nurick score improved from 1.2 to 0.4/4 (P<0.01). Mean follow-up EMS was 15.9/18 and mJOA was 14.0/17. Seventy follow-up radiographs were obtained. Flexion-extension angulation differences of >3 mm across the instrumented level were present in 5 patients, all of which displayed fusion of either grade 1 or 2. 7 had C2C7 kyphosis. Severe subsidence (>3 mm) was seen in 9 cases (13%). CONCLUSIONS: Mid-term outcomes of this carbon-fiber cage indicate that it is safe and durable for the treatment of MCS with a similar radiological profile to that of TMC.

Factors influencing patient satisfaction after adult scoliosis and spinal deformity surgery.

OBJECTIVE: Achieving high patient satisfaction with management is often one of the goals after adult spinal deformity (ASD) surgery. However, literature on associated factors and their correlations with patient satisfaction is limited. The aim of this study was to determine the clinical and radiographic factors independently correlated with patient satisfaction in terms of management at 2 years after surgery. METHODS: A multicenter prospective database of ASD surgery was retrospectively reviewed. The demographics, complications, health-related quality of life (HRQOL) subdomains, and radiographic parameters were examined to determine their correlation coefficients with the Scoliosis Research Society-22 questionnaire (SRS-22R) satisfaction scores at 2 years (Sat-2y score). Subsequently, factors determined to be independently associated with low satisfaction (Sat-2y score ≤ 4.0) were used to construct 2 types of multivariate models: one with 2-year data and the other with improvement (score at 2 years - score at baseline) data. RESULTS: A total of 422 patients who underwent ASD surgery (mean age 53.1 years) were enrolled. All HRQOL subdomains and several coronal and sagittal radiographic parameters had significantly improved 2 years after surgery. The Sat-2y score was strongly correlated with the SRS-22R self-image (SI)/appearance subdomain (r = 0.64), followed by moderate correlation with subdomains related to standing (r = 0.53), body pain (r = 0.49-0.55), and function (r = 0.41-0.55) at 2 years. Conversely, the correlation between radiographic or demographic parameters with Sat-2y score was weak (r < 0.4). Multivariate analysis to eliminate confounding factors revealed that a worse Oswestry Disability Index (ODI) score for standing (≥ 2 points; OR 4.48) and pain intensity (≥ 2 points; OR 2.07), SRS-22R SI/appearance subdomain (< 3 points; OR 2.70) at 2 years, and a greater sagittal vertical axis (SVA) (> 5 cm; OR 2.68) at 2 years were independent related factors for low satisfaction. According to the other model, a lower improvement in ODI for standing (< 30%; OR 2.68), SRS-22R pain (< 50%; OR 3.25) and SI/appearance (< 50%; OR 2.18) subdomains, and an inadequate restoration of the SVA from baseline (< 2 cm; OR 3.16) were associated with low satisfaction. CONCLUSIONS: Self-image, pain, standing difficulty, and sagittal alignment restoration may be useful goals in improving patient satisfaction with management at 2 years after ASD surgery. Surgeons and other medical providers have to take care of these factors to prevent low satisfaction.

Sacroiliac joint morphologic changes from infancy to adulthood.

BACKGROUND CONTEXT: Report of sacroiliac morphology changes during growth is limited in the literature and the interest of such morphology and its consequence for surgery is increasing. PURPOSE: Aims of this work are (1) to anatomically define the sacroiliac joint (SIJ), and (2) to assess the influence of growth on the sacroiliac morphology and the pelvic parameters. STUDY DESIGN: Forty-nine young subjects from 6 months to 18 years old (y/o) and 20 adults aged from 18 to 50 y/o were selected from our institutional patient database. METHODS: They underwent a computed tomography (CT) examination on a 128-MDCT (GE Healthcare Optima CT660). Transverse CT image datasets were reconstructed, anonymized, and segmented with ITK-SNAP. Landmarks and surfaces were selected and a SIJ orientation analysis was performed using costumed Python scripts. RESULTS: The subjects were divided into four groups: infants (1.9±1 y/o), children (6.9±1.7 y/o), adolescents (13.7±1.8 y/o), and adults (27.3±5.6 y/o). Differences between SIJ orientation were found significant between young subject groups for synovial sacrum SIJ orientation (p<.001) and iliac total SIJ orientation (p=.036). Both orientations of younger subjects were found significantly different from the adult group (p<.035). SIJ synovial sacrum and iliac total orientations correlated significantly with age (p<.03). All orientations correlated with pelvic incidence (p<.04) except for synovial sacrum SIJ orientation (p=.2). No gender or symmetrical differences were found significant in any group. CONCLUSIONS: Morphologic definition of the SIJ confirmed the independency of the gender during growth. Such results will be beneficial for the analysis and management of vertebral pathology.

Adult spinal deformity surgical decision-making score : Part 1: development and validation of a scoring system to guide the selection of treatment modalities for patients below 40 years with adult spinal deformity.

PURPOSE: We aimed to develop and internally validate a simple scoring system: the adult spinal deformity (ASD) surgical decision-making (ASD-SDM) score, which is specific to the decision-making process for ASD patients aged below 40 years. METHODS: A multicentre prospective ASD database was retrospectively reviewed. The scoring system was developed using data from a derivation cohort and was internally validated in a validation cohort. The accuracy of the ASD-SDM score was assessed using the area under the receiver operating characteristic curve (AUC). RESULTS: A total of 316 patients were randomly divided into derivation (253 patients, 80%) and validation (63 patients, 20%) cohorts. A 10-point scoring system was created from four variables: self-image score in the Scoliosis Research Society-22 score, coronal Cobb angle, pelvic incidence minus lumbar lordosis mismatch, and relative spinopelvic alignment, and the surgical indication was graded into low (score 0-4), moderate (score 5-7), and high (score 8-10) surgical indication groups. In the validation cohort, the AUC for selecting surgical management according to the ASD-SDM score was 0.789 (SE 0.057, P < 0.001, 95% CI 0.655-0.880). The percentage of patients treated surgically were 21.1%, 55.0%, and 80.0% in the low, moderate, and high surgical indication groups, respectively. CONCLUSIONS: The ASD-SDM score, to the best of our knowledge, is the first algorithm to guide the decision-making process for the ASD population and could be one of the indices for aiding the selection of treatment for ASD. These slides can be retrieved under Electronic Supplementary Material.

Added value of [18F]fluorodeoxyglucose positron emission tomography/computed tomography for the diagnosis of post-operative instrumented spine infection.

PURPOSE: Post-operative instrumented spine infection (PISI) is an infrequent complication. Diagnosis of spinal implant infection can be difficult, especially in case of chronic infection. METHODS: This retrospective study attempts to evaluate the diagnostic performance of [18F]fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) in PISI. Imagings were performed between April 2010 and June 2018 among patients referred for suspected chronic spinal implant infection. PET/CT were performed more than 12 weeks after surgery. PET/CT images were re-interpreted independently by two nuclear medicine physicians without knowledge of the patient's conditions. PET/CT data were analyzed both visually and semi-quantitatively (SUVmax). MRI results were collected from medical records. The final diagnosis of infection was based on bacteriological cultures or a twelve-month follow-up. RESULTS: Forty-nine PET/CT were performed in 44 patients (22 women, median age 65.0 years). Twenty-two patients had a diagnosis of infection during follow-up. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for PET/CT were 86.4%, 81.5%, 79.2%, and 88.0%. Sensitivity, specificity, PPV and NPV were 66.7%, 75.0%, 66.0%, 75.0% respectively for MRI and 50.0%, 92.6%, 84.6% and 69.4% for serum C-reactive protein (CRP). Although these values were higher for PET/CT than for MRI or CRP, the differences were not statistically significant. In this setting, false positives with PET/CT can be observed in case of previous spine infection or adjacent segments disc disease. False negatives can result of extensive instrumented arthrodesis or infection with low virulence bacteria. CONCLUSION: PET/CT is useful for the diagnosis of PISI. These results should be evaluated in further prospective study.