The influence of peri-operative depressive symptoms on medium-term spine surgery outcome: a prospective study.

PURPOSE: To investigate the role of depressive symptoms on clinical outcomes in patients undergoing spinal surgery up to 2-year follow-up. METHODS: The study used data from an institutional spine surgery registry (January 2016, through March 2022) to identify patients (> 18 years) undergoing spine surgery. Patients with Oswestry Disability Index (ODI) < 20/100 at baseline or undergoing surgery on the cervical spine or for idiopathic spinal deformity and trauma patients were excluded. The patients were divided into two groups based on the pre-operative Mental Component Summary (MCS) score of the SF-36: depression group (MCS ≤ 35) or non-depression group (MCS > 35). The ODI and MCS scores trajectory were wined over the 24-month post-surgery between groups. Additionally, a secondary subgroup analysis was conducted comparing outcomes between those with depressive symptoms (persistent-depression subgroup) and those without depressive symptoms (never-depression subgroup) at 3 months after surgery. RESULTS: A total of 2164 patients who underwent spine surgery were included. The pre-operative depression group reported higher ODI total scores and lower MCS than the pre-operative non-depression group at all time points (P < 0.001). The persistent-depression subgroup reported higher ODI total scores and lower MCS than the never-depression subgroup at all follow-ups (P < 0.001). CONCLUSION: Functional disability and mental health status improve in patients with depression symptoms undergoing spinal surgery. Despite this improvement, they do not reach the values of non-depressed subjects. Over the 2-year follow-up time, patients with depression show a different trajectory of ODI and MCS. Caregivers should be aware of these results to counsel patients with depression symptoms.

Automatic classification of the vertebral endplate lesions in magnetic resonance imaging by deep learning model.

Introduction: A novel classification scheme for endplate lesions, based on T2-weighted images from magnetic resonance imaging (MRI) scan, has been recently introduced and validated. The scheme categorizes intervertebral spaces as "normal," "wavy/irregular," "notched," and "Schmorl's node." These lesions have been associated with spinal pathologies, including disc degeneration and low back pain. The exploitation of an automatic tool for the detection of the lesions would facilitate clinical practice by reducing the workload and the diagnosis time. The present work exploits a deep learning application based on convolutional neural networks to automatically classify the type of lesion. Methods: T2-weighted MRI scans of the sagittal lumbosacral spine of consecutive patients were retrospectively collected. The middle slice of each scan was manually processed to identify the intervertebral spaces from L1L2 to L5S1, and the corresponding lesion type was labeled. A total of 1,559 gradable discs were obtained, with the following types of distribution: "normal" (567 discs), "wavy/irregular" (485), "notched" (362), and "Schmorl's node" (145). The dataset was divided randomly into a training set and a validation set while preserving the original distribution of lesion types in each set. A pretrained network for image classification was utilized, and fine-tuning was performed using the training set. The retrained net was then applied to the validation set to evaluate the overall accuracy and accuracy for each specific lesion type. Results: The overall rate of accuracy was found equal to 88%. The accuracy for the specific lesion type was found as follows: 91% (normal), 82% (wavy/irregular), 93% (notched), and 83% (Schmorl's node). Discussion: The results indicate that the deep learning approach achieved high accuracy for both overall classification and individual lesion types. In clinical applications, this implementation could be employed as part of an automatic detection tool for pathological conditions characterized by the presence of endplate lesions, such as spinal osteochondrosis.

Stability and Instrumentation Stresses Among Sacropelvic Fixation Techniques With Novel Porous Fusion/Fixation Implants: A Finite Element Study.

BACKGROUND: Sacropelvic fixation is frequently combined with thoracolumbar instrumentation for correcting spinal deformities. This study aimed to characterize sacropelvic fixation techniques using novel porous fusion/fixation implants (PFFI). METHODS: Three T10-pelvis finite element models were created: (1) pedicle screws and rods in T10-S1, PFFI bilaterally in S2 alar-iliac (S2AI) trajectory; (2) fixation in T10-S1, PFFI bilaterally in S2AI trajectory, triangular implants bilaterally above the PFFI in a sacro-alar-iliac trajectory (PFFI-IFSAI); and (3) fixation in T10-S1, PFFI bilaterally in S2AI trajectory, PFFI in sacro-alar-iliac trajectory stacked cephalad to those in S2AI position (2-PFFI). Models were loaded with pure moments of 7.5 Nm in flexion-extension, lateral bending, and axial rotation. Outputs were compared against 2 baseline models: (1) pedicle screws and rods in T10-S1 (PED), and (2) pedicle screws and rods in T10-S1, and S2AI screws. RESULTS: PFFI and S2AI resulted in similar L5-S1 motion; adding another PFFI per side (2-PFFI) further reduced this motion. Sacroiliac joint (SIJ) motion was also similar between PFFI and S2AI; PFFI-IFSAI and 2-PFFI demonstrated a further reduction in SIJ motion. Additionally, PFFI reduced max stresses on S1 pedicle screws and on implants in the S2AI position. CONCLUSION: The study shows that supplementing a long construct with PFFI increases the stability of the L5-S1 and SIJ and reduces stresses on the S1 pedicle screws and implants in the S2AI position. CLINICAL RELEVANCE: The findings suggest a reduced risk of pseudarthrosis at L5-S1 and screw breakage. Clinical studies may be performed to demonstrate applicability to patient outcomes. LEVEL OF EVIDENCE: Not applicable (basic science study).

The burden of preoperative fear-avoidance beliefs in workers after thoracic and lumbar spine surgery: a 2-year follow-up study.

ABSTRACT: Spinal disorders are the main reasons for sick leave and early retirement among the working population in industrialized countries. When "red flags" are present, spine surgery is the treatment of choice. However, the role of psychosocial factors such as fear-avoidance beliefs in spine surgery outcomes is still debated. The study aims to investigate whether patients presenting high or low levels of fear-avoidance thoughts before the spine surgery reported different surgical results and return-to-work rates over 2 years. From an institutional spine surgery registry, workers surgically treated with a preoperative score in the Oswestry Disability Index (ODI) higher than 20/100 and provided ODI questionnaires, return-to-work status at 3-, 6-, 12-, and 24-month follow-ups were analyzed. A total of 1769 patients were stratified according to the work subscale of the Fear-Avoidance Beliefs Questionnaire (FABQ-W) in high fear (FABQ-W ≥ 34/42) or low fear (FABQ-W < 34/42). Multivariate regression was used to search for preoperative factors, which might interact with FABQ-W. The higher-fear group showed a different recovery pattern, with higher levels of disability according to the ODI (total score, absolute change, frequency of clinically relevant change, and disability categories) and lower return-to-work ratios over the 24-month follow-up. High fear, high disability, greater age, female gender, smoking, and worse physical status at baseline were associated with worse ODI outcomes 2 years after the surgery. In summary, fear-avoidance beliefs significantly influence the speed and the entity of surgical outcomes in the working population. However, the contribution of FABQ-W in predicting long-term disability levels was limited.

Accuracy of Rod Contouring to Desired Angles With and Without a Template: Implications for Achieving Desired Spinal Alignment and Outcomes.

STUDY DESIGN: Biomechanical Study. OBJECTIVE: The search for optimal spinal alignment has led to the development of sophisticated formulas and software for preoperative planning. However, preoperative plans are not always appropriately executed since rod contouring during surgery is often subjective and estimated by the surgeon. We aimed to assess whether rods contoured to specific angles with a French rod bender using a template guide will be more accurate than rods contoured without a template. METHODS: Ten experienced spine surgeons were requested to contour two 125 × 5.5 mm Ti64 rods to 40°, 60° and 80° without templates and then 2 more rods using 2D metallic templates with the same angles. Rod angles were then measured for accuracy and compared. RESULTS: Average angles for rods bent without a template to 40°, 60° and 80° were 60.2°, 78.9° and 97.5°, respectively. Without a template, rods were overbent by a mean of 18.9°. When using templates of 40°, 60° and 80°, mean bend angles were 41.5°, 59.1° and 78.7°, respectively, with an average underbend of 0.2°. Differences between the template and non-template groups for each target angle were all significant (p < 0.001). CONCLUSIONS: Without the template, surgeons tend to overbend rods compared to the desired angle, while surgeons improved markedly with a template guide. This tendency to overbend could have significant impact on patient outcomes and risk of proximal junctional failure and warrants further research to better enable surgeons to more accurately execute preoperative alignment plans.

Effect of Sacropelvic Hardware on Axis and Center of Rotation of the Sacroiliac Joint: A Finite Element Study.

BACKGROUND: The sacroiliac joint (SIJ) transfers the load of the upper body to the lower extremities while allowing a variable physiological movement among individuals. The axis of rotation (AoR) and center of rotation (CoR) of the SIJ can be evaluated to analyze the stability of the SIJ, including when the sacrum is fixed. The purpose of this study was to determine how load intensity affects the SIJ for the intact model and to characterize how sacropelvic fixation performed with different techniques affects this joint. METHODS: Five T10-pelvis models were used: (1) intact model; (2) pedicle screws and rods in T10-S1; (3)pedicle screws and rods in T10-S1, and bilateral S2 alar-iliac screws (S2AI); (4) pedicle screws and rods in T10-S1, bilateral S2AI screws, and triangular implants inserted bilaterally in a sacral alar-iliac trajectory ; and (5) pedicle screws and rods in T10-S1, bilateral S2AI screws, and 2 bilateral triangular implants inserted in a lateral trajectory. Outputs of these models under flexion-extension were compared: AoR and CoR of the SIJ at incremental steps from 0 to 7.5 Nm for the intact model and AoR and CoR of the SIJ for the instrumented models at 7.5 Nm. RESULTS: The intact model was validated against an in vivo study by comparing range of motion and displacement of the sacrum. Increasing the load intensity for the intact model led to an increase of the rotation of the sacrum but did not change the CoR. Comparison among the instrumented models showed that sacropelvic fixation techniques reduced the rotation of the sacrum and stabilized the SIJ, in particular with triangular implants. CONCLUSION: The study outcomes suggest that increasing load intensity increases the rotation of the sacrum but does not influence the CoR, and use of sacropelvic fixation increases the stability of the SIJ, especially when triangular implants are employed. CLINICAL RELEVANCE: The choice of the instrumentation strategy for sacropelvic fixation affects the stability of the construct in terms of both range of motion and axes of rotation, with direct consequences on the risk of failure and mobilization. Clinical studies should be performed to confirm these biomechanical findings.

Is posteromedial translation with sublaminar bands effective in correcting axial rotation in adolescent idiopathic scoliosis surgery? A 3D reconstruction study.

PURPOSE: Hybrid constructs with sublaminar bands have recently regained popularity as an alternative to all-screw construct for correction of adolescent idiopathic scoliosis (AIS). The aim of this study is to evaluate the ability of hybrid constructs with sublaminar bands to achieve a tridimensional correction of the scoliotic deformity. Our hypothesis is that hybrid construct with sublaminar bands are able to achieve a substantial derotation of the apical vertebrae, while preserving the thoracic kyphosis. METHODS: A prospective evaluation of 50 consecutive cases (41 F, 9 M, mean age 14.7 ± 2 years) of AIS correction with hybrid construct was performed. In all cases, sublaminar bands were used at the apex of the main curve on concave side. All patients underwent pre and postoperative X-rays with EOS System, with full 3D reconstruction. Spinopelvic parameters and axial rotation of the vertebrae were measured pre and postoperatively. RESULTS: 2.7 ± 0.9 mean sublaminar bands were used per patient. Mean correction of deformity was 50 ± 9.5%. on the coronal plane. The mean axial rotation of the apical vertebra went from 18° ± 11.5° preoperatively to 9.4° ± 7.2° postoperatively (p < 0.001) with a mean derotation of 47.7%. Thoracic kyphosis went from 32.1° ± 18° preoperatively to 37.3° ± 13.1° postoperatively (p < 0.05). No intraoperative complications due to sublaminar bands were recorded. CONCLUSIONS: Hybrid construct with sublaminar band have been showed to be safe and effective in deformity correction and in maintaining or restoring thoracic kyphosis. This study showed that with sublaminar bands applied at the curve apex a substantial derotation of the apical vertebrae can be achieved.

Perioperative adverse events in adult and pediatric spine surgery: A prospective cohort analysis of 364 consecutive patients.

Introduction: A precise knowledge of the possible Adverse Events (AEs) related to spinal surgical procedures is crucial in clinical practice. Research Question: Purposes of this study are: to determine the prevalence and severity of perioperative AEs associated with pediatric and adult spine surgery in a high volume center; to estimate the impact of perioperative AEs on length of hospital stay (LOS). Material and Methods: This is a prospective, observational, monocenter study, including 346 consecutive patients (294 adults and 52 pediatrics). The SAVES-V2 questionnaire was used to record AEs. The form was updated by the medical staff every time an adverse event was recorded during hospitalization. Results: 21,2% of pediatric patients and 20,7% of adults had at least 1 perioperative AEs. In adults, dural tear (3.1%) and neuropathic pain (4,8%), were the most frequent intraoperative and postoperative AE, respectively. In pediatric patients, neurologic deterioration was the most frequent postoperative AE. A diagnosis of deformity (p=0.01), an ASA grade equal or superior to 3 (p=0.023) and the procedure 'Posterior Spinal Fusion' (p=0.001) were associated with a higher frequency of AEs. AEs required prolonged LOS in 40 cases, 7 (70%) pediatric patients and 33 (65%) adults. Discussion and Conclusion: The overall prevalence of AEs is 20.8%, and, although the distribution is almost equal between adult and pediatric patients, their severity is related to age, being higher in pediatric patients. Deformities, deformity correction, revision surgery and AP surgery are the most impactful factors. AEs seriously affect hospitalization, with prolonged LOS (mean 6 days).

Spinal cord stimulator medullary compression-a very rare SCS complication and surgical treatment.

INTRODUCTION: The risk of spinal cord damage after Spinal Cord Stimulator (SCS) implant is a very rare event. In our case report, the patient was affected by a progressively worsening spinal stenosis due to SCS compression. CASE REPORT: The authors describe a progressive paraparesis in a 58-year-old woman with a long history of back pain and multiple spine surgeries. Computed tomography (CT) outlined vertebral canal stenosis corresponding to an electrode array implanted in T9. A posterior T8-T10 spinal cord decompression with explanation of the SCS device was performed and a partial neurological improvement was observed immediately postoperative. DISCUSSION: Spinal cord stimulation has been used since 1967 for the treatment of refractory chronic pain, particularly failed back surgery syndrome (FBSS) and complex regional pain syndrome (CRPS). Still, the mechanism underlying its function is not completely clear. Moreover, complications are mainly related to implant dysfunction and the risk of direct and indirect spinal cord compression is described as exceptional in the literature. Our aim is to describe the case SCS device spinal cord direct compression and its surgical treatment.

Prediction of Long-Term Recovery From Disability Using Hemoglobin-Based Models: Results From a Cohort of 1,392 Patients Undergoing Spine Surgery.

Hemoglobin and its associated blood values are important laboratory biomarkers that mirror the strength of constitution of patients undergoing spine surgery. Along with the clinical determinants available during the preadmission visit, it is important to explore their potential for predicting clinical success from the patient's perspective in order to make the pre-admission visit more patient-centered. We analyzed data from 1,392 patients with spine deformity, disc disease, or spondylolisthesis enrolled between 2016 and 2019 in our institutional Spine Registry. Patient-reported outcome measure at 17 months after surgery was referred to the Oswestry disability index. High preoperative hemoglobin was found to be the strongest biochemical determinant of clinical success along with high red blood cells count, while low baseline disability, prolonged hospitalization, and long surgical times were associated with poor recovery. The neural network model of these predictors showed a fair diagnostic performance, having an area under the curve of 0.726 and a sensitivity of 86.79%. However, the specificity of the model was 15.15%, thus providing to be unreliable in forecasting poor patient-reported outcomes. In conclusion, preoperative hemoglobin may be one of the key biomarkers on which to build appropriate predictive models of long-term recovery after spine surgery, but it is necessary to include multidimensional variables in the models to increase the reliability at the patient's level.

Perioperative Anesthesia and Acute Smell Alterations in Spine Surgery: A "Sniffing Impairment" Influencing Refeeding?

Medications for general anesthesia can cause smell alterations after surgery, with inhalation anesthetics being the most acknowledged drugs. However, spine patients have been poorly studied in past investigations and whether these alterations could influence the refeeding remains unclear. This research aims to observe detectable dysosmias after spine surgery, to explore any amplified affection of halogenates (DESflurane and SEVoflurane) against total intravenous anesthesia (TIVA), and to spot potential repercussions on the refeeding. Fifty patients between 50 and 85 years old were recruited before elective spine procedure and tested for odor acuity and discrimination using the Sniffin' Sticks test. The odor abilities were re-assessed within the first 15 h after surgery together with the monitoring of food intakes. The threshold reduced from 4.92 ± 1.61 to 4.81 ± 1.64 (p = 0.237) and the discrimination ability reduced from 10.50 ± 1.83 to 9.52 ± 1.98 (p = 0.0005). Anesthetic-specific analysis showed a significant reduction of both threshold (p = 0.004) and discrimination (p = 0.004) in the SEV group, and a significant reduction of discrimination abilities (p = 0.016) in the DES group. No dysosmias were observed in TIVA patients after surgery. Food intakes were lower in the TIVA group compared to both DES (p = 0.026) and SEV (p = 0.017). The food consumed was not associated with the sniffing impairment but appeared to be inversely associated with the surgical time. These results confirmed the evidence on inhalation anesthetics to cause smell alterations in spine patients. Furthermore, the poor early oral intake after complex procedures suggests that spinal deformity surgery could be a practical challenge to early oral nutrition.

Delayed postoperative cervical spinal cord ischemic lesion after a thoracolumbar fusion for syndromic scoliosis: a case report and systematic review of the literature.

INTRODUCTION: We report a case and a literature review of delayed postoperative cervical spinal cord injury after thoraco-lumbar spine surgery. CASE REPORT: A 13-year-old Prader-Willi Syndrome female was treated by a T3-L5 posterior spine fusion for progressive scoliosis. Intraoperative neuromonitoring and immediate postoperative neurological examination were normal. Sixty hours after surgery, she developed a tetraplegia. The immediate MRI and CT scan of the spine were negative. Two days after, a new MRI revealed an ischemic cervical lesion at the level C5-C6. After 1 week, she gradually improved breathing and motility/sensibility at the extremities. After 4 months of intensive neurologic rehabilitation, the patient improved to ASIA grade D and was discharged. At 1-year follow, the neurologic recovery was nearly completed. METHODS: We performed a systematic review of the literature through PubMed and Embase database focused on delayed postoperative cervical spinal cord lesion after a thoraco-lumbar fusion for spinal deformity. RESULTS: Only 14 cases of neurological injuries at levels above the site of surgery have been previously reported and never in Prader Willy Syndrome. All patients were adolescent and 86,7% were females but no specific risk factors were found. CONCLUSIONS: Delayed postoperative neurological deficit far from the surgical site can be considered a specific subgroup of these rare complication that can occur several hours after spine surgery, regardless of intraoperative complication. Despite the rarity of this complication, clinicians should be aware of it. Perioperative optimization of spinal cord perfusion and close neurological examination in first postoperative days may be helpful to quickly recognize and treat this complication.

Multimodal exercises integrated with cognitive-behavioural therapy improve disability of patients with failed back surgery syndrome: a randomized controlled trial with one-year follow-up.

PURPOSE: To evaluate the effect of multimodal exercises integrated with cognitive-behavioural therapy on disability, pain, and quality of life in patients suffering from failed back surgery syndrome (FBSS), and to appraise its extent in the long term. METHODS: By means of a parallel-group superiority-controlled trial, 150 outpatients were randomly assigned to a 10-week individual-based multimodal programme of task-oriented exercises integrated with cognitive-behavioural therapy (experimental group, 75 patients) or individual-based general physiotherapy (control group, 75 patients). Before treatment, 10 weeks later (post-treatment), and 12 months after the end of treatment, the Oswestry Disability Index (primary outcome), the Tampa Scale for Kinesiophobia, the Pain Catastrophising Scale, a pain intensity numerical rating scale and the Short-Form Health Survey were evaluated. Linear mixed model analysis for repeated measures was carried out for each outcome measure. RESULTS: Significant group (p < 0.001), time (p < 0.001), and time-by-group interaction (p < 0.001) effects were found for all outcome measures. Concerning disability, between-group differences (95% confidential interval) in favour of the experimental group of -9 (-10.7; -7.3) after training and of -13.2 (-14.7; -11.7) at follow-up were found. Also, kinesiophobia, catastrophising and pain showed significant between-group differences of 9, 12.5 and 1.7 points, respectively. CONCLUSION: The multimodal intervention proposed was superior to general physiotherapy in reducing disability, kinesiophobia, catastrophising, and enhancing the quality of life of patients with FBSS. The effects were reinforced one year after the programme ended.IMPLICATIONS FOR REHABILITATIONMultimodal exercises integrated with cognitive-behavioural therapy induced significant improvements in disability, pain, kinesiophobia, catastrophising, and quality of life of subjects with Failed Back Surgery Syndrome.A well-integrated rehabilitative team which contributes towards reaching intervention goals is advised.Physiotherapists should adopt task-oriented exercises to promote an earlier return to common activities of disabled patients.Psychologists should explain how to modify useless beliefs and support adequate behaviours, in order to produce constructive attitudes towards perceived disability.

The Influence of Baseline Clinical Status and Surgical Strategy on Early Good to Excellent Result in Spinal Lumbar Arthrodesis: A Machine Learning Approach.

The study aims to create a preoperative model from baseline demographic and health-related quality of life scores (HRQOL) to predict a good to excellent early clinical outcome using a machine learning (ML) approach. A single spine surgery center retrospective review of prospectively collected data from January 2016 to December 2020 from the institutional registry (SpineREG) was performed. The inclusion criteria were age ≥ 18 years, both sexes, lumbar arthrodesis procedure, a complete follow up assessment (Oswestry Disability Index-ODI, SF-36 and COMI back) and the capability to read and understand the Italian language. A delta of improvement of the ODI higher than 12.7/100 was considered a "good early outcome". A combined target model of ODI (Δ ≥ 12.7/100), SF-36 PCS (Δ ≥ 6/100) and COMI back (Δ ≥ 2.2/10) was considered an "excellent early outcome". The performance of the ML models was evaluated in terms of sensitivity, i.e., True Positive Rate (TPR), specificity, i.e., True Negative Rate (TNR), accuracy and area under the receiver operating characteristic curve (AUC ROC). A total of 1243 patients were included in this study. The model for predicting ODI at 6 months' follow up showed a good balance between sensitivity (74.3%) and specificity (79.4%), while providing a good accuracy (75.8%) with ROC AUC = 0.842. The combined target model showed a sensitivity of 74.2% and specificity of 71.8%, with an accuracy of 72.8%, and an ROC AUC = 0.808. The results of our study suggest that a machine learning approach showed high performance in predicting early good to excellent clinical results.

How SARS-CoV-2 Pandemic Changed Traumatology and Hospital Setting: An Analysis of 498 Fractured Patients.

BACKGROUND: SARS-CoV-2 pandemic is one of the biggest challenges for many health systems in the world, making lots of them overwhelmed by the enormous pressure to manage patients. We reported our Institutional Experience, with specific aims to describe the distribution and type of treated injuries, and the organizational setup of our hospital. METHODS: Data of fractured patients admitted for surgical treatment in the time frames 9 March 2020-4 May 2020 and 1 March 2019-31 May 2019 were collected and compared. Furthermore, surgery duration and some parameters of effectiveness in health management were compared. RESULTS: A total of 498 patients were included. Mean age significantly lower age in 2019 and femoral fractures were significantly more frequent 2020. Mean surgery time was significantly longer in 2020. Mortality rate difference between the two years was found to be statistically significant. Time interval between diagnosis and surgery and between diagnosis and discharge/decease was significantly lower in 2020. In 2020, no patient admitted with a negative swab turned positive in any of the following tests for SARS-CoV-2. CONCLUSIONS: The COVID-19 pandemic has modified the epidemiology of hospitalized patients for traumatic reasons, leading to an increased admission of older patients with femoral fractures. Nevertheless, our institutional experience showed that an efficient change in the hospital organization, with an improvement of several parameters of effectiveness in health management, led to a null infection rate between patients.

Adipose-Derived Mesenchymal Stromal Cells Treated with Interleukin 1 Beta Produced Chondro-Protective Vesicles Able to Fast Penetrate in Cartilage.

The study of the miRNA cargo embedded in extracellular vesicles (EVs) released from adipose-derived mesenchymal stromal cells (ASC) preconditioned with IL-1ß, an inflammatory stimulus driving osteoarthritis (OA), along with EVs-cartilage dynamic interaction represent poorly explored fields and are the purpose of the present research. ASCs were isolated from subcutaneous adipose tissue and EVs collected by ultracentrifugation. Shuttled miRNAs were scored by high-throughput screening and analyzed through bioinformatics approach that predicted the potentially modulated OA-related pathways. Fluorescently labeled EVs incorporation into OA cartilage explants was followed in vitro by time-lapse coherent anti-Stokes Raman scattering; second harmonic generation and two-photon excited fluorescence. After IL-1ß preconditioning, 7 miRNA were up-regulated, 4 down-regulated, 37 activated and 17 silenced. Bioinformatics allowed to identify miRNAs and target genes mainly involved in Wnt, Notch, TGFß and Indian hedgehog (IHH) pathways, cartilage homeostasis, immune/inflammatory responses, cell senescence and autophagy. As well, ASC-EVs steadily diffuse in cartilage cells and matrix, reaching a plateau 16 h after administration. Overall, ASCs preconditioned with IL-1ß allows secretion of EVs embedded with a chondro-protective miRNA cargo, able to fast penetrate in collagen-rich areas of cartilage with tissue saturation in a day. Further functional studies exploring the EVs dose-effects are needed to achieve clinical relevance.

Load-sharing biomechanics of lumbar fixation and fusion with pedicle subtraction osteotomy.

Pedicle subtraction osteotomy (PSO) is an invasive surgical technique allowing the restoration of a well-balanced sagittal profile, however, the risks of pseudarthrosis and instrumentation breakage are still high. Literature studied primary stability and posterior instrumentation loads, neglecting the load shared by the anterior column, which is fundamental to promote fusion early after surgery. The study aimed at quantifying the load-sharing occurring after PSO procedure across the ventral spinal structures and the posterior instrumentation, as affected by simple bilateral fixation alone, with interbody cages adjacent to PSO level and supplementary accessory rods. Lumbar spine segments were loaded in vitro under flexion-extension, lateral bending, and torsion using an established spine tester. Digital image correlation (DIC) and strain-gauge (SG) analyses measured, respectively, the full-field strain distribution on the ventral surface of the spine and the local strain on posterior primary rods. Ventral strains considerably decreased following PSO and instrumentation, confirming the effectiveness of posterior load-sharing. Supplemental accessory rods considerably reduced the posterior rod strains only with interbody cages, but the ventral strains were unaffected: this indicates that the load transfer across the osteotomy could be promoted, thus explaining the higher fusion rate with decreased rod fracture risk reported in clinical literature.

Does Capacitively Coupled Electric Fields Stimulation Improve Clinical Outcomes After Instrumented Spinal Fusion? A Multicentered Randomized, Prospective, Double-Blind, Placebo-Controlled Trial.

BACKGROUND: Lumbar spinal fusion (LSF) is used to treat lumbar degenerative disorders. Methods to improve the functional recovery of patients undergoing LSF is one of the main goals in daily clinical practice. The objective of this study is to assess whether biophysical stimulation with capacitively coupled electric fields (CCEF) can be used as adjuvant therapy to enhance clinical outcome in LSF-treated patients. METHODS: Forty-two patients undergoing LSF were assessed and randomly allocated to either the active or to the placebo group. Follow-up visits were performed at 1, 3, 6, and 12 months after surgery; long-term follow-up was performed at year 10. Visual analogue scale (VAS), the Oswestry Disability Index (ODI), and the 36-item Short Form Health Survey (SF-36) questionnaire were recorded. RESULTS: This study demonstrates a significant improvement in CCEF-treated patients at 6 and 12 months' follow-up for SF-36, and at 12 months' follow-up for ODI values. Based on SF-36 and ODI scores, we reported a significantly higher percentage of successful treatments at 12 months in the active compared with the placebo group. Moreover, in a subset of patients at 10 years' follow-up, a significant difference was reported in VAS and ODI scores between groups. CONCLUSIONS: The results demonstrate that 3 months of CCEF treatment immediately after surgery is effective in reducing ODI and improving SF-36 score, and that these benefits can be maintained up to 12 months. In a subset of patients, these positive outcomes are retained up to 10 years. LEVEL OF EVIDENCE: I. CLINICAL RELEVANCE: This study suggests that CCEF stimulation can be used as an adjunct to LSF for spine diseases, for increasing overall quality of life and improving patients' functional recovery. CCEF is safe and well tolerated, compatible with activities of daily living.

Biomechanical in vitro comparison between anterior column realignment and pedicle subtraction osteotomy for severe sagittal imbalance correction.

PURPOSE: To investigate the biomechanical effects of anterior column realignment (ACR) and pedicle subtraction osteotomy (PSO) on local lordosis correction, primary stability and rod strains. METHODS: Seven cadaveric spine segments (T12-S1) underwent ACR at L1-L2. A stand-alone hyperlordotic cage was initially tested and then supplemented with posterior bilateral fixation. The same specimens already underwent a PSO at L4 stabilized by two rods, a supplemental central rod (three rods) and accessory rods (four rods) with and without adjacent interbody cages (La Barbera in Eur Spine J 27(9):2357-2366, 2018). In vitro flexibility tests were performed under pure moments in flexion/extension (FE), lateral bending (LB) and axial rotation (AR) to determine the range of motion (RoM), while measuring the rod strains with strain gauge rosettes. RESULTS: Local lordosis correction with ACR (24.7° ± 3.7°) and PSO (25.1° ± 3.9°) was similar. Bilateral fixation significantly reduced the RoM (FE: 31%, LB: 2%, AR: 18%), providing a stability consistent with PSO constructs (p > 0.05); however, it demonstrates significantly higher rod strains compared to PSO constructs with lateral accessory rods and interbody cages in FE and AR (p < 0.05), while being comparable in FE or slightly higher in AR compared to PSO constructs with two and three rods. CONCLUSION: Bilateral posterior fixation is highly recommended following ACR to provide adequate primary stability. However, primary rod strains in ACR were found comparable or higher than weak PSO construct associated with frequent rod failure; therefore, caution is recommended. These slides can be retrieved under Electronic Supplementary Material.