Ultrasound-triggered interfacial engineering-based microneedle for bacterial infection acne treatment.

Acne is an inflammatory skin disease mainly caused by Propionibacterium acnes, which can cause local inflammatory reactions and develop into chronic inflammatory diseases in severe cases. To avoid the use of antibiotics and to effectively treat the site of acne, we report a sodium hyaluronate microneedle patch that mediates the transdermal delivery of ultrasound-responsive nanoparticles for the effective treatment of acne. The patch contains nanoparticles formed by zinc porphyrin-based metal-organic framework and zinc oxide (ZnTCPP@ZnO). We demonstrated activated oxygen-mediated killing of P. acnes with an antibacterial efficiency of 99.73% under 15 min of ultrasound irradiation, resulting in a decrease in levels of acne-related factors, including tumor necrosis factor-α, interleukins, and matrix metalloproteinases. The zinc ions up-regulated DNA replication-related genes, promoting the proliferation of fibroblasts and, consequently, skin repair. This research leads to a highly effective strategy for acne treatment through the interface engineering of ultrasound response.

Does Diabetes Affect the Surgical Outcomes in Cases With Cervical Ossification of the Posterior Longitudinal Ligament? A Multicenter Study From Asia Pacific Spine Study Group.

STUDY DESIGN: Retrospective multicenter study. OBJECTIVES: To evaluate the surgical outcomes of cervical ossification of the posterior longitudinal ligament (OPLL) in diabetes mellitus (DM) patients. METHODS: Approximately 253 cervical OPLL patients who underwent surgical decompression with or without fixation were registered at 4 institutions in 3 Asian countries. They were followed up for at least 2 years. Demographics, imaging, and surgical information were collected, and cervical Japanese Orthopaedic Association (JOA) scores and the visual analog scale (VAS) for the neck were used for evaluation. RESULTS: Forty-seven patients had DM, showing higher hypertension and cardiovascular disease prevalence. Although they presented worse preoperative JOA scores than non-DM patients (10.5 ± 3.1 vs. 11.8 ± 3.2; P = 0.01), the former showed comparable neurologic recovery at the final follow-up (13.9 ± 2.9 vs. 14.2 ± 2.6; P = 0.41). No correlation was noted between the hemoglobin A1c level in the DM group and the pre- and postoperative JOA scores. No significant difference was noted in VAS scores between the groups at pre- and postsurgery. Regarding perioperative complications, DM patients presented a higher C5 palsy frequency (14.9% vs. 5.8%; P = 0.04). A similar trend was observed when surgical procedure was limited to laminoplasty. CONCLUSIONS: This is the first multicenter Asian study to evaluate the impact of DM on cervical OPLL patients. Surgical results were favorable even in DM cases, regardless of preoperative hemoglobin A1c levels or operative procedures. However, caution is warranted for the occurrence of C5 palsy after surgery.

Prevention of Surgical Site Infections in Spine Surgery: An International Survey of Clinical Practices Among Expert Spine Surgeons.

STUDY DESIGN: Questionnaire-based survey. OBJECTIVES: Surgical site infection (SSI) is a common complication in spine surgery but universal guidelines for SSI prevention are lacking. The objectives of this study are to depict a global status quo on implemented prevention strategies in spine surgery, common themes of practice and determine key areas for future research. METHODS: An 80-item survey was distributed among spine surgeons worldwide via email. The questionnaire was designed and approved by an International Consensus Group on spine SSI. Consensus was defined as more than 60% of participants agreeing to a specific prevention strategy. RESULTS: Four hundred seventy-two surgeons participated in the survey. Screening for Staphylococcus aureus (SA) is not common, whereas preoperative decolonization is performed in almost half of all hospitals. Body mass index (BMI) was not important for surgery planning. In contrast, elevated HbA1c level and hypoalbuminemia were often considered as reasons to postpone surgery. Cefazoline is the common drug for antimicrobial prophylaxis. Alcohol-based chlorhexidine is mainly used for skin disinfection. Double-gloving, wound irrigation, and tissue-conserving surgical techniques are routine in the operating room (OR). Local antibiotic administration is not common. Wound closure techniques and postoperative wound dressing routines vary greatly between the participating institutions. CONCLUSIONS: With this study we provide an international overview on the heterogeneity of SSI prevention strategies in spine surgery. We demonstrated a large heterogeneity for pre-, peri- and postoperative measures to prevent SSI. Our data illustrated the need for developing universal guidelines and for testing areas of controversy in prospective clinical trials.

Are clinical outcomes affected by laminoplasty method and K-line in patients with cervical ossification of posterior longitudinal ligament? A multicenter study.

BACKGROUND: Open-door laminoplasty (ODL) and French-door laminoplasty (FDL) are the main laminoplasty techniques used to treat cervical ossification of the posterior longitudinal ligament (C-OPLL). However, few studies have compared the outcomes of ODL and modified FDL (mFDL) for C-OPLL. We explored the differences in outcomes between ODL and mFDL for C-OPLL and analyzed the technical efficacy of each procedure in patients with K-line (+) or (-) C-OPLL. METHODS: From January 2010 to December 2015, 202 patients with K-line (+) or (-) C-OPLL were retrospectively recruited from 4 institutions. Clinical outcomes were evaluated using the Japanese Orthopaedic Association (JOA) score, JOA score recovery rate, operative time, blood loss, and complications. Univariate analysis and binary logistic regression models were adjusted for confounding factors. RESULTS: Two hundred patients (mFDL, n = 69; ODL, n = 131) with a median follow-up of 42 months (range 36-54 months) were included. The postoperative JOA score significantly improved in both groups (P < 0.05). After adjusting for confounding factors, there was a statistically significant difference in blood loss (≥ 300 mL) between the two groups (P = 0.005), but there was no significant difference in the postoperative JOA score (≥ 14) (P = 0.062), JOA score recovery rate (≥ 0.82) (P = 0.187), or operative time (≥ 90 min) (P = 0.925). C5 palsy tended to occur more often in the mFDL group, although the difference was not significant (P > 0.05). The stratified analysis of the K-line status showed more blood loss in K-line (+) patients who underwent mFDL, but there was no significant difference in the postoperative JOA score, JOA score recovery rate, or operative time between the ODL and mFDL groups. Additionally, there was no significant difference in blood loss, postoperative JOA score, JOA score recovery rate, or operative time among all patients with K-line (+) or (-) C-OPLL in both groups. CONCLUSIONS: Both ODL and mFDL are effective for patients with C-OPLL. However, more blood loss tends to occur during mFDL. This study showed no significant difference in the operative time or incidence of complications between the two techniques. The efficacy of ODL and mFDL was not affected by the K-line status (+ or -) in patients with C-OPLL.

Slow twitch paraspinal muscle dysregulation in adolescent idiopathic scoliosis exhibiting HIF-2α misexpression.

Background: Adolescent idiopathic scoliosis (AIS) refers to a three-dimensional spinal deformity which has a typical onset during adolescence. In most cases, the cause of the deformity cannot be clearly identified. Unbalanced paraspinal muscle activity in AIS patients was reported and hypoxia was implicated to regulate myogenesis. This study aims to investigate the association between myogenesis/muscle toning and HIF-αs activity in the pathogenesis of AIS. Methods: HIF-αs expression was examined by enzyme-linked immunosorbent assay and western blot in paraspinal myoblasts isolated from 18 subjects who underwent deformity correction surgery. QPCR was conducted to measure the gene expression levels of perinatal muscle fiber markers MYH3, MYH8; slow twitch muscle fiber markers MHY7; fast twitch muscle fiber markers MYH4; and myogenic regulatory factors MYF5 and MYOG. Slow and fast twitch muscle fiber composition in concave/convex paraspinal musculature of AIS subjects was evaluated by immunostaining of myosin heavy chain type I (MyHC I) and myosin heavy chain type II (MyHC II). Results: Reduced HIF-2α induction under hypoxia was found in paraspinal myoblast culture of 33% AIS subjects. We detected a suppression of perinatal and slow twitch muscle fiber associated genes, but not fast twitch muscle fiber-associated genes and myogenic regulatory factors in HIF-2α misexpressed AIS myoblasts. Distinct reduction of slow twitch muscle fiber was evidenced in convex paraspinal musculature, suggesting an asymmetric expression of slow twitch muscle fiber in HIF-2α misexpressed AIS patients. Conclusions: This study indicates an association of abnormal HIF-2α expression in paraspinal myoblasts and a disproportionate slow twitch muscle fiber content in the convexity of the curvature in a subset of AIS subjects, suggesting HIF-2α dysregulation as a possible risk factor for AIS. The role of HIF-2α in paraspinal muscle function during spinal growth and its relevance in AIS prognosis warrants further investigation.

Predictors of neurologic outcome after surgery for cervical ossification of the posterior longitudinal ligament differ based on myelopathy severity: a multicenter study.

OBJECTIVE: The purpose of this retrospective multicenter study was to compare prognostic factors for neurological recovery in patients undergoing surgery for cervical ossification of the posterior longitudinal ligament (OPLL) based on their presenting mild, moderate, or severe myelopathy. METHODS: The study included 372 consecutive patients with OPLL who underwent surgery for cervical myelopathy between 2006 and 2016 in East Asian countries with a high OPLL prevalence. Baseline and postoperative clinical outcomes were assessed using the Japanese Orthopaedic Association (JOA) myelopathy score and recovery ratio. Radiographic assessment included occupying ratio, cervical range of motion, and sagittal alignment parameters. Patient myelopathy was classified as mild, moderate, or severe based on the preoperative JOA score. Linear and multivariate regression analyses were performed to identify patient and surgical factors associated with neurological recovery stratified by baseline myelopathy severity. RESULTS: The mean follow-up period was 45.4 months (range 25-140 months). The mean preoperative and postoperative JOA scores and recovery ratios for the total cohort were 11.7 ± 3.0, 14.5 ± 2.7, and 55.2% ± 39.3%, respectively. In patients with mild myelopathy, only age and diabetes correlated with recovery. In patients with moderate to severe myelopathy, older age and preoperative increased signal intensity on T2-weighted imaging were significantly correlated with a lower likelihood of recovery, while female sex and anterior decompression with fusion (ADF) were associated with better recovery. CONCLUSIONS: Various patient and surgical factors are correlated with likelihood of neurological recovery after surgical treatment for cervical OPLL, depending on the severity of presenting myelopathy. Older age, male sex, intramedullary high signal intensity, and posterior decompression are associated with less myelopathy improvement in patients with worse baseline function. Therefore, myelopathy-specific preoperative counseling regarding prognosis for postoperative long-term neurological improvement should include consideration of these individual and surgical factors.

A comparison of six outcome measures across the recovery period after distal radius fixation-Which to use and when?

PURPOSE: Many standardized outcome measures exist to measure recovery after surgical fixation of distal radius fractures, however, choosing the optimal instrument is difficult. We evaluated responsiveness, ceiling/floor effects, and criterion validity over multiple time intervals across a 2-year follow-up period for six commonly used instruments. METHODS: A total of 259 patients who received open reduction and internal fixation for distal radius fractures between 2012 and 2015 were recruited. Patients were administered the Patient-Rated Wrist Evaluation (PRWE), Shortened Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH), Green and O'Brien score (Cooney modification) (CGNO), Gartland and Werley score (Sarmiento modification) (SGNW), flexion-extension arc (FEArc), and grip fraction test (GripFrac) at 1.5, 3, 6, 12, and 24 months postoperatively. Responsiveness was evaluated by calculating standardized response means (SRM) and Cohen's d effect sizes (ES), and by correlating each instrument's change scores against those of QuickDASH and PRWE, which were also used as external comparators to assess criterion validity. Ceiling/floor effects were calculated for all measures at each time point. RESULTS: SRM (1.5-24 months) were 1.81, 1.77, 1.43, 1.16, 2.23, 2.45 and ES (1.5-24 months) were 1.81, 1.82, 1.95, 1.31, 1.99 and 2.90 for QuickDASH, PRWE, CGNO, SGNW, FEArc, and GripFrac respectively. Spearman correlation coefficients against QuickDASH at 24 months were: 0.809, 0.248, 0.563, 0.285, and 0.318 for PRWE, CGNO, SGNW, FEArc, and GripFrac respectively. Significant (>15% of patients reaching maximum score) ceiling effects were observed before 6 months for PRWE and SGNW. CONCLUSIONS: Our evidence supports the use of QuickDASH, PRWE, FEArc and GripFrac up to 6 months postsurgery, and QuickDASH and PRWE after 6 months. LEVEL OF EVIDENCE: Level II.

Magnetically controlled growing rods in early onset scoliosis: radiological results, outcome, and complications in a series of 22 patients.

INTRODUCTION: Magnetically controlled growing rods (MCGR) for the surgical treatment of early onset scoliosis (EOS) allow non-invasive outpatient based distractions during spinal growth. The purpose of this study is to present the results of a single center case series of 22 patients, evaluate the effect of MCGR treatment on the development of spino-pelvic parameters during growth, and report initial outcomes after end of treatment. MATERIALS AND METHODS: Prospectively collected data of 22 EOS patients with MCGR treatment has been analyzed. The following radiological parameters were measured before index surgery, after index surgery, 1 year after index surgery, and at last follow-up: Cobb angle of the major curves, thoracic kyphosis (TK), lumbar lordosis (LL), sagittal vertical axis (SVA), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). Mean age at index surgery was 9.5 years (range: 4-14 years). Mean length of follow-up was 47.6 months (range: 25-121 months). Etiology of diagnosis was idiopathic in 14 patients, associated with neurofibromatosis in 2 patients, and neuromuscular or syndromic in 6 patients. RESULTS: Mean Cobb angle of the major curve was 57° preoperatively and 29° at last follow-up (p < 0.0005). Mean TK was 20.1° preoperatively and 20° at last follow-up (p > 0.05). Mean LL was 52.8° preoperatively and 53.2° at last follow-up (p > 0.05). Mean PI was 43.2° preoperatively and 46.3° at last follow-up (p > 0.05). Mean PT was 4.1° preoperatively and 5.8° at last follow-up (p > 0.05). Mean SS was 39.2° preoperatively and 41.7° at last follow-up (p > 0.05). 14 patients finished treatment: nine received final fusion and five received rod removal without fusion. Twelve complications occurred: one deep wound infection, six patients developed proximal junctional kyphosis (PJK), one rod fracture, two rods failed to distract, one deformity progressed after rod removal and required spinal fusion, and one patient developed autofusion of the spine prior to end of treatment. CONCLUSION: MCGR treatment is able to control deformity progression. Complication rate was 54.5%. Sagittal balance was not altered and treatment does not seem to have a negative impact on the development of spino-pelvic parameters during growth. Optimal end of treatment for the individual patient still has to be defined.

Brace Effectiveness Is Related to 3-Dimensional Plane Parameters in Patients with Adolescent Idiopathic Scoliosis.

BACKGROUND: Although scoliosis is a 3-dimensional (3D) deformity, little research has been performed on the use of 3D imaging in brace curve correction. The purpose of the present study was to determine the effect of axial-plane parameters on the outcomes of bracing with a thoracolumbosacral orthosis for adolescent idiopathic scoliosis. METHODS: This prospective longitudinal cohort study included patients with adolescent idiopathic scoliosis who fulfilled the criteria for bracing according to the Scoliosis Research Society, and was conducted from the time the patient began wearing the brace through a minimum follow-up of 2 years or until a surgical procedure was performed. Radiographs made with use of an EOS Imaging System were used to reconstruct 3D images of the spine at the pre-brace, immediate in-brace, 1-year in-brace, and latest follow-up out-of-brace stages. Univariate and multiple linear regressions were performed to determine the association between axial rotation correction and curve progression at the time of the latest follow-up. Logistic regressions were performed to model the probability of risk of progression. RESULTS: Fifty-three patients were enrolled, and 46 patients were included in the analysis. At the time of the latest follow-up, 30 patients did not experience curve progression and 16 patients had curve progression. There was no difference in baseline demographic characteristics between groups. For the transverse-plane parameters, there was a significant difference between non-progression and progression groups in pre-brace apical vertebral rotation (4.5° ± 11.2° compared with -2.4° ± 9.8°, respectively; p = 0.044) and in 1-year in-brace apical vertebral rotation correction velocity (2.0° ± 5.0°/year compared with -1.7° ± 4.4°/year, respectively; p = 0.016). Logistic regression analysis showed that pre-brace apical vertebral rotation (odds ratio, 1.063; 95% confidence interval, 1.000 to 1.131; p = 0.049) and 1-year in-brace apical vertebral rotation correction velocity (odds ratio, 1.19; 95% confidence interval, 1.021 to 1.38; p = 0.026) were associated with an increased risk of curve progression. There was no difference in Scoliosis Research Society 22-Item scores between patients who experienced curve progression and those who did not. CONCLUSIONS: In this prospective study, we demonstrated that axial-plane parameters and the correction of these parameters during bracing are related to the successful use of the brace. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Are Higher Global Alignment and Proportion Scores Associated With Increased Risks of Mechanical Complications After Adult Spinal Deformity Surgery? An External Validation.

BACKGROUND: The Global Alignment and Proportion (GAP) score, based on pelvic incidence-based proportional parameters, was recently developed to predict mechanical complications after surgery for spinal deformities in adults. However, this score has not been validated in an independent external dataset. QUESTIONS/PURPOSES: After adult spinal deformity surgery, is a higher GAP score associated with (1) an increased risk of mechanical complications, defined as rod fractures, implant-related complications, proximal or distal junctional kyphosis or failure; (2) a higher likelihood of undergoing revision surgery to treat a mechanical complication; and (3) is a lower (more proportioned) GAP score category associated with better validated outcomes scores using the Oswestry Disability Index (ODI), Scoliosis Research Society-22 (SRS-22) and the Short Form-36 questionnaires? METHODS: A total of 272 patients who had undergone corrective surgeries for complex spinal deformities were enrolled in the Scoli-RISK-1 prospective trial. Patients were included in this secondary analysis if they fulfilled the original inclusion criteria by Yilgor et al. From the original 272 patients, 14% (39) did not satisfy the radiographic inclusion criteria, the GAP score could not be calculated in 14% (37), and 24% (64) did not have radiographic assessment at postoperative 2 years, leaving 59% (159) for analysis in this review of data from the original trial. A total of 159 patients were included in this study,with a mean age of 58 ± 14 years at the time of surgery. Most patients were female (72%, 115 of 159), the mean number of levels involved in surgery was 12 ± 4, and three-column osteotomy was performed in 76% (120 of 159) of patients. The GAP score was calculated using parameters from early postoperative radiographs (between 3 and 12 weeks) including pelvic incidence, sacral slope, lumbar lordosis, lower arc lordosis and global tilt, which were independently obtained from a computer software based on centralized patient radiographs. The GAP score was categorized as proportional (scores of 0 to 2), moderately disproportional (scores of 3 to 6), or severely disproportional (scores higher than 7 to 13). Receiver operating characteristic area under curve (AUC) was used to assess associations between GAP score and risk of mechanical complications and risk of revision surgery. An AUC of 0.5 to 0.7 was classified as "no or low associative power", 0.7 to 0.9 as "moderate" and greater than 0.9 as "high". We analyzed differences in validated outcome scores between the GAP categories using Wilcoxon rank sum test. RESULTS: At a minimum of 2 years' follow-up, a higher GAP score was not associated with increased risks of mechanical complications (AUC = 0.60 [95% CI 0.50 to 0.70]). A higher GAP score was not associated with a higher likelihood of undergoing a revision surgery to treat a mechanical complication (AUC = 0.66 [95% 0.53 to 0.78]). However, a moderately disproportioned GAP score category was associated with better SF-36 physical component summary score (36 ± 10 versus 40 ± 11; p = 0.047), better SF-36 mental component summary score (46 ± 13 versus 51 ± 12; p = 0.01), better SRS-22 total score (3.4 ± 0.8 versus 3.7 ± 0.7, p = 0.02) and better ODI score (35 ± 21 versus 25 ± 20; p = 0.003) than severely disproportioned GAP score category. CONCLUSION: Based on the findings of this external validation study, we found that alignment targets based on the GAP score alone were not associated with increased risks of mechanical complications and mechanical revisions in patients with complex adult spinal disorders. Parameters not included in the original GAP score needed to be considered to reduce the likelihood of mechanical complications. LEVEL OF EVIDENCE: Level III, diagnostic study.

Systematic investigation of metallosis associated with magnetically controlled growing rod implantation for early-onset scoliosis.

AIMS: To investigate metallosis in patients with magnetically controlled growing rods (MCGRs) and characterize the metal particle profile of the tissues surrounding the rod. METHODS: This was a prospective observational study of patients with early onset scoliosis (EOS) treated with MCGRs and undergoing rod exchange who were consecutively recruited between February 2019 and January 2020. Ten patients were recruited (mean age 12 years (SD 1.3); 2 M:8 F). The configurations of the MCGR were studied to reveal the distraction mechanisms, with crucial rod parts being the distractable piston rod and the magnetically driven rotor inside the barrel of the MCGR. Metal-on-metal contact in the form of ring-like wear marks on the piston was found on the distracted portion of the piston immediately outside the barrel opening (BO) through which the piston rod distracts. Biopsies of paraspinal muscles and control tissue samples were taken over and away from the wear marks, respectively. Spectral analyses of the rod alloy and biopsies were performed to reveal the metal constituents and concentrations. Histological analyses of the biopsies were performed with haematoxylin and eosin staining. RESULTS: Titanium (Ti), vanadium (V), and neodymium (Nd) concentrations in the biopsies taken near the wear marks were found to be significantly higher than those in the control tissue samples. Significantly increased Nd concentrations were also found in the tissues near the barrel of the MCGR. Chronic inflammation was revealed by the histological studies with fibrosis and macrophage infiltration. Black particles were present within the macrophages in the fibrotic tissues. CONCLUSION: Ti and V were generated mainly at the BO due to metal-on-metal contact, whereas the Nd from the rotor of the MCGR is likely released from the BO during distraction sessions. Phagocytotic immune cells with black particles inside raise concern regarding the long-term implications of metallosis. Cite this article: Bone Joint J 2020;102-B(10):1375-1383.

Complications following surgery for adolescent idiopathic scoliosis over a 13-year period.

AIMS: The purpose of this study was to evaluate the incidence and analyze the trends of surgeon-reported complications following surgery for adolescent idiopathic scoliosis (AIS) over a 13-year period from the Scoliosis Research Society (SRS) Morbidity and Mortality database. METHODS: All patients with AIS between ten and 18 years of age, entered into the SRS Morbidity and Mortality database between 2004 and 2016, were analyzed. All perioperative complications were evaluated for correlations with associated factors. Complication trends were analyzed by comparing the cohorts between 2004 to 2007 and 2013 to 2016. RESULTS: Between 2004 and 2016, a total of 84,320 patients were entered into the database. There were 1,268 patients associated with complications, giving an overall complication rate of 1.5%. Death occurred in 12 patients (0.014%). The three most commonly reported complications were surgical site infection (SSI) (441 patients; 0.52%), new neurological deficit (293; 0.35%), and implant-related complications (172; 0.20%). There was a statistically significant but weak correlation between the occurrence of a SSI and the magnitude of the primary curve (r = 0.227; p < 0.001), and blood loss in surgery (r = 0.111; p = 0.038), while the occurrence of a new neurological deficit was correlated statistically significantly but weakly with age at surgery (r = 0.147; p = 0.004) and magnitude of the primary curve (r = 0.258; p < 0.001). The overall complication rate decreased from 4.95% during 2004 to 2007 to 0.98% during 2013 to 2016 (p = 0.023). CONCLUSION: An overall complication rate of 1.5% was found in our series after surgery for AIS, with a reduction of complication rates found in the second period of the analysis. Cite this article: Bone Joint J 2020;102-B(4):519-523.

The Crooked Rod Sign: A New Radiological Sign to Detect Deformed Threads in the Distraction Mechanism of Magnetically Controlled Growing Rods and a Mode of Distraction Failure.

STUDY DESIGN: Case report. OBJECTIVE: To report a unique mechanical failure of magnetically controlled growing rods (MCGRs) that is related to continuous rod slippage. SUMMARY OF BACKGROUND DATA: Despite the growing popularity of MCGR in the management of patients with early onset scoliosis, postoperative complications and reoperations are not uncommon. Unique complications or unplanned reoperations are observed in patients with MCGRs that are not seen in traditional growing rods. The complications include rod slippage, mismatch between targeted and achieved distraction length, metallosis, and actuator pin fracture. We have identified an unreported failure mechanism whereby deformed threads occur in the internal distraction mechanism of the MCGR. This phenomenon may indicate increased MCGR internal screw friction and increased distraction resistance. Increased friction and resistance ultimately led to distraction failure and revision surgery. METHODS: A girl with early onset scoliosis (EOS) was treated by dual MCGRs. She developed proximal junctional kyphosis (PJK) and continuous rod slippage. Distractions in the out-patient clinic and under sedation did not achieve successful rod lengthening. A tell-tale "crooked rod" radiological sign was identified by angulation between the actuator and the extendable portion of the rod. RESULTS: Rod exchange was performed and she is now 2 years after revision surgery with successful lengthening episodes. Upon review of the extracted MCGR, distraction was not possible even after rod removal and was only resumed after the screw was manually reinserted along its correct threads. CONCLUSION: Deformed threads is a complication that cannot be reverted without rod removal and exchange. Users should be aware of this potential failure mechanism and proceed to early rod exchange rather than attempting any further distractions. LEVEL OF EVIDENCE: 4.

Selection of Lowest Instrumented Vertebra Using Fulcrum Bending Radiographs Achieved Shorter Fusion Safely Compared With the Last "Substantially" Touching Vertebra in Lenke Type 1A and 2A Curves.

STUDY DESIGN: Retrospective study with prospective radiographic data collection. OBJECTIVE: To compare fusion level determination criteria using the fulcrum bending radiograph (FBR) and the last substantially touched vertebra (STV) as the lowest instrumented vertebra (LIV) in the radiographic outcomes of correction surgery for Lenke 1A and 2A scoliosis patients with a minimum of 2-year follow-up. SUMMARY OF BACKGROUND DATA: The STV has been proposed as the LIV in Lenke 1A and 2A curves to avoid postoperative distal adding-on. However, the influence of the inherent flexibility of the curves on selecting the LIV in relation to the STV is not known. METHODS: A total of 65 consecutive Lenke 1A and 2A patients who underwent posterior selective thoracic fusion were included in this study with a minimum of 2-year follow-up. LIV determination was compared with the FBR and STV methods. The curve correction, trunk shift, radiographic shoulder height, list, and the incidence of distal adding-on were documented. RESULTS: Mean preoperative, postoperative, and final follow-up standing coronal Cobb angles of primary curves were 59.37°, 15.58°, and 16.62° respectively. Using the FBR to determine the LIV, STV was selected in 16 patients (25%), STV-1 in 34 (52%), STV-2 in 11 (17%), and STV-3 in three (5%). Fusion level difference between using FBR and STV method was statistically significantly larger (P = 0.019) in patients with more than 70% fulcrum flexibility (mean: 1.18 levels, range: 0-3 levels) than those with less than or equal to 70% flexibility (mean: 0.70 level, range: -1 to 3 levels). Mean fulcrum flexibility was 73.9% in patients who achieved a shorter fusion by FBR method and 66.3% in patients who did not achieve a shorter fusion. Adding-on was observed in three patients (4.6%). CONCLUSION: By considering the curve flexibility, LIV determination using FBR method achieved a shorter fusion than STV method in over 70% of Lenke 1A and 2A patients, while being safe and effective at 2-year follow-up. LEVEL OF EVIDENCE: 3.

Cardiopulmonary Function in Patients with Congenital Scoliosis: An Observational Study.

BACKGROUND: Patients with congenital scoliosis often have restrictive pulmonary dysfunction on static pulmonary function testing (PFT). Although frequently asymptomatic during daily activities, these patients are generally assumed to have reduced exercise capacity. The aim of this study was to use dynamic cardiopulmonary exercise testing (CPET) to investigate exercise capacity and its association with spinal deformity in patients with congenital scoliosis. METHODS: Sixty patients with congenital scoliosis who underwent preoperative spinal radiography, PFT, and CPET were included from January 2014 to November 2017. The impact of thoracic spinal deformity and rib anomalies on pulmonary function and physical capacity was investigated. RESULTS: A significant deterioration in pulmonary function with increases in the severity of the major thoracic curve was demonstrated by the forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and total lung capacity (all p < 0.001). The ratio of FEV1 to FVC was similar regardless of thoracic curve severity. A smaller tidal volume during exercise testing reflected restrictive dysfunction in the patients with the most severe curves. CPET also revealed a significant trend of faster breathing by patients with a severe thoracic curve (p < 0.001). Exercise capacity indicators such as work rate (p = 0.019), heart rate (p = 0.015), and oxygen saturation (p = 0.006) were significantly reduced only in patients with a thoracic curve of >100°. Pulmonary dysfunction was the major contributor to exercise intolerance. Compared with mild pulmonary dysfunction, moderate and severe dysfunction was associated with an abnormal breathing pattern and lower work rate (p = 0.032) and peak oxygen intake (p = 0.042), indicating worse exercise tolerance. CONCLUSIONS: Congenital scoliosis leads to restrictive pulmonary dysfunction, which reduces the tidal volume and forces patients to accelerate respiratory rates during exercise. Patients with a thoracic curve of >100° are unable to compensate and have significantly reduced exercise capacity. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Mean 6-Year Follow-up of Magnetically Controlled Growing Rod Patients With Early Onset Scoliosis: A Glimpse of What Happens to Graduates.

BACKGROUND: There is no agreement on frequency of distractions of magnetically controlled growing rods (MCGRs) but more frequent and smaller amounts of distractions mimic physiological spine growth. The mid- to long-term follow-up and management at skeletal maturity is unknown. OBJECTIVE: To analyze patients with mean 6 yr of follow-up and describe the fate of MCGR graduates. METHODS: Early onset scoliosis (EOS) patients treated with MCGRs with minimum 4 yr of follow-up and/or at graduation were studied. Parameters under study included Cobb angle, spine and instrumented lengths, and rod distraction gains. Relationship between timing of rod exchanges with changes in rate of lengthening was studied. RESULTS: Ten EOS patients with mean 6.1 yr of follow-up were studied. The greatest Cobb angle correction occurred at the initial implantation surgery and was stable thereafter. Consistent gains in T1-12, T1-S1, and instrumented segment were observed. Rate of lengthening reduced after the first year of use but improved back to initial rates after rod exchange. Seven of the ten patients experienced complications with reoperation rate of 40% for rod distraction failure and proximal foundation problems. Only mild further improvements in all radiological parameters were observed pre- and postfinal surgery. No clinically significant curve progression was observed for rod removal only. All postfinal surgery parameters remained similar at postoperative 2 yr. CONCLUSION: This study provides an outlook of the end of MCGR treatment. Although this is a fusionless procedure, instrumented segments do experience stiffness limiting further correction and length gain during final surgery whether fusion or rod removal is performed.

Vertebral Growth Around Distal Instrumented Vertebra in Patients With Early-Onset Scoliosis Who Underwent Traditional Dual Growing Rod Treatment.

STUDY DESIGN: Retrospective radiographic study. OBJECTIVE: To investigate the growth of the vertebrae around distal instrumented vertebra (DIV) in patients with early-onset scoliosis (EOS) who underwent dual growing rod (DGR) treatment. SUMMARY OF BACKGROUND DATA: Previous studies indicated that DGR was likely to preserve or even stimulate the spinal growth. However, report pertaining to the effect of growing rod on the growth of individual vertebral body is rare. METHODS: The EOS patients treated with DGR who had at least four lengthenings and 5-year follow-up were enrolled. Spine radiographs at index surgery and final follow-up were reviewed. The height, width, and depth of vertebral body from DIV-2 to DIV+2, and the height of the adjacent intervertebral space (IVS) were measured. The percentage of growth was calculated. RESULTS: Thirty-one patients (mean age, 6.2 ±â€Š2.5 years old) met the inclusion criteria, 74.2% (23/31) of whom were female. The average follow-up was 6.2 years (range, 5.0-10.4 yr). The measured vertebrae were divided into DIV group (n = 65), DIV- group (DIV-1 and DIV-2, n = 60), and DIV+ group (DIV+1 and DIV+2, n = 47). There were 33, 90, and 78 measured IVSs in DIV, DIV-, and DIV+ group, respectively. The total percentage growth of vertebral height was significantly higher in DIV- group than that in DIV and DIV+ groups (56.6 ±â€Š20.3% vs. 45.6 ±â€Š18.0% and 42.7 ±â€Š16.2%, respectively, P ≤ 0.001). The vertebrae in DIV- group also had the highest annual height growth rate (8.7 ±â€Š2.6% vs. 7.0 ±â€Š2.4% and 6.6 ±â€Š2.0%, respectively, P ≤ 0.001). A significant decrease of IVS height was observed in DIV- and DIV groups (P ≤ 0.001). CONCLUSION: Traditional DGR with periodical distraction stimulated the longitudinal growth of the two segments immediately above DIV in patients with EOS. DGR technique had a negative effect on the development of intervertebral discs within distracted levels. LEVEL OF EVIDENCE: 3.

Non-neurologic adverse events after complex adult spinal deformity surgery: results from the prospective, multicenter Scoli-RISK-1 study.

PURPOSE: Accurate information regarding the expected complications of complex adult spinal deformity (ASD) is important for shared decision making and informed consent. The purpose of the present study was to investigate the rate and types of non-neurologic adverse events after complex ASD surgeries, and to identify risk factors that affect their occurrence. METHODS: The details and occurrence of all non-neurologic adverse events were reviewed in a prospective cohort of 272 patients after complex ASD surgical correction in a mulitcentre database of the Scoli-RISK-1 study with a planned follow-up of 2 years. Logistic regression analyses were used to identify potential risk factors for non-neurologic adverse events. RESULTS: Of the 272 patients, 184 experienced a total of 515 non-neurologic adverse events for an incidence of 67.6%. 121 (44.5%) patients suffered from more than one adverse event. The most frequent non-neurologic adverse events were surgically related (27.6%), of which implant failure and dural tear were most common. In the unadjusted analyses, significant factors for non-neurologic adverse events were age, previous spine surgery performed, number of documented non-neurologic comorbidities and ASA grade. On multivariable logistic regression analysis, previous spine surgery was the only independent risk factor for non-neurologic adverse events. CONCLUSIONS: The incidence of non-neurologic adverse events for patients undergoing corrective surgeries for ASD was 67.6%. Previous spinal surgery was the only independent risk factor predicting the occurrence of non-neurologic adverse events. These findings complement the earlier report of neurologic complications after ASD surgeries from the Scoli-RISK-1 study. These slides can be retrieved under Electronic Supplementary Material.

Prediction of survival in patients with symptomatic spinal metastases: Comparison between the Tokuhashi score and expert oncologists.

BACKGROUND: Existing scoring systems have suboptimal accuracy in prognosticating patients with spinal metastases. Currently, there is no superior method in predicting survival. This study aims to compare the accuracy of survival prediction by expert oncologists versus the revised Tokuhashi scores with actual survivals in a cohort of symptomatic spinal metastases patients. METHODS: All patients who underwent surgical treatment for metastatic spinal tumours in a tertiary hospital between January 2011 to December 2015 were reviewed. Each patient's data was reconstructed into an anonymised clinical scenario and presented independently to five blinded attending oncologists with at least three years' post fellowship experience. They were surveyed for survival prediction twice at no less than four weeks' interval apart; the test-retest reliability was examined. The agreement of their prognostication and modified Tokuhashi scores were compared with actual survivals. RESULTS: Fifty-five patients were included during the study period. The mean age at presentation was 61.1 years (range, 41 to 79), and mean actual survival was 21.6 months (range, 1 to 68). Cohen's kappa agreement with actual survival was higher by oncologists' estimation (0.52) than by revised Tokuhashi score prediction (0.31) (p = 0.018). Intra-class correlation showed high inter-reliability (0.71) between the five oncologists and a high test-retest reliability (0.69) between both rounds of the survey. CONCLUSION: This study showed that expert oncologists provided more accurate survival prediction than revised Tokuhashi scores in patients with spinal metastases. Future studies are required to identify factors in their assessment that led to improved accuracy.