A Novel growth guidance system for early onset scoliosis: a preliminary in vitro study.

PURPOSE: The purpose of the study was to describe a novel growth guidance system, which can avoid metal debris and reduce the sliding friction forces, and test the durability and glidability of the system by in vitro test. METHOD: Two major modifications were made to the traditional Shilla system, including the use of ultra-high molecular weight polyethylene (UHMWPE) gaskets to avoid direct contact between the screw and rod, and polishing the surface of the sliding part of the rod. We tested the durability of the system by a fatigue test, which the samples were test on the MTS system for a 10 million cycle of a constant displacement. Pre and post-testing involved weighing the UHMWPE gaskets and observing the wear conditions. The sliding ability were measured by a sliding displacement test. The maximum sliding displacement of the system was measured after a 300 cycles of dynamic compressive loads in a sinusoidal waveform. RESULTS: After the fatigue test, all the UHMWPE gaskets samples showed some of the fretting on the edge of the inner sides, but its still isolated and avoided the friction between the screws and rods. There was no production of metallic fretting around the sliding screws and rods. The average wear mass of the UHMWPE gaskets was 0.002 ± 0.001 g, less than 1.7% of the original mass. In the sliding test, the novel growth guidance system demonstrated the best sliding ability, with an average maximum sliding distance(AMSD) of 35.75 ± 5.73 mm, significantly better than the group of the traditional Shilla technique(AMSD 3.65 ± 0.46 mm, P < 0.0001). CONCLUSION: In conclusion, we modified the Shilla technique and designed a novel growth guidance system by changing the friction interface of sliding screw and rod, which may significantly reduce the metallic debris and promote spine growth. The fatigue test and sliding dislocation test demonstrated the better durability and glidability of the system. An in vivo animal experiment should be performed to further verify the system.

Optimal time window for initiating cefuroxime surgical antimicrobial prophylaxis in spinal fusion surgery: a nested case-control study.

BACKGROUND CONTEXT: Surgical site infections (SSI) are one of the common complications following spinal fusion surgery. Unfortunately, several studies had shown conflicting results regarding optimal timing of surgical antimicrobial prophylaxis (SAP) administration. Due to limitations in population homogeneity and sample size, these studies have not provided significant statistical correlations or clear practical recommendations. PURPOSE: The purpose of the study was to investigate the impact of timing of cefuroxime SAP on the risk of SSI in patients undergoing spinal fusion surgery, and to determine the optimal timing of administration. DESIGN: Retrospective nested case-control study. PATIENT SAMPLE: We retrospectively analyzed consecutive patients who underwent spinal fusion surgery at our institution between October 2011 and October 2021. OUTCOME MEASURE: In the current study, the primary outcome measure was SSI. METHODS: This was a retrospective nested case-control study. All consecutive patients who underwent spinal fusion surgery at our institution between October 2011 and October 2021 formed a retrospective cohort. For each SSI case, 2 controls free of SSI at the time of the index date of their corresponding case were selected, matched by age, sex, and calendar year. Electronic record and radiographic data were reviewed retrospectively in electronic database. SAP related data included timing of administration, preoperative dose, intraoperative second dose, and postoperative use. To examine the effects of mismatched variables, we further adjusted for possible confounding factors using conditional logistic regression models. Subsequently, subgroup analyses were conducted to assess the robustness of the statistical associations. RESULTS: According to the pre-planned statistical scheme and matching factors, we matched 236 controls for these SSI cases, and the subsequent statistical analysis was performed on these 354 patients. After adjusting for confounding factors, the results indicated that the risk of SSI was 70% higher in the group receiving SAP 31 to 60 minutes before incision compared to the group receiving SAP 0 to 30 minutes before incision (OR=1.732, 95%CI 1.031-2.910, p=.038). Additionally, the risk of SSI was 150% higher in the group receiving SAP 61 to 120 minutes before incision compared to the group receiving SAP 0 to 30 minutes before incision (OR=2.532, 95%CI 1.250-5.128, p=.010). In subgroup analysis, this statistical trend persisted for both deformity surgeries and different SSI classifications. CONCLUSION: Administering cefuroxime SAP within 30 minutes before skin incision significantly reduces the risk of SSI, whether they are deep or superficial, in spinal fusion surgery. This pattern remains consistent among spinal deformity patients.

Early mobilization can reduce the incidence of surgical site infections in patients undergoing spinal fusion surgery: A nested case-control study.

BACKGROUND: To examine the influence of early mobilization on the risk of surgical site infections (SSI) in patients undergoing spinal fusion surgery. METHODS: The retrospective cohort consisted of all consecutive patients who underwent spinal fusion surgery at our institution. For each case of SSI, 2 control patients without SSI at the corresponding index date were selected. Mobilization was predefined as "delayed" if it occurred more than 36 hours postoperatively. To account for potential confounding variables, we performed further adjustments using conditional logistic regression models. Subgroup analyses were conducted to evaluate the robustness of the statistical associations. RESULTS: Following the predefined statistical protocol and matching criteria, we matched 236 control cases to the SSI cases. Upon adjustment for confounding factors, our findings revealed that the risk of SSI was 120% higher in the group beginning mobilization more than 36 hours after surgery compared to the group beginning mobilization within 36 hours postoperatively (odds ratio = 2.206, 95% confidence interval 1.169-4.166, P = .015). In subgroup analyses, this statistical trend remained consistent. CONCLUSIONS: Early mobilization within 36 hours following spinal fusion surgery significantly reduces the risk of SSI. This pattern of reduced risk remains consistent among patients with degenerative diseases or spinal deformities.

Effect Modification of COVID-19 Symptoms on the Association Between Timing of Surgery and Postoperative Complications in Pediatric Spinal Deformity: A Prospective Cohort Study.

OBJECTIVE: The purpose of this study was to explore the optimal timing and associated risks of pediatric spinal deformity surgery during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: All consecutive surgical cases for spinal deformity between September 2022 and May 2023 were included. The population was divided into several categories according to the time from diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection to the day of surgery. Postoperative complications were analyzed using logistic regression, and we simultaneously showed the results from the crude model, minimally adjusted model, and fully adjusted model. RESULTS: A total of 81 consecutive patients were enrolled. In the fully adjusted model, compared with pre-COVID-19 patients, peri-COVID-19 patients had a 4.5-fold increased risk of postoperative complications (odds ratio = 5.5, 95% confidence interval 1.1-27.2, P = 0.037), early post-COVID-19 patients had a 2.3-fold increased risk (odds ratio= 3.3, 95% confidence interval 0.7-16.1, P = 0.133), and late post-COVID-19 patients were at essentially equal risk. In asymptomatic population, early post-COVID-19 patients and late post-COVID-19 patients appeared to be at equal risk compared with pre-COVID-19 patients. For patients with persistent symptoms, is necessary to wait at least 8 weeks or even longer after SARS-CoV-2 infection. Interaction tests demonstrated that the effect of the timing of surgery on postoperative complications significantly differed in populations with different symptoms. CONCLUSIONS: Surgery for pediatric spinal deformity should be postponed until 8 weeks after SARS-CoV-2 infection in cases with COVID-19-related symptoms within 2 weeks prior to surgery; whereas, for those who are asymptomatic within 2 weeks prior to surgery, an interval of 4 weeks seemed to be sufficient.

Dual Growing Rods and the Apical Control Technique for Treating Congenital Early-Onset Scoliosis: Lessons Learned.

BACKGROUND: Congenital early-onset scoliosis (CEOS) is characterized by a spectrum of vertebral anomalies, including formation failures and segmentation failures at the apex segment, which makes CEOS different from other etiologies of early-onset scoliosis. To date, studies on patients who have graduated from CEOS treatment using traditional dual growing rods (TDGR) have been scarce, and the preliminary results of TDGR with or without the apical control technique (ACT) have varied. We therefore compared the final outcomes of patients with CEOS who graduated from TDGR with or without the ACT. METHODS: A retrospective study of patients with CEOS who had graduated from TDGR treatment performed from 2007 to 2020 was conducted. Graduation included final fusion or observation after reaching skeletal maturity. Patients were divided into the ACT-TDGR group (apical vertebrectomy and/or hemivertebrectomy with short fusion and TDGR) and the TDGR-only group. Demographic characteristics, radiographic data, patient-reported clinical outcomes, pulmonary function, and complications were analyzed. RESULTS: A total of 41 patients with CEOS were enrolled: 13 in the ACT-TDGR group and 28 in the TDGR-only group. The lengthening intervals were longer in the ACT-TDGR group (mean [and standard deviation], 1.26 ± 0.66 years) than in the TDGR-only group (0.80 ± 0.27 years). The preoperative main curve was larger in the ACT-TDGR group (80.53° ± 19.50°) than in the TDGR-only group (64.11° ± 17.50°). The residual curve was comparable between groups (26.31° ± 12.82° in the ACT-TDGR group compared with 27.76° ± 15.0° in the TDGR group) at the latest follow-up. The changes in apical vertebral rotation and thoracic rotation were significantly larger in the ACT-TDGR group. Patients had comparable T1-12 and T1-S1 heights, pulmonary function, and 22-item Scoliosis Research Society (SRS-22) scores at the latest follow-up. The mean number of mechanical-related complications per patient was lower in the ACT-TDGR group (0.77 ± 0.73) than in the TDGR-only group (1.54 ± 1.43). Seventeen patients underwent final fusion. CONCLUSIONS: In this small-scale study, we observed that both ACT-TDGR and TDGR-only could correct the deformity while allowing for spinal growth in patients with CEOS. ACT-TDGR yielded better correction in severe cases and did not have a deleterious effect on spinal height. A large number of cases will be needed to validate the clinical value of the ACT. LEVEL OF EVIDENCE: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Outcomes of Ponte osteotomy combined with posterior lumbar interbody fusion for reconstruction of coronal and sagittal balance in degenerative scoliosis.

PURPOSE: The purpose of the study was to evaluate the clinical efficacy and safety of using Ponte osteotomy combined with posterior lumbar interbody fusion in the treatment of patients with degenerative scoliosis. METHOD: The medical records and imaging data of degenerative scoliosis patients in our department from 2013 to 2022 were retrospectively collected. A total of 47 patients were included, including 16 male patients and 31 female patients. The mean follow-up was 47.8 months. Whole spine X-rays in the standing position were performed on all patients preoperatively, postoperatively, and at the latest follow-up. The length of hospital stay, complications, operative duration, estimated blood loss, instrumented segment, fused segment, clinical scores, and various radiological indicators were recorded. RESULTS: The coronal vertical axis improved from 3.1 ± 1.9 cm preoperatively to 1.2 ± 1.0 cm postoperatively with an average reduction of 1.9 ± 1.7 cm. The preoperative coronal Cobb angle was 18.1 ± 10.6°, the immediate postoperative Cobb angle was 6.6 ± 3.9°, and the Cobb angle at the last follow-up was 5.8 ± 3.7°. The sagittal vertical axis decreased from 5.6 ± 3.7 cm preoperatively to 2.7 ± 1.9 cm immediately after the operation and was well maintained at the last follow-up (3.1 ± 2.5 cm). Lumbar lordosis increased from 22.2 ± 10.2° preoperatively to 40.4 ± 8.3° postoperatively and 36.0 ± 8.8° at the last follow-up. The ODI score, VAS low back pain score, and VAS leg pain score were also improved to varying degrees. CONCLUSION: Ponte osteotomy combined with posterior lumbar interbody fusion can significantly improve coronal and sagittal plane deformities and postoperative functional scores in patients with adult degenerative scoliosis.

Prognostic Nutritional Index Is a Predictive Marker for Health-Related Quality of Life in Patients with Adult Degenerative Scoliosis.

Our aim was to ascertain whether the prognostic nutritional index (PNI), could predict the health-related quality of life (HRQOL) in patients with adult degenerative scoliosis (ADS) undergoing corrective surgery. We conducted a retrospective analysis of consecutive patients diagnosed with ADS between January 2013 and June 2021. Three nutritional parameters were employed for analysis (PNI, anemia, and hypoalbuminemia). We utilized the Scoliosis Research Society-22 (SRS-22) questionnaire and the Oswestry Disability Index (ODI) questionnaire to assess clinical outcomes. Following the epidemiology guidelines, we presented results from three different models: the crude model, minimally adjusted model, and fully adjusted model. A total of 316 ADS patients were included in the statistical analysis. There was no significant difference in sagittal plane radiographic parameters between the two groups. After adjusting for important confounding factors, PNI was an independent predictor of postoperative HRQOL. Specifically, for each one-unit increase in PNI, there was an approximately 20% higher likelihood of patients achieving a better HRQOL. Furthermore, we did not observe an association between hemoglobin levels or albumin levels and HRQOL. In this study, PNI has been demonstrated to be correlated with the postoperative HRQOL in patients with ADS undergoing corrective surgery.

Regulatory effects of Hemin on prevention and rescue of salt stress in rapeseed (Brassica napus L.) seedlings.

BACKGROUND: Salt stress severely restricts rapeseed growth and productivity. Hemin can effectively alleviate salt stress in plants. However, the regulatory effect of Hemin on rapeseed in salt stress is unclear. Here, we analyzed the response and remediation mechanism of Hemin application to rapeseed before and after 0.6% (m salt: m soil) NaCl stress. Experiment using two Brassica napus (AACC, 2n = 38) rapeseed varieties Huayouza 158R (moderately salt-tolerant) and Huayouza 62 (strongly salt-tolerant). To explore the best optional ways to improve salt stress resistance in rapeseed. RESULTS: Our findings revealed that exogenous application of Hemin enhanced morph-physiological traits of rapeseed and significantly attenuate the inhibition of NaCl stress. Compared to Hemin (SH) treatment, Hemin (HS) significantly improved seedlings root length, seedlings height, stem diameter and accumulated more dry matter biomass under NaCl stress. Moreover, Hemin (HS) significantly improved photosynthetic efficiency, activities of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX), and decreased electrolyte leakage (EL) and malondialdehyde (MDA) content, thus resulting in the alleviation of oxidative membrane damage. Hemin (HS) showed better performance than Hemin (SH) under NaCl stress. CONCLUSION: Hemin could effectively mitigate the adverse impacts of salt stress by regulating the morph-physiological, photosynthetic and antioxidants traits of rapeseed. This study may provide a basis for Hemin to regulate cultivated rapeseed salt tolerance and explore a better way to alleviate salt stress.

The role and mechanism of inflammatory response to growing rod implantation in early onset scoliosis.

Growing rod implantation, a surgery treatment for EOS (early onset scoliosis), may cause a kind of chronic inflammation called metalosis and all other implant-related complications because of the metal debris released by the implants as a result of fraction and corrosion. There is no complete explanation of immunologic mechanisms of metalosis up to now. This review demonstrates the researches on metalosis from the clinical issues down to basic immunologic mechanisms. Adverse reactions of metal implants are mainly the formation of NLRP3 (nod-like receptor protein 3) inflammasome, primed by TLR4 (toll-like receptor protein 4), activated by phagocytosis and often accompanied by type Ⅳ hypersensitive reaction. Recent studies found that TNF-α (tumor necrosis factor α) also participates in priming, and activation of inflammasome requires disturbance of lysosome and release of cathepsin B. Ca-074Me and MCC950 are therapeutic interventions worth exploring in aseptic loosening of orthopedic implants.

Traditional Dual Growing Rods With 2 Different Apical Control Techniques in the Treatment of Early-Onset Scoliosis.

OBJECTIVE: Based on traditional dual growing rods (TDGR), apical control techniques (ACTs) were introduced as adjuvant procedures to improve deformity correction at the apex segment in the treatment of early-onset scoliosis (EOS). We aimed to explore whether TDGR+ ACTs have different indications, attain more deformity correction, have negative effects on spinal growth, and have different complications. METHODS: Between 2004 and 2019, a retrospective study of EOS patients treated with TDGR with or without ACTs was conducted and divided into 3 groups: TDGR group; hybrid technique (HT) group: Vertebrectomy/hemivertebrectomy with short fusion and TDGR; ACPS group: apical convex control pedicle screws (ACPS) and TDGR. Demographic, radiographic parameters, clinical outcomes, complications, and revisions were analyzed and compared. RESULTS: Seventy-eight EOS patients were enrolled. The preoperative main curve was the largest in the HT group. ACPS group had the smallest residual curve (19° ± 8.9°) and apical vertebral translation (12.0 ± 9.0 mm) at the latest follow-up, followed by the HT group (30° ± 17.4°, 22.1 ± 13.4 mm) and TDGR group (30° ± 13.2°, 32.8 ± 17.1 mm). ACPS group had the largest T1-12 height and T1-S1 height after index surgery. Complications and revisions in the ACTs groups was lower than the TDGR group. Scoliosis Research Society-22 self-image questionnaire was superior in the ACPS group. CONCLUSION: According to our intermediate results, TDGR+ACTs could improve correction ability of apex deformity. ACTs had little deleterious effects on spinal height during the lengthening procedures, with a lower complication rate than TDGR. TDGR+ACTs might be a supplemental option for suitable EOS patients.

Risk factors for intensive care unit admission following correction surgery for adult spinal deformity.

OBJECTIVE: The literature currently available on the characteristics of patients who require intensive care unit (ICU) admission after correction surgery for adult spinal deformity is lacking; this study aimed to identify risk factors for postoperative ICU admission following correction surgery for adult spinal deformity. METHODS: A retrospective review of patients who underwent primary posterior-based spinal fusion from 2015 to 2023 was performed. According to the ward they returned to, patients were further divided into an ICU group and a non-ICU group. Univariate and multivariate analyses were performed to evaluate preoperative and perioperative parameters to identify independent risk factors for postoperative ICU admission in adult spinal deformity patients. RESULTS: A total of 274 patients were included, including 115 males (41.97%) and 159 females (58.03%). The mean age of the patients was 32.00 ± 11.16 years (19-77 years). Following adjusted analysis, the preoperative and perioperative factors that were independently associated with ICU admission were age, body mass index ≥ 28 kg/m2, neuromuscular spinal deformity, respiratory disease, grade III-IV American Society of Anesthesiologists (ASA) classification, a scoliosis Cobb angle ≥ 90°, a kyphosis Cobb angle ≥ 90°, and ≥ 12 fused segments. Compared with the non-ICU group, the ICU group had a higher incidence of complications, a longer hospital stay, and higher medical costs (P < 0.05). CONCLUSION: This study identified independent risk factors associated with postoperative ICU admission in adult spinal deformity patients; and explored relative measures to decrease or avoid the risk of postoperative ICU admission. Surgeons could use these data to develop and plan appropriate perioperative care processes in advance and provide consultation for family members before surgery.

Combined transcriptomic and metabolomic analysis of alginate oligosaccharides alleviating salt stress in rice seedlings.

BACKGROUND: Salt stress is one of the key factors limiting rice production. Alginate oligosaccharides (AOS) enhance plant stress resistance. However, the molecular mechanism underlying salt tolerance in rice induced by AOS remains unclear. FL478, which is a salt-tolerant indica recombinant inbred line and IR29, a salt-sensitive rice cultivar, were used to comprehensively analyze the effects of AOS sprayed on leaves in terms of transcriptomic and metabolite profiles of rice seedlings under salt stress. RESULTS: In this experiment, exogenous application of AOS increased SOD, CAT and APX activities, as well as GSH and ASA levels to reduce the damage to leaf membrane, increased rice stem diameter, the number of root tips, aboveground and subterranean biomass, and improved rice salt tolerance. Comparative transcriptomic analyses showed that the regulation of AOS combined with salt treatment induced the differential expression of 305 and 1030 genes in FL478 and IR29. The expressed genes enriched in KEGG pathway analysis were associated with antioxidant levels, photosynthesis, cell wall synthesis, and signal transduction. The genes associated with light-trapping proteins and RLCK receptor cytoplasmic kinases, including CBA, LHCB, and Lhcp genes, were fregulated in response to salt stress. Treatment with AOS combined with salt induced the differential expression of 22 and 50 metabolites in FL478 and IR29. These metabolites were mainly related to the metabolism of amino and nucleotide sugars, tryptophan, histidine, and ß -alanine. The abundance of metabolites associated with antioxidant activity, such as 6-hydroxymelatonin, wedelolactone and L-histidine increased significantly. Combined transcriptomic and metabolomic analyses revealed that dehydroascorbic acid in the glutathione and ascorbic acid cycles plays a vital role in salt tolerance mediated by AOS. CONCLUSION: AOS activate signal transduction, regulate photosynthesis, cell wall formation, and multiple antioxidant pathways in response to salt stress. This study provides a molecular basis for the alleviation of salt stress-induced damage by AOS in rice.

The incidence and interrelationship of hemivertebra and concomitant cardiac abnormalities in congenital scoliosis.

BACKGROUND: Congenital scoliosis(CS) is associated with multiple organs defect, and cardiac abnormalities have been reported commonly associated with CS. Hemivertebra is caused by the failure of vertebral formation, which is a major constitute of CS. Till now, few studies focus on the incidence and interrelationship of hemivertebra and concomitant cardiac abnormalities in congenital scoliosis. We aimed to analyze the cardiac defect in CS patients with or without hemivertebra, and further explore the incidence of cardiac defect between different types of hemivertebra. METHODS: The ultrasonic cardiography (UCG) results of surgically treated congenital scoliosis (CS) patients between 2015 and 2018 were retrospectively analyzed. Patients were divided into hemivertebra group and non-hemivertebra group according to preoperative CT. Patients with hemivertebra was further divided into sub-group by single/multiple or fully/partially/mixed segmented hemivertebra. Demographic information, radiographic data and cardiac abnormalities were statistically compared between groups. RESULTS: A total of 329 patients were analyzed, including 216 patients with hemivertebra and 113 patients without hemivertebra. UCG results were abnormal in 89 cases (27.1%), including 41 males(12.5%) and 48 females(14.6%). Hemivertebra group had comparable incidence of cardiac abnormalities with non-hemivertebra group (p = 0.517). No significant difference in the incidence of UCG abnormalities between single and multiple hemivertebra group (P = 0.246). Binary logistic regression analysis showed that female sex with multiple hemivertebra was a risk factor for abnormal UCG (P = 0.009, OR = 3.449). Cardiac abnormalities was comparable among fully, partially and mixed segmented hemivertebra group(P = 0.264). In abnormal UCG, 33 patients with hemivertebra had non-valvular abnormalities, and 48.5% (16/33) were septal defects. 28 patients had valvular abnormalities, most of them were mitral valve abnormalities, especially mitral valve redundancy, prolapse and insufficiency(82.1%, 23/28). No significant difference between the incidence of non-valvular and valvular abnormalities in patients with hemivertebra (P = 0.581). CONCLUSIONS: The incidence of abnormal UCG results was approximately 28.2% in CS patients with hemivertebra. Female patients with multiple hemivertebra had a higher risk of UCG abnormalities. Mitral valve abnormalities were the most common abnormality of UCG found in CS patients with hemivertebra. TRIAL REGISTRATION: retrospectively registered.

Ten-year trends in surgical management of 1207 congenital scoliosis.

PURPOSE: To report and analyze development trends in the surgical treatment of congenital scoliosis (CS) in a large CS cohort over a 10-year period. METHODS: We retrospectively searched and extracted medical records of CS inpatients receiving posterior instrumented fusion surgery at our institute from January 2010 to December 2019. We analyzed information on demographics and surgical information, including the surgical approach, number of fused segments, use of osteotomy and titanium cage implantation, length of stay, intraoperative blood loss, and rates of complications and readmission. RESULTS: 1207 CS inpatients were included. In the past decade, the proportion of patients younger than 5 years increased from 15.5 to 26.9%. The average number of fused segments decreased from 9.24 to 7.48, and the proportion of patients treated with short-segment fusion increased from 13.4 to 30.3%. The proportion of patients treated with osteotomy and titanium cage implantation increased from 55.65% and 12.03% to 76.5% and 40.22%. The average length of stay and blood loss decreased from 16.5 days and 816.1 ml to 13.5 days and 501.7 ml. The complication and readmission rates also decreased during these ten years. CONCLUSION: During this ten-year period, the surgical treatment of CS at our institute showed trends toward a younger age at fusion, lower number of fused segments, higher rate of osteotomy and titanium cage implantation, reduced blood loss, shorter length of stay and lower rate complications and readmission. These results suggest performing osteotomy combined with titanium cage implantation at an earlier age can achieve fewer fused segments and complications.

Dual Growing Rods Combined With the Apical Convex Control Pedicle Screw Technique Versus Traditional Dual Growing Rods for the Surgical Treatment of Early-Onset Scoliosis: A Case-Matched 2-Year Study.

BACKGROUND: Combination of apical control convex pedicle screws (ACPS) with traditional dual growing rods (TDGRs) had better apex control ability for early-onset scoliosis (EOS); however, there is a paucity of studies on the ACPS technique. OBJECTIVE: To compare 3-dimensional deformity correction parameters and complications between the apical control technique (DGR + ACPS) and TDGR in the treatment of EOS. METHODS: A retrospective case-match analysis consisting of 12 cases of EOS treated with the DGR + ACPS technique (group A) from 2010 to 2020, and matched with TDGR case (group B) at a ratio of 1:1 by age, sex, curve type, major curve degree, and apical vertebral translation (AVT). Clinical assessment and radiological parameters were measured and compared. RESULTS: Demographic characteristics, preoperative main curve, and AVT were comparable between groups. The correction ability of the main curve, AVT, and apex vertebral rotation were better in group A at index surgery ( P < .05). The increase in T1-S1 and T1-T12 height was large in group A at index surgery ( P = .011, P = .074). The annual increase in spinal height was slower in group A, but without significant difference. The surgical time and estimated blood loss were comparable. Six complications occurred in group A, and 10 occurred in group B. CONCLUSION: In this preliminary study, ACPS seems to provide better correction of apex deformity, while attaining the comparable spinal height at 2-year follow-up. Larger cases and longer follow-up are needed to achieve reproducible and optimal results.

Correlation between supine flexibility and postoperative correction in adolescent idiopathic scoliosis.

BACKGROUND: The preoperative flexibility of the scoliotic spine is a key aspect of surgical planning, as it provides information on the rigidity of the curve, the extent of structural changes, the levels to be fused and the amount of correction. The purpose of this study was to assess whether supine flexibility can be used to predict postoperative correction in patients with adolescent idiopathic scoliosis (AIS) by determining the correlation between these two characteristics. METHODS: A total of 41 AIS patients who underwent surgical treatment between 2018 and 2020 were retrospectively enrolled for analysis. Preoperative and postoperative standing radiographs and preoperative CT images of the entire spine were collected and used to measure supine flexibility and the postoperative correction rate. T tests were used to analyse the differences in supine flexibility and postoperative correction rate between groups. Pearson's product-moment correlation analysis was performed, and regression models were established to determine the correlation between supine flexibility and postoperative correction. Thoracic curves and lumbar curves were analysed independently. RESULTS: Supine flexibility was found to be significantly lower than the correction rate but showed a strong correlation with the postoperative correction rate, with r values of 0.68 for the thoracic curve group and 0.76 for the lumbar curve group. The relationship between supine flexibility and postoperative correction rate could be expressed by linear regression models. CONCLUSION: Supine flexibility can be used to predict postoperative correction in AIS patients. In clinical practice, supine radiographs may be used in place of existing flexibility test techniques.

Clinical outcomes of the traditional dual growing rod technique combined with apical pedicle screws in the treatment of early-onset scoliosis: preliminary results from a single center.

OBJECTIVE: Limited control of an apical deformity is a major disadvantage in the traditional dual growing rod (TDGR) technique. Previous literature has reported the results of apical pedicle screw placement (APS) as an apical control technique in patients with early-onset scoliosis (EOS). However, the clinical outcomes, indications, and complications of the TDGR technique combined with APSs have not been well described. The purpose of this study was to evaluate the preliminary clinical outcomes of the TDGR technique combined with APSs in EOS patients. METHODS: Clinical data of 12 patients with EOS who were treated with the TDGR technique combined with APSs at the index surgery at the authors' center from January 2010 to January 2020, with a minimum 2-year follow-up, were retrospectively reviewed. Indications for the use of APSs included 1) no vertebral segmentation failure, fused ribs, or multiple hemivertebrae at the apex; 2) at least 2 normal discs around the apex; and 3) proper development of apical pedicles on the convex side. Etiology, age at index surgery, number of lengthening procedures, follow-up duration, and complications were recorded. Radiographic measurements included Cobb angle, apical vertebral translation (AVT), apical vertebral rotation (AVR), thoracic kyphosis, lumbar lordosis, spine height, and space available for the lung (SAL). RESULTS: The mean follow-up period was 4.0 ± 1.4 years, with a mean of 4.8 lengthening procedures per patient. The mean Cobb angle improved from 61.7° ± 10.4° to 19.9° ± 9.0° after the index surgery (19.6° ± 9.4° at the latest follow-up). The mean postindex AVT decreased to 16.8 ± 8.9 mm from a preindex AVT of 56.3 ± 9.7 mm and further improved to 13.6 ± 10.0 mm at the latest follow-up. The mean annual increases in T1-12 and T1-S1 height were 9.0 ± 4.7 mm and 13.9 ± 6.5 mm, respectively. The SAL improved from 0.91 to 1.04 at the latest follow-up. AVR improved significantly after the index surgery (p = 0.013), while minor deterioration was observed after repeat lengthening procedures. Five complications (2 implant related and 3 alignment related) occurred in 4 patients. CONCLUSIONS: For EOS patients with good flexibility (without segmentation failure or multiple hemivertebrae at the apex), the TDGR technique combined with APSs can improve primary curve correction, maintain good correction results, and allow continuous spine growth, which may reduce the risks of complications during lengthening treatment. More multicenter prospective studies with larger samples are needed to further validate the findings of this study.

Enhanced Room-Temperature Thermoelectric Performance of 2D-SnSe Alloys via Electric-Current-Assisted Sintering.

Single-crystalline tin-selenide (SnSe) has emerged as a high-performance and eco-friendly alternative to the lead-chalcogens often used in mid-temperature thermoelectric (TE) generators. At high temperature >800 K, the phase transition from Pnma to Cmcm causes a significant rise in the TE figure-of-merit (zT) curve. Conversely, the SnSe TE requires a booster at low temperatures, which allows broader applicability from a device perspective. Herein, a synergy of Cu alloy and Ag-coating is realized through a sequential multi-step synthesis, designed to combine different metal deposition effects. Single-crystalline (Cu2Se)x(SnSe)1−x alloys grown by the Bridgman method were then coated with a thin Ag layer by radio frequency (RF) sputtering, and the interlayer epitaxial film was observed via electric-current assisted sintering (ECAS). Consequently, the thin Ag-coating improves the electrical conductivity (σ) and reduces the thermal conductivity (κ) for (Cu2Se)0.005(SnSe)0.995+Ag alloy, increasing the zT curve at close to room temperature (373 K). The incorporation of multistep addition by ECAS enables tuning of the overall solubility of the alloy, which opens a new avenue to optimize TE performance in anisotropic 2D materials.

Hybrid technique versus traditional dual growing rod technique to treat congenital early-onset scoliosis: a comparative study with more than 3 years of follow-up.

OBJECTIVE: The authors' objective was to compare the intermediate outcomes of patients with severe congenital early-onset scoliosis (CEOS) treated with posterior vertebrectomy/hemivertebrectomy with short fusion and dual growing rods (hybrid technique [HT]) and those treated with traditional dual growing rods (TDGRs). METHODS: A retrospective study of patients who underwent the HT and TDGR technique for CEOS was conducted. The inclusion criteria were CEOS (age < 10 years), Risser stage 0, treatment with HT or TDGR, index surgery performed between 2004 and 2017, and minimum follow-up of 3 years. For patients who completed lengthening procedures, the last lengthening procedure was considered the latest follow-up. Demographic, radiographic, clinical, and patient-reported outcomes and revisions were compared between groups. RESULTS: Sixty-one patients with CEOS were included in this study, with 16 treated with HT and 45 with TDGR technique. There were no differences in age at index surgery, duration of treatment, or number of lengthening procedures. The lengthening interval was longer in the HT group. The preoperative mean ± SD main curve was 81.8° ± 17.1° for the HT group and 63.3° ± 16.9° for the TDGR group (p < 0.05). However, main curve correction was better in the HT group, and no differences in residual curve were found between groups. Although the preoperative apex vertebral translation (AVT) of the HT group was greater, the correction of AVT was better in the HT group (p < 0.05). No differences in T1-S1 and T1-12 height were found between groups at the latest follow-up. The growth of T1-S1 height was less in the HT group (p < 0.05), whereas the growth of T1-12 height was similar between groups. Patients in the HT group had a lower risk of mechanical complications but higher risks of dural tears and neurological complications. CONCLUSIONS: HT may provide better correction and apex control ability than TDGR for EOS patients with severe and rigid deformity at the apex level, and it significantly decreased the risk of mechanical complications with little influence on growth of the thoracic spine. HT may be an option for patients with severe CEOS with large asymmetrical growth potential around the apex of the curve.

Lowest Instrumented Vertebra at L3 Versus L4 in Posterior Fusion for Moderate Lenke 5C Type Adolescent Idiopathic Scoliosis: A Case-Match Radiological Study.

OBJECTIVE: To compare the radiological outcomes in Lenke 5C type patients whose lowest instrumented vertebra (LIV) was L3 or L4 in a case-match study. METHODS: We conducted a retrospective case-match study and included 82 patients in the study. Radiological results before surgery, after surgery, and at last follow-up were recorded and analyzed in the L3 and L4 groups. RESULTS: After matching the age, Risser's sign, sex, and main Cobb, 41 pairs of patients were enrolled in our study. The total fusion segments in the L3 group (median [interquartile range]: 5.0 [6.0-5.0]) were shorter than those in the L4 group (6.0 [6.5-6.0]). The main curve was significantly corrected after surgery in both groups, and was comparable at the last followup between groups. In addition, according to the results of Fisher precision probability test, there was no significant difference of coronal or sagittal imbalance between the 2 groups at the 2-year follow-up. CONCLUSION: The correction in coronal and sagittal planes in L3 group and L4 group remains similar. On account of more motion segments, L3 could be an ideal choice as LIV in moderate Lenke 5C type AIS. Long-term follow-up is needed to evaluate the effect of larger compensatory lumbar-sacral curve when stopping at L3.