Does Combining Drilling and Curettage to Percutaneous Trans-epiphyseal Screws Improve Correction of Limb Length Discrepancy? A Comparative Study.

Objectives: Physeal drilling and curettage (PDC) and percutaneous epiphysiodesis using transphyseal screws (PETS) are among the most widely used techniques to treat leg-length discrepancy (LLD). This study compared the efficacy and outcomes between PETS alone and PETS combined with PDC (PETS + PDC). Methods: Retrospective study of children who underwent epiphysiodesis of the proximal tibia or distal femur with either PETS or PETS + PDC between 2008 and 2018 at a single institution. Radiographic parameters and complications were reviewed at completion of treatment and most recent follow-up. Results: A total of 23 epiphysiodeses in 15 patients, average age 13.1 years, with either PETS (13 femur/tibias) or PETS + PDC (10 femur/tibias) were included. PETS patients were treated for a longer time (median: 24 months vs 11 months, p = 0.004), however, follow-up time was similar between groups (p = 0.577), on average 2.7 years. In the PETS group, LLD decreased from 2.55 to 0.84 cm at most recent follow-up (p = 0.010), and in the PETS + PDC group from 3.01 to 1.2 cm (p = 0.005), achieving a correction of 1.71 cm for PETS and 1.83 cm for PETS + PDC (p = 0.871). A correction of LLD to ≤ 2 cm was achieved in 8 PETS (89%) and 4 PETS + PDC cases (67%) (p = 0.525). Two PETS patients (22%) and 1 PETS + PDC (17%) patient returned to the OR for further correction due to persistent LLD (p = 1.000). No differences existed in total number of complications, angular deformity or return to physical activity between groups (p ≥ 0.05 for each comparison). Conclusions: This study showed equal efficiency in resolving LLD between the PETS and PETS + PDC procedures with minimal operative complications.Level of Evidence III.

The complex treatment paradigms for concomitant tethered cord and scoliosis: illustrative case.

BACKGROUND: Scoliosis associated with tethered cord syndrome is one of the most challenging spinal deformities to manage. Multiple surgical approaches have been developed, including traditional staged and concomitant procedures, spine-shortening osteotomies, and individual vertebral column resections. OBSERVATIONS: A 10-year-old female presented with congenital kyphoscoliosis with worsening curve progression, tethered spinal cord, and a history of enuresis. The scoliosis had progressed to a 26° coronal curve and 55° thoracolumbar kyphosis. Preoperative magnetic resonance imaging of the spine revealed a tethered cord between the levels of L3-4 and a large kyphotic deformity at L1. The patient underwent laminectomy, during which intraoperative motor signals were lost. A planned hemivertebrectomy at L1 was performed prior to an L4 laminectomy, untethering of the filum terminale, and posterior spinal fusion from T11 to L2. After surgery, the patient experienced transient lower-extremity weakness, with her neurological function improving from baseline over the next 2 months. Ultimately, the goal of this surgery was to halt the progressive decline in motor function, which was successfully achieved. LESSONS: Much remains to be learned about the treatment of this complicated disease, especially in the setting of concomitant scoliosis. This case serves to exemplify the complex treatment paradigms that exist when attempting to manage this clinical syndrome and that more remains to be learned.

Analysis of ANRIL Isoforms and Key Genes in Patients with Severe Coronary Artery Disease.

ANRIL (Antisense Noncoding RNA in the INK4 Locus), also named CDKN2B-AS1, is a long non-coding RNA with outstanding functions that regulates genes involved in atherosclerosis development. ANRIL genotypes and the expression of linear and circular isoforms have been associated with coronary artery disease (CAD). The CDKN2A and the CDKN2B genes at the CDKN2A/B locus encode the Cyclin-Dependent Kinase inhibitor protein (CDKI) p16INK4a and the p53 regulatory protein p14ARF, which are involved in cell cycle regulation, aging, senescence, and apoptosis. Abnormal ANRIL expression regulates vascular endothelial growth factor (VEGF) gene expression, and upregulated Vascular Endothelial Growth Factor (VEGF) promotes angiogenesis by activating the NF-κB signaling pathway. Here, we explored associations between determinations of the linear, circular, and linear-to-circular ANRIL gene expression ratio, CDKN2A, VEGF and its receptor kinase insert domain-containing receptor (KDR) and cardiovascular risk factors and all-cause mortality in high-risk coronary patients before they undergo coronary artery bypass grafting surgery (CABG). We found that the expression of ANRIL isoforms may help in the prediction of CAD outcomes. Linear isoforms were correlated with a worse cardiovascular risk profile while the expression of circular isoforms of ANRIL correlated with a decrease in oxidative stress. However, the determination of the linear versus circular ratio of ANRIL did not report additional information to that determined by the evaluation of individual isoforms. Although the expressions of the VEFG and KDR genes correlated with a decrease in oxidative stress, in binary logistic regression analysis it was observed that only the expression of linear isoforms of ANRIL and VEGF significantly contributed to the prediction of the number of surgical revascularizations.

The Impact of Standardized Recovery Pathways on Language Barriers and Inpatient Pain Management.

BACKGROUND AND OBJECTIVES: Inpatient postoperative care is reliant upon clear, open communication between providers and patient-families, and thus is particularly vulnerable to disparities when discordant languages exist. It is not yet understood how standardized postoperative protocols may mitigate disparities related to language discordance. METHODS: This is a retrospective cohort study among adolescent idiopathic scoliosis patients who underwent posterior spinal fusion at a tertiary care children's hospital in Bronx, New York after implementation of a postoperative pathway in 2017. Outcomes reliant upon communication between patient-families and providers were measured, including measures of pain management (number and type of pain medications requested, daily pain assessments, total opioids consumed), as well as outpatient pain scores. RESULTS: A total of 160 patients were included (39 language other than English [LOE]). Between patient cohorts, there were no significant differences in demographic or operative characteristics. On univariate analyses, LOE patients were more likely to be given a basal dosing of patient-controlled analgesia or additional boluses (26% vs 12%, P = .03), consumed 0.53 fewer benzodiazepine medications per day (P = .01), and were more likely to have pain at outpatient follow-up (67% vs 43%, P = .03). On multivariate analyses, LOE patients were more likely to be placed on basally dosed or receive additional boluses of patient-controlled analgesia (odds ratio 3.19, 95% confidence interval 1.15-8.85). CONCLUSIONS: As standardized pathways become more common in health care, it is critical to monitor for components of these protocols that may be vulnerable to language-related disparities, such as therapies reliant on symptom description and outpatient follow-up.

Consensus-Based Best Practice Guidelines for the Management of Spinal Deformity and Associated Tumors in Pediatric Neurofibromatosis Type 1: Screening and Surveillance, Surgical Intervention, and Medical Therapy.

BACKGROUND: Spinal conditions, such as scoliosis and spinal tumors, are prevalent in neurofibromatosis type 1 (NF1). Despite the recognized importance of their early detection and treatment, there remain knowledge gaps in how to approach these manifestations. The purpose of this study was to utilize the experience of a multidisciplinary committee of experts to establish consensus-based best practice guidelines (BPGs) for spinal screening and surveillance, surgical intervention, and medical therapy in pediatric patients with NF1. METHODS: Using the results of a prior systematic review, 10 key questions that required further assessment were first identified. A committee of 20 experts across medical specialties was then chosen based on their clinical experience with spinal deformity and tumors in NF1. These were 9 orthopaedic surgeons, 4 neuro-oncologists/oncologists, 3 neurosurgeons, 2 neurologists, 1 pulmonologist, and 1 clinical geneticist. An initial online survey on current practices and opinions was conducted, followed by 2 additional surveys via a formal consensus-based modified Delphi method. The final survey involved voting on agreement or disagreement with 35 recommendations. Items reaching consensus (≥70% agreement or disagreement) were included in the final BPGs. RESULTS: Consensus was reached for 30 total recommendations on the management of spinal deformity and tumors in NF1. These were 11 recommendations on screening and surveillance, 16 on surgical intervention, and 3 on medical therapy. Five recommendations did not achieve consensus and were excluded from the BPGs. CONCLUSION: We present a set of consensus-based BPGs comprised of 30 recommendations for spinal screening and surveillance, surgical intervention, and medical therapy in pediatric NF1.

Percutaneous epiphysiodesis using transphyseal screws (PETS) versus tension-band plating (TBP): comparative study of outcomes for correcting limb length discrepancy.

OBJECTIVES: The best effective treatment strategy for limb length discrepancy (LLD) is still being debated. The goal of this study was to compare the efficacy and results of tension-band plating (TBP) and percutaneous epiphysiodesis using transphyseal screws (PETS) for LLD correction. METHODS: From June 2008 to January 2019, children who had lower extremity epiphysiodesis with either TBP or PETS were reviewed retrospectively. At the conclusion of treatment, LLD, angular deformity, and complications were reviewed. The t-test or Wilcoxon rank sum test was used to compare continuous variables. Categorical variables were evaluated using Fisher's exact test or χ2 test. RESULTS: A total of 32 epiphysiodeses with TBP (14 patients, 24 femur/tibias) or PETS (13 patients, 23 femur/tibias) were compared. TBPs were conducted while the patients were younger (11.0 vs. 13.1 years, p = 0.005). The treatment durations were similar in both groups (TBP: 23.5 months vs. PETS: 24 months, p = 0.132). PETS had significantly shorter operative time (p = 0.047), length of hospital stay (p = 0.014), and time to return to full activity (p = 0.043). LLD in the TBP group reduced from 2.64 to 1.38 cm (p = 0.005), while in the PETS group it decreased from 2.76 to 1.08 cm (p = 0.001). During treatment, the rate of LLD correction was 0.49 ± 0.9 cm/year for limbs treated with TBP and 1.0 ± 1.1 cm/year for limbs treated with PETS (p = 0.185). At the end of treatment, 8 TBP cases (47%) and 9 PETS cases (60%) had achieved LLD ≤ 2 cm (p = 0.502), and at the most recent follow-up, this had grown to 11 (65%) in the TBP group and 12 (80%) in the PETS group. There were no significant differences in the total number of complications between groups (p > 0.05). Revision surgery was required in 11 TBP and 3 PETS limbs due to persistent LLD or angular deformity (AD) (p = 0.016). Logistic regression did not reveal any significant association between TBP and the rate of complication or revision surgery. CONCLUSION: PETS and TBP are both effective methods for limb length equalization. PETS, on the other hand, was linked to a shorter operative time, a shorter hospital stay, a faster recovery to pre-operative function, and a lower complication rate. The rate of revision surgery due to persistent LLD or AD was higher in TBP. We advise surgeons against utilizing TBP to correct LLD. LEVEL OF EVIDENCE: III.

Cigarette smoking and complications in elective thoracolumbar fusions surgery: An analysis of 58,304 procedures.

Study Design: This was retrospective cohort study. Purpose: The current investigation uses a large, multi-institutional dataset to compare short-term morbidity and mortality rates between current smokers and nonsmokers undergoing thoracolumbar fusion surgery. Overview of Literature: The few studies that have addressed perioperative complications following thoracolumbar fusion surgeries are each derived from small cohorts from single institutions. Materials and Methods: A retrospective study was conducted on thoracolumbar fusion patients in the American College of Surgeons National Surgical Quality Improvement Program database (2006-2016). The primary outcome compared the rates of overall morbidity, severe postoperative morbidity, infections, pneumonia, deep venous thrombosis (DVT), pulmonary embolism (PE), transfusions, and mortality in smokers and nonsmokers. Results: A total of 57,677 patients were identified. 45,952 (78.8%) were nonsmokers and 12,352 (21.2%) smoked within 1 year of surgery. Smokers had fewer severe complications (1.6% vs. 2.0%, P = 0.014) and decreased discharge to skilled nursing facilities (6.3% vs. 11.5%, P < 0.001) compared to nonsmokers. They had lower incidences of transfusions (odds ratio [OR] = 0.9, confidence interval [CI] = 0.8-1.0, P = 0.009) and DVT (OR = 0.7, CI = 0.5-0.9, P = 0.039) as well as shorter length of stay (LOS) (OR = 0.9, CI = 0.9-0.99, P < 0.001). They had a higher incidence of postoperative pneumonia (OR = 1.4, CI = 1.1-1.8, P = 0.002). There was no difference in the remaining primary outcomes between smoking and nonsmoking cohorts. Conclusions: There is a positive correlation between smoking and postoperative pneumonia after thoracolumbar fusion. The incidence of blood transfusions, DVT, and LOS was decreased in smokers. Early postoperative mortality, severe complications, discharge to subacute rehabilitation facilities, extubation failure, PE, SSI, and return to OR were not associated with smoking.

Pre-operative prone radiographs can reliably determine spinal curve flexibility in adolescent idiopathic scoliosis (AIS).

PURPOSE: The purpose of this study was to evaluate the correlation between non-effort prone and bending radiographs in determining curve flexibility in adolescent idiopathic scoliosis (AIS). METHODS: A retrospective review of AIS patients who underwent pre-operative full spine radiographic imaging from 2006 to 2019 was performed. The Cobb angle (CA) of proximal thoracic (PT), main thoracic (MT) and thoracolumbar/lumbar (TL/L) curves were measured and correlated on standing, prone and bending radiographs. Standing, bending, and prone measurements were correlated using Spearman's analysis, and intra-rater reliability was evaluated using intraclass correlation analysis. RESULTS: A total of 381 patients (74% female) with a mean age of 15.1 ± 2.5 years were identified. A strong correlation existed between the prone and bending CA for the PT (rs = 0.797, p < 0.01) and MT (rs = 0.779, p < 0.01) curve and a moderate correlation existed between the prone and bending TL/L curve (rs = 0.641, p < 0.01). For a non-structural PT curve, a prone CA < 25° correctly identified a bending CA < 25° 96.7% of the time (p < 0.005). For a non-structural MT curve, a prone CA < 35° correctly identified a bending CA < 25° 90.2% of the time (p < 0.005). For a non-structural TL/L curve, a prone CA < 35° correctly identified a bending CA < 25° 95% of the time (p < 0.005). CONCLUSION: Prone radiographs demonstrated a moderate to strong correlation with bending radiographs and may be used as a proxy for determining spinal flexibility, especially when bending films are deemed unreliable. LEVEL OF EVIDENCE: III.

Posterior-only Resection of Single Hemivertebrae With 2-Level Versus >2-Level Fusion: Can We Improve Outcomes?

BACKGROUND: The outcomes of congenital scoliosis (CS) patients undergoing hemivertebra (HV) resection surgery with a 2-level fusion versus a >2-level fusion are unclear. We hypothesized that CS patients undergoing HV resection and a >2-level fusion have decreased curve progression and reoperation rates compared with 2-level fusions. METHODS: Retrospective review of prospectively collected data from a multicenter scoliosis database. Fifty-three CS patients (average age 4.5, range 1.2 to 10.9 y) at index surgery were included. Radiographic and surgical parameters, complications, as well as revision surgery rates were tracked at a minimum of 2-year follow-up. RESULTS: Twenty-six patients had a 2-level fusion while 27 patients had a >2-level fusion with similar age and body mass index between groups. The HV was located in the lumbar spine for 69% (18/26) 2-level fusions and 30% (8/27) >2-level fusions ( P =0.006). Segmental HV scoliosis curve was smaller in 2-level fusions compared to >2-level fusions preoperatively (38 vs. 50 degrees, P =0.016) and at follow-up (25 vs. 34 degrees, P =0.038). Preoperative T2-T12 (28 vs. 41 degrees, P =0.013) and segmental kyphosis (11 vs. 23 degrees, P =0.046) were smaller in 2-level fusions, but did not differ significantly at postoperative follow-up (32 vs. 39 degrees, P =0.22; 13 vs. 11 degrees, P =0.64, respectively). Furthermore, the 2 groups did not significantly differ in terms of surgical complications (27% vs. 22%, P =0.69; 2-level fusion vs. >2-level fusion, respectively), unplanned revision surgery rate (23% vs. 22%, 0.94), growing rod placement or extension of spinal fusion (15% vs. 15%, P =0.95), or health-related quality of life per the EOS-Questionnaire 24 (EOSQ-24). Comparison of patients with or without the need for growing rod placement or posterior spinal fusion revealed no significant differences in all parameters analyzed. CONCLUSIONS: Two-level and >2-level fusions can control congenital curves successfully. No differences existed in curve correction, proximal junctional kyphosis or complications between short and long-level fusion after HV resection. Both short and long level fusions are viable options and generate similar risk of revision. The decision should be individualized by patient and surgeon.

Clinical relevance of circulating angiogenic cells in patients with ischemic stroke.

BACKGROUND: Endothelial progenitor cells (EPCs) are circulating angiogenic cells with endothelial features associated with risk for stroke. We aimed to delve into their functional characteristics. EPCs were isolated and cultured from Ischemic Stroke (IS) patients and predictors of their variance evaluated. METHODS: This is a single-center observational study evaluating 187 consecutively hospitalized patients with IS. EPCs were isolated from blood samples. The number of circulating angiogenic cells (CACs), colony-forming units (CFU-ECs) and the emergence of late outgrowths endothelial cells (LOECs) were counted. We collected clinical variables and measured the stromal cell-derived factor 1 alpha (SDF1α) serum levels. We also examined the relative telomere length and the expression of osteogenic gene markers in CACs. RESULTS: CACs counts and CFU-ECs colony numbers were positively correlated (rho = 0.41, p < 0.001, n = 187). We found significant differences according to whether thrombolytic treatment was performed in the distribution of CFU-ECs (odds ratio (OR) = 2.5; 95% confidence interval (CI) 1.01-6.35; p = 0.042) and CACs (OR = 4.45; 95% IC 1.2-15.5; p = 0.012). The main determinants of CACs variation were the number of risks factors, thrombolysis treatment, arterial hypertension, LOECs occurrence, and the vascular endothelial growth factor expression, whereas CFU-ECs variations depended on hemoglobin content and the relative reduction in the National Institutes of Health Stroke Scale (NIHSS) criteria. The main predictors of LOECs appearance were thrombolysis and length of hospital stay. CONCLUSIONS: Our study supports the relevance of patient risk factors and treatments in the analysis of the functional properties of EPCs.

Magnetically Controlled Growing Rods (MCGR) Versus Single Posterior Spinal Fusion (PSF) Versus Vertebral Body Tether (VBT) in Older Early Onset Scoliosis (EOS) Patients: How Do Early Outcomes Compare?

STUDY DESIGN: Retrospective review of prospective data from multicenter registry. OBJECTIVE: Compare outcomes of posterior spinal fusion (PSF) versus magnetically controlled growing rods (MCGR) versus vertebral body tethers (VBT) in 8- to 11-year-old idiopathic early onset scoliosis (EOS) patients. SUMMARY OF BACKGROUND DATA: In EOS, it is unclear at what age the benefit of growth-sparing strategies outweighs increased risks of surgical complications, compared with PSF. METHODS: One hundred thirty idiopathic EOS patients, 81% female, aged 8-11 at index surgery (mean 10.5 yrs), underwent PSF, MCGR, or VBT. Scoliosis curve, kyphosis, thoracic and spinal height, complications, and Quality of Life (QoL) were assessed preoperatively and at most recent follow-up (prior to final fusion for VBT/MCGR). RESULTS: Of 130 patients, 28.5% received VBT, 39.2% MCGR, and 32.3% PSF. The VBT cohort included more females (P < 0.0005), was older (P < 0.0005), more skeletally mature (P < 0.0005), and had smaller major curves (P < 0.0005). At follow-up, scoliosis curve corrected 41.1 ±â€Š22.4% in VBT, 52.2 ±â€Š19.9% in PSF, and 27.4 ±â€Š23.9% in MCGR (P < 0.0005), however, not all VBT/MCGR patients finished treatment. Fifteen complications occurred in 10 VBTs, 6 requiring unplanned surgeries; 45 complications occurred in 31 MCGRs, 11 requiring unplanned surgeries, and 9 complications occurred in 6 PSFs, 3 requiring unplanned revisions. Cox proportional hazards regression adjusted for age, gender, and preoperative scoliosis curve revealed that MCGR (hazard ratio [HR] = 21.0, 95% C.I. 4.8-92.5; P < 0.001) and VBT (HR = 7.1, 95% C.I. 1.4-36.4; P = 0.019) patients were at increased hazard of requiring revision, but only MCGR patients (HR = 5.6, 95% C.I. 1.1-28.4; P = 0.038) were at an increased hazard for unplanned revisions compared with PSF. Thoracic and spinal height increased in all groups. QoL improved in VBT and PSF patients, but not in MCGR patients. CONCLUSION: In older idiopathic EOS patients, MCGR, PSF, and VBT controlled curves effectively and increased spinal height. However, VBT and PSF have a lower hazard for an unplanned revision and improved QoL.Level of Evidence: 3.

Similar Adaptations to 10 Weeks Concurrent Training on Metabolic Markers and Physical Performance in Young, Adult, and Older Adult Women.

It has been proposed that the combination of high-intensity aerobic exercises and resistance training (RT) known as concurrent training (CT) could improve metabolic syndrome (MetS) markers, and that the exercise mixture in CT could dampen muscle anaerobic pathways, a result known as the interference effect. However, there is scarce evidence on its effects in women across different ages. Therefore, we sought to determine the effects of a 10-week CT intervention on MetS markers and endurance performance in adult women and compared age-related differences between young, adult, and older participants. A total of 112 women with >1 MetS risk factors were included in the study. Participants were allocated to different groups according to the following cutoff age ranges: 20-29years (y), n = 25; 30-39y, n = 35; 40-49y, n = 43; and 50-59y, n = 53. Participants performed 10 weeks of CT, including resistance training (RT), involving six major muscle groups, and high-intensity interval training (HIIT) in a cycle ergometer. Anthropometric, cardiovascular, metabolic, and performance outcomes were assessed before and after the intervention. The CT induced significant improvements in waist circumference (WC) (20-29y: -2.5; 30-39y: -4.1; 40-49y: -4.2; 50-59y: -2.8 Δcm) and the distance achieved in the six-minute walking test (6Mwt) (20-29y: +47.6; 30-39y: +66.0; 40-49y: +43.0; 50-59y: +58.6 Δm) across all age groups, without significant differences between groups. In addition, a significant correlation was found between 6Mwt and WC, independent of age. In conclusion, our results showed that a 10-week CT intervention improved MetS risk factors in women, suggesting that the beneficial effects promoted by CT are independent of age and confirming CT as an effective, age-independent training regimen to improve metabolic health in women.

How low can you go? Implant density in posterior spinal fusion converted from growing constructs for early onset scoliosis.

STUDY DESIGN: Retrospective, multicenter comparative. OBJECTIVES: Our purpose was to compare early onset scoliosis (EOS) patients treated with ultra-low, low, and high implant density constructs when undergoing conversion to definitive fusion. Larson et al. demonstrated that implant density (ID) at fusion does not correlate with outcomes in the treatment of adolescent idiopathic scoliosis, but did not address growth-friendly graduates. METHODS: EOS patients treated with growth-friendly constructs converted to fusion between 2000 and 2017 were reviewed from a multicenter database. ID was defined as number of pedicle screws, hooks, and sublaminar/bands per level fused. Patients were divided into ultra-low ID (< 1.3), low (≥ 1.3 and < 1.6), and high ID (≥ 1.6). EXCLUSION CRITERIA: < 2 years follow-up from fusion or inadequate radiographs. RESULTS: A total of 152 patients met inclusion criteria with 39 (26%) patients in the high ID group, 33 (22%) patients in the low ID group, and 80 (52%) in the ultra-low ID group. Groups were similar in operative time (p = 0.61), pre-fusion major curve (p = 0.71), mean number of levels fused (p = 0.58), clinical follow-up (p = 0.30), and radiographic follow-up (p = 0.90). Patients in the low ID group (11.6 ± 1.5 years) were slightly younger at the time of definitive fusion than patients in the ultra-low ID group (12.9 ± 2.2 years) and high ID group (12.5 ± 1.7 years) (p = 0.009). There was significantly more blood loss in the high ID group than the other two groups (high ID: 946.8 ± 606.0 mL vs. low ID: 733.9 ± 434.5 mL and ultra-low ID: 617.4 ± 517.2 mL; p = 0.01), but there was no significant difference with regard to percent of total blood volume lost (high ID: 59.3 ± 48.7% vs. low ID: 54.5 ± 37.5% vs. ultra-low ID: 51.7 ± 54.9%; p = 0.78). There was a difference in initial improvement in major curve between the groups (high ID: 21.6° vs. low ID: 18.0° vs. ultra-low ID: 12.6°; p = 0.01). However, during post-fusion follow-up, correction decreased 7.1° in the high ID group, 2.6 in the low ID group, and 2.8 in the ultra-low ID group (p = 0.19). At final follow-up, major curve correction from pre-fusion was similar between groups (high ID: 14.5° vs. low ID: 15.5° vs. ultra-low ID: 9.7°, p = 0.14). At final follow-up, there was no difference in T1-T12 length gain (p = 0.85), T1-S1 length gain (p = 0.68), coronal balance (p = 0.56), or sagittal balance (p = 0.71). The revision rate was significantly higher in the ultra-low ID group (13.8%; 11/80) versus the high ID group (2/39; 5.1%) and low ID group (0/33; 0%) (p = 0.04). CONCLUSIONS: Although an ID < 1.3 in growth-friendly graduates produces similar outcomes with regard to curve correction and spinal length gain as low and high ID, this study suggests that an ID < 1.3 is associated with an increased revision rate. LEVEL OF EVIDENCE: III.

Sagittal spinopelvic changes after posterior spinal fusion in adolescent idiopathic scoliosis.

PURPOSE: This article examines if longer posterior spinal fusions with instrumentation (PSFI) into the lumbar spine (L3/4) alter spinopelvic parameters compared with selective fusions to T12/L1/L2 in adolescent idiopathic scoliosis (AIS) patients. METHODS: We analysed radiographs of 84 AIS patients, 58 (69%) females and 26 (31%) males, who underwent PSFI at an mean age of 15 years ± 2.5 years, range 10 years to 21 years, between 1st January 2007 and 31st December 2014. Radiographic parameters were measured pre- and post-operatively at most recent follow-up (range 2 years to 8.2 years): pelvic incidence (PI), lumbar lordosis (LL, L1-S1 and L4-S1), sagittal vertical alignment (SVA), scoliosis angle and proximal junctional kyphosis (PJK). PI-LL was calculated. Data was analysed using t-tests or Wilcoxon rank-sum tests. RESULTS: In total, 32 patients underwent a selective fusion with lowest instrumented vertebra (LIV) T12-L2, and 52 patients underwent a fusion with LIV L3-L4. In both groups, scoliosis angle was significantly corrected at follow-up (p < 0.005).Pre-operatively, both groups had similar LL (L1-S1) and PI-LL. Post-operatively, LL increased in the L3-4 fusion group (p < 0.005) but did not change in the selective fusion group (p = 0.116). This change in LL in the L3-4 fusion group affected the post-operative PI-LL (T12-L2 fusion -4.9° versus L3-4 fusion -13.6°, p = 0.002). No differences were seen in PI, SVA or LL L4-S1 between groups. Radiographic PJK occurred in seven of the L3-4 patients with and without PJK (noPJK -8.8° versus PJK -25.8°, p = 0.026). CONCLUSIONS: In patients who underwent a fusion ending at L3 or L4, LL was increased. This altered the PI-LL relationship, and appeared to increase the risk of PJK. LEVEL OF EVIDENCE: III.

Fitness cardiorrespiratorio estimado mediante ecuación y su caracterización sociodemográfica en población chilena: Resultados de la Encuesta Nacional de Salud 2016-2017

Background: Cardiorespiratory fitness is a strong predictor of mortality and chronic diseases. However, its estimation is costly and time consuming which may limit it broad use in population-based studies. Aim: To estimate the cardiorespiratory fitness of the Chilean population by using equations and to characterize fitness levels of the Chilean population by sociodemographic factors. Material and Methods: This cross-sectional study included 5,958 adults from the Chilean Health Survey conducted between 2016 and 2017. Cardiorespiratory fitness was estimated from sex-specific equations for men and women and expressed as METs (Energy Metabolic Equivalent). Fitness levels were characterized by sociodemographics factors (age, sex, education, income and area of residency). Results: Fitness levels were higher in men (9.01 METs) than in women (6.76 METs) and in average decrease by 0.59 and 0.34 METs per each year increment in age for men and women, respectively. Fitness levels were 12.7 METs and 7.8 METs for 20-year-old men and women, respectively. However, fitness levels decreased to 7.8 METs and 4.3 METs in 90-year-old men and women, respectively. Fitness levels were also higher in individuals living in urban setting, those with higher education or income levels and lean individuals. Conclusions: This study reports fitness levels in a nationally representative sample of Chile. Fitness levels were higher in men than women however, its decline with age was more pronounce in men than women.

[Cardiopulmonary capacity in healthy subjects measured by direct method and field test]. / Capacidad cardiopulmonar en sujetos sanos medida por método directo y prueba de campo.

The six-minute walk test has been generally applied in people with pathologies and some studies have proposed models to predict maximum oxygen consumption. Our objective was to elaborate on an equation to predict the maximum oxygen consumption in the six-minute walking test for university students. A hundred and forty people participated in this study. The six-minute walking test was applied and after on a gradual exercise test was performed to determine the maximum oxygen consumption. A multivariate equation was developed and the analysis was done using the SPSS v.22 program (p < 0.05). The predictive model include gender, age, body mass index, distance performed and heart rate recovery (r = 0.83; p < 0.001). The equation fulfilled the assumptions of independence (p = 0.13), normality (p = 0.49) and homoscedasticity (p = 0.64). The Bland-Altman diagram indicated that there were no significant differences between the equation and the measurement of the maximum oxygen consumption (p = 0.89), with a confidence interval of 0.054 ml·kg·min-1 (95% CI [-0.72; 0.83]). The equation predicts the maximum oxygen consumption. It is suggested to evaluate university students considering biological and environmental differences between countries.

La prueba de caminata de seis minutos se ha aplicado generalmente en enfermos, y algunos estudios han propuesto modelos para predecir el consumo máximo de oxígeno. Nuestro objetivo fue elaborar una ecuación para predecir el consumo máximo de oxígeno en la prueba de caminata de seis minutos para estudiantes universitarios. Participaron 140 estudiantes. Se aplicó el test de marcha y después se realizó una prueba de ejercicio gradual para determinar el consumo máximo de oxígeno. Se elaboró una ecuación multivariada y el análisis se hizo con el programa SPSS v.22 (p < 0.05). El modelo predictivo incluyó el sexo, edad, índice de masa corporal, distancia recorrida y la frecuencia cardíaca de recuperación (r = 0.83; p < 0.001). La ecuación cumplió con los supuestos de independencia (p = 0.13), de normalidad (p = 0.49) y de homocedasticidad (p = 0.64). El diagrama de Bland-Altman indicó que no hubo diferencias significativas entre la ecuación y la medición del consumo máximo de oxígeno (p = 0.89), con un intervalo de confianza de 0.054 ml·kg·min-1 (95% IC [-0.72; 0.83]). La ecuación predice el consumo máximo de oxígeno. Se sugiere evaluar estudiantes universitarios considerando diferencias biológicas y ambientales entre países.

Capacidad cardiopulmonar en sujetos sanos medida por método directo y prueba de campo / Cardiopulmonary capacity in healthy subjects measured by direct method and field test

Resumen La prueba de caminata de seis minutos se ha aplicado generalmente en enfermos, y algunos estudios han propuesto modelos para predecir el consumo máximo de oxígeno. Nuestro objetivo fue elaborar una ecuación para predecir el consumo máximo de oxígeno en la prueba de caminata de seis minutos para estudiantes universitarios. Participaron 140 estudiantes. Se aplicó el test de marcha y después se realizó una prueba de ejercicio gradual para determinar el consumo máximo de oxígeno. Se elaboró una ecuación multivariada y el análisis se hizo con el programa SPSS v.22 (p < 0.05). El modelo predictivo incluyó el sexo, edad, índice de masa corporal, distancia recorrida y la frecuencia cardíaca de recuperación (r = 0.83; p < 0.001). La ecuación cumplió con los supuestos de independencia (p = 0.13), de normalidad (p = 0.49) y de homocedasticidad (p = 0.64). El diagrama de Bland-Altman indicó que no hubo diferencias significativas entre la ecuación y la medición del consumo máximo de oxígeno (p = 0.89), con un intervalo de confianza de 0.054 ml·kg·min-1 (95% IC [-0.72; 0.83]). La ecuación predice el consumo máximo de oxígeno. Se sugiere evaluar estudiantes universitarios considerando diferencias biológicas y ambientales entre países.

Abstract The six-minute walk test has been generally applied in people with pathologies and some studies have proposed models to predict maximum oxygen consumption. Our objective was to elaborate on an equation to predict the maximum oxygen consumption in the six-minute walking test for university students. A hundred and forty people participated in this study. The six-minute walking test was applied and after on a gradual exercise test was performed to determine the maximum oxygen consumption. A multivariate equation was developed and the analysis was done using the SPSS v.22 program (p < 0.05). The predictive model include gender, age, body mass index, distance performed and heart rate recovery (r = 0.83; p < 0.001). The equation fulfilled the assumptions of independence (p = 0.13), normality (p = 0.49) and homoscedasticity (p = 0.64). The Bland-Altman diagram indicated that there were no significant differences between the equation and the measurement of the maximum oxygen consumption (p = 0.89), with a confidence interval of 0.054 ml·kg·min-1 (95% CI [-0.72; 0.83]). The equation predicts the maximum oxygen consumption. It is suggested to evaluate university students considering biological and environmental differences between countries.

Mandibular slope: a reproducible and simple measure of horizontal gaze.

STUDY DESIGN: This study is a single-center retrospective radiographic review. OBJECTIVES: The objective of this study is to evaluate a novel measurement parameter, mandibular slope (MS), as a measure of horizontal gaze. INTRODUCTION: Assessment of sagittal spinal alignment is essential in the evaluation of spinal deformity patients. Ability to achieve a horizontal gaze, a parameter of sagittal alignment, is needed for the performance of daily activities. Standard measures of horizontal gaze, including the gold-standard chin-brow to vertical angle (CBVA) and the surrogate measures McGregor's line (McGS) and Chamberlain's line (CS), require high-quality imaging, precise head positioning, and reliance on difficult to view visual landmarks. A novel measurement parameter, MS, utilizing the caudal margin of the mandible on standard lateral spine radiographs is proposed. METHODS: 90 radiographs from spine deformity patients with or without spinal implants from a single center were evaluated. Three spine surgery fellows independently measured CBVA, McGS, CS, and MS at two timepoints at least one week apart to assess accuracy and reliability. MS was measured as the angle created by the inferior edge of the mandibular body and the horizontal. Formulas for calculating CBVA based on the above parameters were derived and compared to the actual CBVA. RESULTS: Mean age was 49.7 years, 76 females and 14 males. CBVA correlated with CS, McGS, and MS, r = 0.85, 0.81, and 0.80, respectively (p < 0.001). Standard error between real CBVA and calculated CBVA using CS (0.4 ± 4.79) and McGS (0.4 ± 3.9) was higher than that calculated using MS (- 0.2 ± 4.3). ICC demonstrated the highest inter-observer reliability with MS (0.999). MS had the highest intra-observer reliabilities 0.975, 0.981, and 0.988 (p < 0.001); CS and McGS also demonstrated high intra-observer reliability. CONCLUSIONS: MS is a promising measure of horizontal gaze that correlates highly with CBVA, has excellent intra- and inter-observer reliability with CBVA, and is easily measured using standard lateral spine radiographs.