Incidence and risk factors of distal adjacent disc degeneration in adolescent idiopathic scoliosis patients undergoing fusion surgery: a systematic review and meta-analysis

PURPOSE

The objective of this meta-analysis was to determine the incidence of disc degeneration in patients with surgically treated adolescent idiopathic scoliosis (AIS) and identify the associated risk factors.

METHODS

PubMed, EMBASE, Scopus, and Cochrane Collaboration Library databases were searched. The outcomes of interest were the incidence of disc degeneration, SRS-22, and radiological risk factors. The lower instrumented vertebra (LIV) was also evaluated. Fixed effects were used if there was no evidence of heterogeneity. Statistical analysis was performed using Review Manager.

RESULTS

A meta-analysis was conducted including nine studies with a total of 565 patients. The analysis revealed that the global incidence of intervertebral disc degeneration in patients with surgically treated AIS patients was 24.78% (95% CI 16.59-32.98%) 10 years after surgery, which significantly increased to 32.32% (95% CI 21.16-43.47% at an average of 13.8 years after surgery. Among patients with significant degenerative disc changes, the SRS-22 functional, self-image, and satisfaction domains showed significantly worse results (MD - 0.25, 95% CI - 0.44 to - 0.05; MD - 0.50, 95% CI - 0.75 to - 0.25; and MD - 0.34, 95% CI - 0.66 to - 0.03, respectively). Furthermore, instrumentation at or above the L3 level was associated with a lower incidence of intervertebral disc degeneration compared to instrumentation below the L3 level (OR 0.25, 95% CI 0.10-0.64). It was also found that the preoperative and final follow-up lumbar curve magnitudes (MD 8.11, 95% CI 3.82-12.41) as well as preoperative and final follow-up lumbar lordosis (MD 0.42, 95% CI - 3.81 to 4.65) were associated with adjacent disc degeneration.

CONCLUSIONS

This meta-analysis demonstrated that the incidence of intervertebral disc degeneration significantly increased with long-term follow-up using fusion techniques, reaching up to 32% when patients were 28 years of age. Incomplete correction of deformity and fusion of levels below L3, were identified as negative prognostic factors. Furthermore, patients with disc degeneration showed worse functional outcomes.

Elevated blood metal ion levels in patients undergoing instrumented spinal surgery: a systematic review and meta-analysis

BACKGROUND CONTEXT

Elevated blood metal levels have been reported in patients after spinal surgery using metallic implants. Although some studies have suggested an association between heightened blood metal concentrations and potential adverse effects, estimates of the incidence of abnormal metal levels after spinal surgery have been inconsistent.

PURPOSE

The aims of this systematic review and meta-analysis were to assess: (1) mean differences in blood metal ion levels between patients undergoing spinal fusion surgery and healthy controls, (2) odds of elevated blood metal ion levels after surgery compared to pre-surgery levels, and (3) pooled incidence of elevated blood metal ions overall and by metal type.

STUDY DESIGN

Systematic review and meta-analysis.

PATIENTS SAMPLE

The patient sample included 613 patients from 11 studies who underwent spinal surgery instrumentation.

OUTCOME MEASURES

Blood metal ion concentrations and the incidence of patients with elevated metal levels compared with in those the control group.

METHODS

A comprehensive search was conducted in PubMed, EMBASE, Scopus, and Cochrane Library to identify studies reporting blood metal ion levels after spinal fusion surgery. Mean differences (MD), odds ratios (OR), and incidence rates were pooled using random effects models. Heterogeneity was assessed using I2 statistics, and fixed-effects models were used if no heterogeneity was detected. Detailed statistical analysis was performed using the Review Manager version 5.4 software.

RESULTS

The analysis included 11 studies, with a total of 613 patients. Mean blood metal ion levels were significantly higher after spinal fusion surgery (MD 0.56, 95% CI 0.17-0.96; I2=86%). Specifically, titanium levels were significantly elevated (MD 0.81, 95% CI 0.32-1.30; I2=47%). The odds of elevated blood metal ions were higher after surgery (OR 8.17, 95% CI 3.38-19.72; I2=41%), primarily driven by chromium (OR 23.50, 95% CI 5.56-99.31; I2=30%). The incidence of elevated chromium levels was found to be 66.98% (95% CI 42.31-91.65).

CONCLUSION

In conclusion, blood metal ion levels, particularly titanium and chromium, were significantly increased after spinal fusion surgery compared to pre-surgery levels and healthy controls. Approximately 70% of the patients exhibited elevated blood levels of chromium and titanium.

Reply to Lemans et al. Comment on "Burgos et al. Fusionless All-Pedicle Screws for Posterior Deformity Correction in AIS Immature Patients Permit the Restoration of Normal Vertebral Morphology and Removal of the Instrumentation Once Bone Maturity Is Reached. J. Clin. Med. 2023, 12, 2408"

We thank Dr. Lemans and coworkers for their interest and knowledgeable comments [...].

Abolition of sagittal T7-T10 dynamics during forced ventilation in AIS patients with Lenke 1A curves

In healthy subjects, respiratory maximal volumes are highly dependent on the sagittal range of motion of the T7-T10 segment. In AIS, the abolition of T7-T10 dynamics related to the stiffness induced by the apex region in Lenke IA curves could harm ventilation during maximal breathing. The aim of this study was to analyze the dynamics of the thoracic spine during deep breathing in AIS patients and in healthy matched controls. This is a cross-sectional, case-control study. 20 AIS patients (18 girls, Cobb angle, 54.7 ± 7.9°; Risser 1.35 ± 1.2) and 15 healthy volunteers (11 girls) matched in age (12.5 versus 15.8 years mean age) were included. In AIS curves, the apex was located at T8 (14) and T9 (6). Conventional sagittal radiographs of the whole spine were performed at maximal inspiration and exhalation. The ROM of each spinal thoracic functional segment (T1-T7, T7-T10, T10-T12) and the global T1-T12 ROM were measured. In healthy subjects, the mean T1-T12 ROM during forced breathing was 16.7 ± 3.8. AIS patients showed a T1-T12 ROM of 1.1 ± 1.5 (p < 0.05), indicating a sagittal stiffness of the thoracic spine. A wide T7-T10 ROM (15.3 ± 3.0) was found in healthy controls (91.6% of the T1-T12 ROM). AIS patients showed only 0.4 ± 1.4 ROM at T7-T10 (36.4% of the T1-T12 ROM) (p < 0.001). There was a linear relationship between the magnitude of T7-T10 kyphosis in maximal exhalation and both FVC (% of predicted FVC) and FEV1. In conclusion, Lenke 1A AIS patients show a restriction of the thoracic spine motion with an almost complete abolition of T7-T10 ROM, a crucial segment for deep breathing. T7-T10 stiffness could explain the ventilatory limitations found in AIS patients.

Fusionless All-Pedicle Screws for Posterior Deformity Correction in AIS Immature Patients Permit the Restoration of Normal Vertebral Morphology and Removal of the Instrumentation Once Bone Maturity Is Reached

The aim of this study was to report the restoration of normal vertebral morphology and the absence of curve progression after the removal of instrumentation in AIS patients that underwent posterior correction of the deformity by a common all-screws construct without fusion. A series of 36 AIS immature patients (Risser 3 or less) were included in the study. Instrumentation was removed once the maturity stage was complete (Risser 5). The curve correction was assessed pre- and postoperatively, before instrumentation removal, directly post-removal, and more than two years after instrumentation was removed. Epiphyseal vertebral growth modulation was assessed by the coronal wedging ratio (WR) at the apical level of the main curve (MC). The mean preoperative coronal Cobb was corrected from 53.7° ± 7.5 to 5.5° ± 7.5° (89.7%) at the immediate postop. After implant removal (31.0 ± 5.8 months), the MC was 13.1°. T5-T12 kyphosis showed significant improvement from 19.0° before curve correction to 27.1° after implant removal (p < 0.05). Before surgery, the WR was 0.71 ± 0.06, and after removal, 0.98 ± 0.08 (p < 0.001). At the end of the follow-up, the mean sagittal range of motion (ROM) of the T12-S1 segment was 51.2 ± 21.0°. The SRS-22 scores improved from 3.31 ± 0.25 preoperatively to 3.68 ± 0.25 at the final assessment (p < 0.001). In conclusion, a fusionless posterior approach using common all-pedicle screws correctly constructed satisfactory scoliotic main curves and permitted the removal of instrumentation once bone maturity was reached. The final correction was highly satisfactory, and an acceptable ROM of the previously lower instrumented segments was observed.

Lower uterine segment thickness assessed by transvaginal ultrasound before labor induction: reproducibility analysis and relationship with delivery outcome

OBJECTIVES

To evaluate the reproducibility of lower uterine segment (LUS) thickness measurement before induction of labor (IOL), and to assess the relationship between LUS thickness and IOL outcomes.

METHODS

This was a prospective cohort study of pregnant women undergoing IOL at term, conducted in a single tertiary hospital between July 2014 and February 2017. Women with a singleton pregnancy at ≥ 37 weeks' gestation, with a live fetus in cephalic presentation and a Bishop score of ≤ 6, were eligible for inclusion. Both nulliparous and parous women, and those with a previous Cesarean section (CS), were eligible. All women underwent transvaginal ultrasound assessment before IOL admission, and cervical length and LUS thickness were measured offline after delivery. Maternal and obstetric characteristics and Bishop score were recorded. The main outcome was the overall rate of CS after IOL, and secondary outcomes were CS for either failure to progress in the active phase of labor or failed IOL, and CS for failed IOL only. Interobserver agreement for measurement of LUS thickness between two operators was assessed using the intraclass correlation coefficient (ICC) and Bland-Altman analysis with the ANOVA test to evaluate systematic bias. Univariable and multivariable analysis were employed to evaluate the relationship between clinical and sonographic characteristics and IOL outcomes.

RESULTS

Of 265 women included in the analysis, 195 (73.6%) had a vaginal delivery and 70 (26.4%) required a CS after IOL. Reproducibility analysis showed excellent interobserver agreement for the measurement of LUS thickness (ICC, 0.96 (95% CI, 0.93-0.98)). On Bland-Altman analysis, the mean difference in LUS thickness between the two operators was 0.15 mm (95% limits of agreement, -1.84 to 2.14 mm), and there was no evidence of systematic bias (ANOVA test, P = 0.46). Univariable analysis showed that LUS thickness was associated significantly with overall CS (P = 0.002), CS for failure to progress in the active phase of labor or failed IOL (P = 0.03) and CS for failed IOL (P = 0.037). On multivariable logistic regression analysis, LUS thickness was an independent predictive factor for overall CS (odds ratio (OR), 1.149 (95% CI, 1.031-1.281)) and CS for failure to progress in the active phase of labor or failed IOL (OR, 1.226 (95% CI, 1.039-1.445)).

CONCLUSIONS

In women undergoing IOL at term, measurement of LUS thickness is feasible and reproducible, and is associated significantly with IOL outcome. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Expected-value bias in mid-trimester preterm birth screening

OBJECTIVES

Cervical length (CL) measurement ≤ 25 mm on mid-trimester ultrasound scan is a known risk factor for preterm birth, for which vaginal progesterone is recommended. The aims of this study were to evaluate whether CL measurement is affected by observer bias and to assess the impact on short cervix prevalence of masking CL measurement during routine mid-trimester ultrasound scan.

METHODS

This was a flash study designed for a 2-month period (October and November 2018) at Cruces University Hospital (Bizkaia, Spain), in which all CL measurements from routine mid-trimester scans were masked. During the study period, there was no modification of the routine screening method, and women with a short cervix were prescribed 200 mg vaginal progesterone daily as per usual. The control group included women examined in a 2-month period (April and May 2018) prior to the study, in which CL measurements were taken as usual by a non-blinded operator. The primary outcome was the prevalence of short cervix in each group.

RESULTS

A total of 983 CL measurements were analyzed, including 457 in the blinded group and 526 in the control group. The prevalence of short cervix was 2.7% in the non-blinded group and 5.5% in the blinded group (P = 0.024). We identified a statistically significant difference in the incidence of CL of 24-25 mm between the two groups, with a lower prevalence in the non-blinded vs blinded group (0.6% vs 2.4%; P < 0.005). Moreover, the distribution of CL values was normal in the blinded group, in contrast to the non-blinded group, which was characterized by skewed distribution of CL values.

CONCLUSIONS

Expected-value bias exists and should be taken into account when measuring CL in mid-trimester preterm birth screening. Blinding has demonstrated to be an effective strategy to improve the performance of CL screening in clinical practice. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Cardiorespiratory function of patients undergoing surgical correction of Scheuermann's hyperkyphosis

The aim of this study was to analyze the impact of surgical correction of the thoracic deformity on the cardiorespiratory function of patients with moderate-severe Scheuermann’s hyperkyphosis (SK). A series of 23 adolescents with SK who underwent surgery through an only posterior approach using all pedicle screw constructs were included in the study. Cardiorespiratory parameters were measured during a maximal exercise tolerance test before and 2 years after surgery. Heart rate, oxygen saturation (SatO2), maximum oxygen uptake (VO2 max), ventilatory capacity at maximal exercise (VEmax), and energy costs were recorded. There were statistically significant differences in the forced vital capacity (FVC) (P < 0.05), total VO₂max (ml/min) (P < 0.01), maximum expired volume (VEmax) per minute (P < 0.01) and cardiovascular efficiency (HR/VO2 ratio) (P < 0.05). None of these changes were clinically relevant. There were no changes in the VO₂max per kg of body mass. The magnitude of the kyphosis correction did not correlate with the change in normalized VO2max or VEmax. In conclusion, patients with moderate-severe SK improve their baseline respiratory limitations and the tolerance to maximum exercise 2 years after surgery. However, the slight cardiorespiratory functional improvements should not necessarily be attributed to the surgery, and could also be caused solely by the residual growth of the lungs and thorax. Furthermore, respiratory functional changes are under thresholds considered as clinically relevant.

Non-uniform Segmental Range of Motion of the Thoracic Spine During Maximal Inspiration and Exhalation in Healthy Subjects

Background and Objective: To analyse the range of motion of the thoracic spine by radiographically measuring changes in the sagittal profile of different thoracic segments during maximal inspiration and exhalation. The starting hypothesis was that forced deep breathing requires an active, but non-uniform widening of the lordotic–kyphotic range of motion of the different thoracic segments.

Methods: Cross-sectional study. Participants were 40 healthy volunteers aged 21–60. Conventional anteroposterior and functional sagittal chest radiographs were performed during maximal inspiration and exhalation. The range of motion of each spinal thoracic functional segment, global T1–T12 motion, and the sagittal displacement of the thoracic column during breathing were measured. Considering the different type of ribs and their attachment the spine and sternum, thoracic segments were grouped in T1–T7, T7–T10, and T10–T12. The displacement of the thoracic spine with respect to the sternum and manubrium was also recorded.

Results: The mean difference from inspiration to exhalation in the T1–T12 physiologic kyphosis was 15.9° ± 4.6°, reflecting the flexibility of the thoracic spine during deep breathing (30.2%). The range of motion was wider in the caudal hemicurve than in the cranial hemicurve, indicating more flexibility of the caudal component of the thoracic kyphosis. A wide range of motion from inspiration to exhalation was found at T7–T10, responsible for 73% of T1–T12 sagittal movement. When the sample was stratified according to age ranges (20–30, 30–45, and 45–60 yr.), none of the measurements for inspiration or exhalation showed statistically significant differences.

Only changes at this level showed a positive correlation with changes in the global thoracic kyphosis (r = 0.794, p <0.001).

Conclusion: The range of motion of the thoracic spine plays a relevant role in respiration dynamics. Maximal inspiration appears to be highly dependent on the angular movements of the T7–T10 segment.

Early transcriptional responses in Solanum peruvianum and Solanum lycopersicum account for different acclimation processes during water scarcity events

Cultivated tomato Solanum lycopersicum (Slyc) is sensitive to water shortages, while its wild relative Solanum peruvianum L. (Sper), an herbaceous perennial small shrub, can grow under water scarcity and soil salinity environments. Plastic Sper modifies the plant architecture when suffering from drought, which is mediated by the replacement of leaf organs, among other changes. The early events that trigger acclimation and improve these morphological traits are unknown. In this study, a physiological and transcriptomic approach was used to understand the processes that differentiate the response in Slyc and Sper in the context of acclimation to stress and future consequences for plant architecture. In this regard, moderate (MD) and severe drought (SD) were imposed, mediating PEG treatments. The results showed a reduction in water and osmotic potential during stress, which correlated with the upregulation of sugar and proline metabolism-related genes. Additionally, the senescence-related genes FTSH6 protease and asparagine synthase were highly induced in both species. However, GO categories such as "protein ubiquitination" or "endopeptidase inhibitor activity" were differentially enriched in Sper and Slyc, respectively. Genes related to polyamine biosynthesis were induced, while several cyclins and kinetin were downregulated in Sper under drought treatments. Repression of photosynthesis-related genes was correlated with a higher reduction in the electron transport rate in Slyc than in Sper. Additionally, transcription factors from the ERF, WRKY and NAC families were commonly induced in Sper. Although some similar responses were induced in both species under drought stress, many important changes were detected to be differentially induced. This suggests that different pathways dictate the strategies to address the early response to drought and the consequent episodes in the acclimation process in both tomato species.

Low frequency of cytomegalovirus (CMV) disease despite high prevalence of CMV viraemia in patients with advanced HIV infection: a clinical and immunological 48-week follow-up study

OBJECTIVES

The aim of the study was to investigate the dynamics of cytomegalovirus (CMV) replication and CMV-specific immune response recovery after antiretroviral treatment (ART) initiation in patients with advanced HIV infection.

METHODS

A prospective observational study of patients with HIV infection and CD4 counts of < 100 cells/µL was carried out (September 2015 to July 2018). HIV viral load (VL), CD4 count and CMV VL were determined by quantitative polymerase chain reaction (PCR) at baseline and at 4, 12, 24 and 48 weeks, and CMV-specific immune response was determined by QuantiFERON-CMV assay at baseline and 48 weeks. All patients were started on ART but only those with CMV end-organ disease (EOD) received anti-CMV treatment.

RESULTS

Fifty-three patients with a median age of 43.6 [interquartile range (IQR) 36.7-52.4] years were included in the study. At baseline, the median CD4 count was 30 cells/µL (IQR 20-60 cells/µL) and the median HIV VL was 462 000 HIV-1 RNA copies/mL (IQR 186 000-1 300 000 copies/mL). At baseline, 32% patients had detectable CMV viraemia but none had detectable CMV viraemia at 48 weeks. Only one of 53 (1.9%) patients developed EOD during follow-up. Seven (13.2%) patients were lost to follow-up and six (11.3%) died; none of the deaths was related to CMV. Similar percentages of patients had a CMV-specific immune response at baseline (71.7%) and at 48 weeks (70.0%). The magnitude of this response tended to increase over time [median 1.63 (IQR 0.15-5.77) IU/mL at baseline vs. median 2.5 (IQR 0.1-8.325) IU/mL at 48 weeks; P = 0.11]. We did not find any risk factors associated with 48-week mortality.

CONCLUSIONS

Although the prevalence of CMV viraemia in patients with advanced HIV infection remains high, achieving a good immunological recovery through ART is enough to suppress CMV viraemia, without an increased risk of CMV EOD. The prevalence of a CMV-specific immune response was high and endured over time.

New approach for estimating risk of miscarriage after chorionic villus sampling

OBJECTIVE

To estimate the risk of miscarriage associated with chorionic villus sampling (CVS).

METHODS

This was a retrospective cohort study of women attending for routine ultrasound examination at 11 + 0 to 13 + 6 weeks' gestation at one of eight fetal-medicine units in Spain, Belgium and Bulgaria, between July 2007 and June 2018. Two populations were included: (1) all singleton pregnancies undergoing first-trimester assessment at Hospital Clínico Universitario Virgen de la Arrixaca in Murcia, Spain, that did not have CVS (non-CVS group); and (2) all singleton pregnancies that underwent CVS following first-trimester assessment at one of the eight participating centers (CVS group). We excluded pregnancies diagnosed with genetic anomalies or major fetal defects before or after birth, those that resulted in termination and those that underwent amniocentesis later in pregnancy. We used propensity score (PS) matching analysis to estimate the association between CVS and miscarriage. We compared the risk of miscarriage of the CVS and non-CVS groups after PS matching (1:1 ratio). This procedure creates two comparable groups balancing the maternal and pregnancy characteristics that are associated with CVS, in a similar way to that in which randomization operates in a randomized clinical trial.

RESULTS

The study population consisted of 22 250 pregnancies in the non-CVS group and 3613 in the CVS group. The incidence of miscarriage in the CVS group (2.1%; 77/3613) was significantly higher than that in the non-CVS group (0.9% (207/22 250); P < 0.0001). The PS algorithm matched 2122 CVS with 2122 non-CVS cases, of which 40 (1.9%) and 55 (2.6%) pregnancies in the CVS and non-CVS groups, respectively, resulted in a miscarriage (odds ratio (OR), 0.72 (95% CI, 0.48-1.10); P = 0.146). We found a significant interaction between the risk of miscarriage following CVS and the risk of aneuploidy, suggesting that the effect of CVS on the risk of miscarriage differs depending on background characteristics. Specifically, when the risk of aneuploidy is low, the risk of miscarriage after CVS increases (OR, 2.87 (95% CI, 1.13-7.30)) and when the aneuploidy risk is high, the risk of miscarriage after CVS is paradoxically reduced (OR, 0.47 (95% CI, 0.28-0.76)), presumably owing to prenatal diagnosis and termination of pregnancies with major aneuploidies that would otherwise have resulted in spontaneous miscarriage. For example, in a patient in whom the risk of aneuploidy is 1 in 1000 (0.1%), the risk of miscarriage after CVS will increase to 0.3% (0.2 percentage points higher).

CONCLUSIONS

The risk of miscarriage in women undergoing CVS is about 1% higher than that in women who do not have CVS, although this excess risk is not solely attributed to the invasive procedure but, to some extent, to the demographic and pregnancy characteristics of the patients. After accounting for these risk factors and confining the analysis to low-risk pregnancies, CVS seems to increase the risk of miscarriage by about three times above the patient's background risk. Although this is a substantial increase in relative terms, in pregnancies without risk factors for miscarriage, the risk of miscarriage after CVS remains low and similar to, or slightly higher than, that in the general population. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Accuracy of t-EMG stimulation of the middle pedicle track to prevent radiculopathies as a result of misplaced lumbar screws

OBJECTIVE

To describe the accuracy of middle pedicle track stimulation for the detection of pedicle breaches causing misplaced lumbar screws and subsequent neurological symptoms.

PATIENTS AND METHODS

In a comparative observational study with two cohorts, 1440 lumbar pedicle screws were implanted using the freehand technique in 242 patients undergoing surgery for spinal deformities. In the first two-year period (2011-2012), the accuracy of screw placement (802 screws) was assessed by conventional intraoperative palpation of the pedicle track, t-EMG screw stimulation, and fluoroscopic monitoring. In the second period (2012-2013), the middle aspect of the lumbar pedicle tracks was systematically stimulated with a probe (638 screws). When thresholds in the middle track showed <9 mA, potential neurological risk was considered, and therefore, new pedicle tracks were performed.

RESULTS

Six patients (4.4 %) in the first period presented postoperative radicular pain and a normal intraoperative screw t-EMG threshold. CT scans showed seven screws (0.9 %) with >2-mm medial-caudal invasion of the foramen. Before screw removal, t-EMG thresholds of these screws were again normal (≥10 mA). After removal of the screws. t-EMG of the middle part of the pedicle track showed thresholds below 9 mA (mean 5.2 mA). In the second period, the pedicle tracks were systematically stimulated. Low t-EMG thresholds (<9 mA) were found in 11 tracks (1.7 %) and were therefore reworked before screw placement. CT scans in these 10 patients showed that all of the 11 screws were correctly repositioned.

CONCLUSIONS

This study shows that caudal or medial pedicle cortical breaches can be detected effectively by stimulating the middle part of the pedicle track. This technique is strongly recommended to prevent postoperative lumbar radiculopathies due to screw malposition.

Adiposity-Age Distribution and Nutritional Status in Girls With Adolescent Idiopathic Scoliosis

STUDY DESIGN

Cross-sectional comparative study.

OBJECTIVES

To assess the adiposity-age distribution in girls with adolescent idiopathic scoliosis (AIS) and to define the prevalence of underweight, overweight, and obesity in these patients as compared with healthy controls.

SUMMARY OF BACKGROUND DATA

The current literature focusing the nutritional status of individuals with AIS does not provide data on the prevalence of overweight in these patients.

METHODS

The sample consisted of 112 adolescent girls with idiopathic scoliosis and 231 healthy age-matched girls from the same geographic region. Three different validated body mass index (BMI) cutoffs for adolescents were used to define the nutritional status. Adiposity was labeled according to Adiposity & Fat Distribution for Adolescents (AFAD-A) criteria.

RESULTS

There were significant differences in BMI and fat percentage according to age (p < .005) in both AIS patients and healthy controls. The overall prevalence of underweight was similar in both groups (scoliotic girls, 4.5%; controls, 4.8%). Obesity was more prevalent in AIS patients than in healthy controls. The World Health Organization-2007 and the Centers for Disease Control and Prevention cutoffs detected similar percentages of AIS girls with obesity (10.7%) and healthy controls (5.4%). The International Obesity Taskforce detected a 6.3% of AIS girls with obesity and only 3.0% in controls. Fat-age distribution gradually decreases from 11-13 to 16-17 years in AIS patients (p < .05). The overall prevalence of adolescents with fat overload (body fat index [BFI] >7.6) was similar in both groups (AIS, 0.9%; controls, 0.8%).

CONCLUSIONS

The proportion of adolescents with obesity was twofold higher among AIS girls than in age-matched healthy controls. However, in AIS girls, the BFI differed from that shown by healthy peers, being lower along the middle adolescence period (13-15 years). AIS girls showed an important increase in underweight at late adolescence (16-17 years).

LEVEL OF EVIDENCE

Level III, diagnostic.

Predictive performance of PAMG-1 vs fFN test for risk of spontaneous preterm birth in symptomatic women attending an emergency obstetric unit: retrospective cohort study

OBJECTIVE

To compare the performance of the placental alpha microglobulin-1 (PAMG-1) and fetal fibronectin (fFN) tests for the prediction of spontaneous preterm delivery in patients presenting to an emergency obstetric unit with threatened preterm labor, by conducting a retrospective audit of patient medical records from separate 1-year periods during which either fFN or PAMG-1 was used as the standard-of-care biochemical test.

METHODS

This was a retrospective cohort study based on chart review of electronic medical records of women with threatened preterm labor presenting at a level-III maternity hospital over two different periods: (1) the 'baseline' period (year 2012), during which the qualitative fFN test with a cut-off of 50 ng/mL was used as the standard-of-care biochemical test for the risk assessment of preterm delivery, and (2) the 'comparative' period (year 2016), during which the PAMG-1 test with a cut-off of 1 ng/mL was used as the standard-of-care biomarker test. Patients with a singleton pregnancy between 24 + 0 and 34 + 6 weeks' gestation with symptoms of early preterm labor, clinically intact membranes and cervical dilatation < 3 cm, who did not have a medically indicated preterm delivery within 14 days of testing, were selected for chart review and included in the analysis. Key parameters used for the analysis were biochemical test results, time of testing and time of delivery. Positive predictive value (PPV), negative predictive value (NPV), sensitivity, specificity, and positive and negative likelihood ratios (LR+ and LR-) for the prediction of spontaneous preterm delivery ≤ 7 and ≤ 14 days of presentation were calculated for the PAMG-1 and fFN tests.

RESULTS

Four hundred and twenty patients were identified as having presented with threatened preterm labor during the baseline period, of whom 378 (90.0%) met the eligibility criteria. Of these, 38 (10.1%) were fFN positive and 10 (2.6%) had spontaneous preterm delivery ≤ 7 days of presentation. PPV, NPV, LR+ and LR- of fFN were 7.9%, 97.9%, 3.2 and 0.8, respectively, for spontaneous preterm delivery ≤ 7 days. Four hundred and ten patients were identified as having presented with threatened preterm labor during the comparative period and 367 (89.5%) subjects met the eligibility criteria. Of these, 17 (4.6%) were PAMG-1 positive and 12 (3.3%) had spontaneous preterm delivery ≤ 7 days of presentation. PAMG-1 PPV and NPV were 35.3% and 98.3%, respectively, and LR+ and LR- were 16.1 and 0.5, respectively, for spontaneous preterm delivery ≤ 7 days.

CONCLUSIONS

Before switching to PAMG-1, fFN was the standard-of-care test for the risk assessment of spontaneous preterm delivery. This retrospective audit of each test's performance over separate 1-year periods shows that we were more than twice as likely to get a positive fFN test than a positive PAMG-1 test, while the rate of discharging women who ultimately delivered spontaneously within 14 days of testing was not affected. Furthermore, a positive PAMG-1 test was more than four times more reliable than a positive fFN test in predicting imminent spontaneous preterm delivery. The use of a more reliable biomarker that is associated with fewer false-positive results could lead to a reduction in unnecessary admissions, interventions and use of hospital resources. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Total vertebrectomy and spine shortening for the treatment of T12-L1 spine dislocation: Management with suboptimal resources

Total vertebrectomy with spine shortening has been reported for the treatment of difficult cases of traumatic spine dislocation, both in acute and chronic phase. We report an exceptional case of a five-week-old T12-L1 spine dislocation in a 25-year-old female with complete paraplegia as a result of trauma in Ciudad de León (Nicaragua). In view of the time since the dislocation, we performed a complete L1 vertebrectomy in order to reduce the dorsolumbar hinge. For osteosynthesis material we had only eight screws and two Steffee plates. We therefore introduced pedicle screws at levels T11, T12, L2 and L3 on the right side and T11, T12, L3 and L4 on the left, and performed manual reduction of the spine. Steffee plates were placed and we added sublaminar wires to reinforce the osteosynthesis. Fifteen months after surgery, there has been no neurological improvement.

Novel porcine experimental model of severe progressive thoracic scoliosis with compensatory curves induced by interpedicular bent rigid temporary tethering

Using flexible tethering techniques, porcine models of experimental scoliosis have shown scoliotic curves with vertebral wedging but very limited axial rotation. The aim of this experimental work was to induce a severe progressive scoliosis in a growing porcine model for research purposes. A unilateral spinal bent rigid tether was anchored to two ipsilateral pedicle screws in eight pigs. The spinal tether was removed after 8 weeks. Ten weeks later, the animals were sacrificed. Conventional radiographs and 3D CT-scans were taken to evaluate changes in the alignment of the thoracic spine. After the first 8 weeks of rigid tethering, all animals developed scoliotic curves (mean Cobb angle: 24.3°). Once the interpedicular tether was removed, the scoliotic curves progressed in all animals during 10 weeks reaching a mean Cobb angle of 49.9°. The sagittal alignment of the thoracic spine showed loss of physiologic kyphosis (Mean: -18.3°). Axial rotation ranged from 10° to 49° (Mean 25.7°). Release of the spinal tether results in progression of the deformity with the development of proximal and distal compensatory curves. In conclusion, temporary interpedicular tethering at the thoracic spine induces severe scoliotic curves in pigs, with significant wedging and rotation of the vertebral bodies, and true compensatory curves.

CLINICAL RELEVANCE

The tether release model will be used to evaluate corrective non-fusion technologies in future investigations. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:174-182, 2018.

Treatment options and predictive factors for recurrence and cancer-specific mortality in bladder cancer after renal transplantation: A multi-institutional analysis

OBJECTIVES

Bladder cancer (BC) in the transplanted population can represent a challenge owing to the immunosuppressed state of patients and the higher rate of comorbidities. The objective was to analyze the treatment of BC after renal transplant (RT), focusing on the mode of presentation, diagnosis, treatment options and predictive factors for recurrence.

MATERIAL AND METHODS

We conducted an observational prospective study with a retrospective analysis of 88 patients with BC after RT at 10 European centers. Clinical and oncologic data were collected, and indications and results of adjuvant treatment reviewed. The Kaplan-Meier method and uni- and multivariate Cox regression analyses were performed.

RESULTS

A total of 10,000 RTs were performed. Diagnosis of BC occurred at a median of 73 months after RT. Median follow-up was 126 months. Seventy-one patients (81.6%) had non-muscle invasive bladder cancer, of whom 29 (40.8%) received adjuvant treatment; of these, six (20.6%) received bacillus Calmette-Guérin and 20 (68.9%) mitomycin C. At univariate analysis, patients who received bacillus Calmette-Guérin had a significantly lower recurrence rate (P=.043). At multivariate analysis, a switch from immunosuppression to mTOR inhibitors significantly reduced the risk of recurrence (HR 0.24, 95% CI: 0.053-0.997, P=.049) while presence of multiple tumors increased it (HR 6.31, 95% CI: 1.78-22.3, P=.004). Globally, 26 patients (29.88%) underwent cystectomy. No major complications were recorded. Overall mortality (OM) was 32.2% (28 patients); the cancer-specific mortality was 13.8%.

CONCLUSIONS

Adjuvant bacillus Calmette-Guérin significantly reduces the risk of recurrence, as does switch to mTOR inhibitors. Multiple tumors increase the risk.

Experience in the treatment of osseous hydatidosis

Osseous hydatidosis is a very uncommon disease which often recurs after treatment. There is no well-established effective method of management. Radical excision may produce serious mutilation and often fails to control the disease. We have used oral mebendazole as adjuvant treatment in four patients. Two also underwent radical excision, one had received limited excision elsewhere and the other did not have operative treatment. The patients who underwent radical excision and the other who did not have an operation became and remain free of symptoms and are serologically negative.A combination of excision and treatment with mebendazole may have a role in the management of this complex disease.

Diagnosis and treatment for clinically localized prostate cancer. Adherence to the European Association of Urology clinical guidelines in a nationwide population-based study - GESCAP group

OBJECTIVE

To assess the adherence to European Association of Urology (EAU) guidelines in the management of prostate cancer (PCa) in Spain.

PATIENTS AND METHODS

Epidemiological, population-based, study including a national representative sample of 3,918 incident patients with histopathological confirmation during 2010; 95% of the patient's sample was followed up for at least one year. Diagnosis along with treatment related variables (for localized PCa -low, intermediate, high and locally-advanced by D'Amico risk stratification) was recorded. Differences between groups were tested with Chi-squared and Kruskal-Wallis tests.

RESULTS

Mean (SD) age of PCa patients was 68.48 (8.18). Regarding diagnostic by biopsy procedures, 64.56% of all patients had 8-12 cores in first biopsy and 46.5% of the patients over 75 years, with PSA<10ng/mL were biopsied. Staging by Computer Tomography (CT) or Bone Scan (BS) was used for determining tumor extension in 60.09% of high-risk cases and was applied differentially depending on patients' age; 3,293 (84.05%) patients received a treatment for localized PCa. Radical prostatectomy was done in 1,277 patients and 206 out of these patients also had a lymphadenectomy, being 4.64% low-risk, 22.81% intermediate-risk and 36.00% high-risk patients; 86.08% of 1,082 patients who had radiotherapy were treated with 3D or IMRT and 35.77% received a dose ≥75Gy; 419 patients were treated with brachytherapy (BT): 54.81% were low-risk patients, 22.84% intermediate-risk and 12.98% high-risk. Hormonotherapy (HT, n=521) was applied as single therapy in 9.46% of low-risk and 17.92% of intermediate-risk patients. Additionally, HT was combined with RT in 14.34% of lower-risk patients and 58.26% of high-risk patients, and 67.19% low-intermediate risk with RT and/or BT received neoadjuvant/concomitant/adjuvant HT. Finally, 83.75% of high-risk patients undergoing RT and/or BT also received HT.

CONCLUSIONS

Although EAU guidelines for PCa management are easily available in Europe, the adherence to their recommendations is low, finding the highest discrepancies in the need for a prostate biopsy and the diagnostic methods. Improve information and educational programs could allow a higher adherence to the guidelines and reduce the variability in daily practice. (Controlled-trials.com: ISRCTN19893319).

[Long term radiological outcomes of unstable thoraco-lumbar fractures without neurological deficit]

OBJECTIVE

To analyse the radiological outcomes in the long term of unstable thoraco-lumbar fractures.

MATERIAL AND METHODS

Retrospective review of 100 patients with unstable thoracolumbar fractures treated with posterolateral fusion and short screw fixation for compression and flexion-distraction type fractures, and long segment posterior fixation for fractures-dislocations or more than one vertebra fractured, between 2000 and 2010 at three different hospital centers. Six radiological parameters were measured annually during a 4-year period: Fracture angle, kyphotic deformity, sagittal index, percentage of compression, degree of displacement and deformation angle.

RESULTS

A total of 100 patients were included with a median age of 36,4 years and a median follow-up period of 7.2 years. Fracture angle rose from 11,6° to 14,5° (increase of 25%), kyphotic deformity from 14,5° to 16,7° (increase of 15,17%), sagittal index from 8,7 to 10,8 (increase of 24,13%), percentage of compression from 31,8% to 36,5% (increase of 6,88%), degree of displacement from 2,8mm to 4,6mm (increase of 14,77%) and deformation angle from 19.7° to 21.4° (increase of 8,62%).

DISCUSSION

All the radiological parameters studied lost correction throughout the 48 months of follow-up, being the fracture angle the most affected one. Nevertheless, the greatest loss of correction occurs in the first postoperative year, stabilizing the parameters afterwards over the 4 years of follow up. We routinely recommend the measurement of all previous parameters for the follow up of unstable thoracolumbar fractures.

Levofloxacin versus azithromycin for treating legionella pneumonia: a propensity score analysis

OBJECTIVES

Concerns have arisen regarding the equivalence of levofloxacin and some macrolides for treating community-acquired legionella pneumonia (LP). We aimed to compare the outcomes of current patients with LP treated with levofloxacin, azithromycin and clarithromycin.

METHODS

Observational retrospective multicentre study of consecutive patients with LP requiring hospitalization (2000-2014) conducted in two hospitals. The primary outcome assessed was 30-day mortality. To control for confounding, therapy was assessed by multivariate analysis.

RESULTS

We documented 446 patients with LP, of which 175 were treated with levofloxacin, 177 with azithromycin and 58 with clarithromycin. No significant differences in time to defervescence (2 (interquartile range (IQR) 1-4) versus 2 (IQR 1-3) days; p 0.453), time to achieve clinical stability (3 (2-5) versus 3 (2-5) days; p 0.486), length of intravenous therapy (3 (2-5.25) versus 4 (3-6) days; p 0.058) and length of hospital stay (7 (5-10) versus 6 (5-9) days; p 0.088) were found between patients treated with levofloxacin and those treated with azithromycin. Patients treated with clarithromycin had longer intravenous antibiotic treatment (3 (2-5.25) versus 5 (3-6.25) days; p 0.002) and longer hospital stay (7 (5-10) versus 9 (7-14) days; p 0.043) compared with those treated with levofloxacin. The overall mortality was 4.3% (19 patients). Neither univariate nor multivariate analysis showed a significant association of levofloxacin versus azithromycin on mortality (4 (2.3%) versus 9 (5.1%) deaths; p 0.164). The results did not change after incorporation of the propensity score into the models.

CONCLUSIONS

In our study, no significant differences in most outcomes were found between patients treated with levofloxacin and those treated with azithromycin. Due to the small number of deaths, results regarding mortality should be interpreted with caution.

Prevalence of endometriosis in women with systemic lupus erythematosus and Sjögren's syndrome

Endometriosis is associated with a number of immunologic alterations. It has been suggested that autoimmune disorders could be more frequent in patients with endometriosis. The aim of this study is to ascertain whether the prevalence of two well-known autoimmune diseases [systemic lupus erythematosus (SLE) and Sjögren's syndrome (SS)] is increased in women with endometriosis. The clinical charts of four different populations assisted at the same hospital were manually revised: (i) SLE population ( n = 120), (ii) SS ( n = 22), (iii) endometriosis ( n = 342) and (iv) control population ( n = 501 consecutive unselected asymptomatic women). Among SLE women, the prevalence of endometriosis was 1.67% (2/120), similar to the 4.39% prevalence of the control group (22/501), the OR being 0.37 [95%CI 0.09—1.59]. Among SS women, the prevalence of endometriosis was 9.09 (2/22), also similar to the control group OR 2.17 [95%CI 0.48—9.90]. In the same way, when comparing endometriosis cases with asymptomatic women, similar frequencies of SLE (0.58% and 0.2%) and SS were found (0% and 0%). Women with endometriosis do not have an increased prevalence of SLE or SS. Lupus (2007) 16, 736—740.

Determination of neutrophil CD64 expression as a prognostic biomarker in patients with community-acquired pneumonia

The expression of CD64 in neutrophils (nCD64) has shown utility in the diagnosis of sepsis. The aim of this study was to assess the usefulness of nCD64 expression to identify patients with community-acquired pneumonia (CAP) at risk of a poor outcome. A prospective study of nCD64 expression (determined by flow cytometry) in patients with CAP was performed. The sensitivity/specificity of nCD64 in predicting poor outcome [defined as intensive care unit (ICU) admission and/or clinical deterioration after arrival at the emergency department] was calculated. Eighty-three adults with CAP were included; 14.5 % had septic shock, 19.3 % required ICU admission, and 10.8 % presented clinical deterioration after admission. The mean of the median fluorescence intensity (MFI) of nCD64 expression was 1140 (±1097). Patients with nCD64 expression ≥2700 MFI had more clinical deterioration (36.4 vs. 7.2 %, p = 0.015) and more ICU admission (45.5 vs. 14.5 %, p = 0.028). To identify clinical deterioration and ICU admission, nCD64 expression showed a sensitivity of 44.4 and 33.3 % and a specificity of 90.1 and 90.8 %, respectively. The addition of nCD64 expression to the Pneumonia Severity Index and CURB-65 severity scores did not improve the accuracy of predicting these outcomes. Although nCD64 expression is associated with an increased risk of ICU admission or clinical deterioration after admission, its accuracy in predicting these poor outcomes is modest and does not significantly improve the predictive ability of the PSI and CURB-65 severity scores.

Treatment trends for clinically localised prostate cancer. National population analysis: GESCAP group

OBJECTIVES

To describe the established therapies for localised prostate cancer (PC) in Spain and to assess compliance with the 2010 UAE guidelines.

PATIENTS AND METHODS

This was an epidemiological, observational, prospective and multicentre study. Of the 3,918 patients diagnosed with PC during 2010, only those patients with localised PC were included. Follow-up was ultimately conducted for a minimum of one year from the diagnosis for 3,713 patients (94.77%). The treatment groups assessed were as follows: radical prostatectomy, radiation therapy, hormone therapy, brachytherapy, active surveillance or observation and experimental local treatment (cryotherapy or other treatment). Compliance with the recommendations of the EAU guidelines was studied, describing the treatment groups according to D'Amico risk stratification criteria (localised [low, intermediate and high risk] and locally advanced), age, PSA and Gleason score.

RESULTS

By applying the D'Amico criteria, we included 3,641 (92.93%) patients. Based on the UAE recommendations: 1) 68.87% of the patients at low-intermediate risk aged≤65 years underwent radical prostatectomy; 2) 34.51% of the patients>65 years at high risk with locally advanced disease were administered radiation therapy and hormone therapy; 3) 30.36% of the patients at high risk with locally advanced disease were only treated with hormone therapy; 4) 15.20% of the patients at low risk were only treated with brachytherapy; 5) active surveillance or observation was selected for 2.44% of the patients aged≤65 years and for 10.63% of the patients at low-intermediate risk who were>65 years. Lastly, 86.5% of the patients at low risk underwent a single treatment, and 43.62% of the patients at high risk with locally advanced disease underwent combined treatments.

CONCLUSIONS

This is the first national European study to evaluate the therapeutic management of localised PC based on the risk group to which the patient belonged. Most young patients (≤65 years) with low-intermediate risk localised PC were treated with surgery, which adheres to the recommendations of the 2010 UAE guidelines. Various therapeutic combinations have been employed for patients with high-risk, locally advanced localised tumours, revealing the need for a multidisciplinary approach (Controlled-trials.com number: ISRCTN19893319).

The effectiveness of electrocautery ablation for the treatment of high-grade anal intraepithelial neoplasia in HIV-infected men who have sex with men

OBJECTIVES

Electrocautery is one of the main treatment options for high-grade anal intraepithelial neoplasia (HGAIN). However, data regarding its efficacy are scarce. The aim of the study was to evaluate the effectiveness of electrocautery for the treatment of HGAIN.

METHODS

An observational study of HIV-infected men who have sex with men (MSM) who underwent screening for anal dysplasia was carried out. The on-treatment effectiveness of electrocautery was evaluated (according to biopsy findings measured 6-8 weeks after treatment) in patients with HGAIN. A complete response was defined as resolution of anal intraepithelial neoplasia (AIN), a partial response as regression to low-grade AIN and recurrence as biopsy-proven HGAIN during follow-up.

RESULTS

From May 2009 to November 2014, 21.9% (126 of 576) of patients screened were found to have HGAIN. Electrocautery effectiveness was evaluated in 83 patients. A complete response was observed in 27 patients [32.5%; 95% confidence interval (CI) 23.4-53.2%], a partial response in 28 patients (33.7%; 95% CI 24.5-44.4%) and persistence in 28 patients (33.7%; 95% CI 24.5-44.4%). The patients with the most successful results (81.8%) required two to four sessions of electrocautery. After a mean follow-up of 12.1 months, 14 of 55 patients with a response (25.4%; 95% CI 15.8-38.3%) developed recurrent HGAIN within a mean time of 29.9 months (95% CI 22-37.7 months). No patient progressed to invasive cancer during the study or developed serious adverse events after treatment. No factors associated with poor response or recurrences were observed.

CONCLUSIONS

Although electrocautery is the standard treatment for anal dysplasia, almost 50% of patients with HGAIN in our study did not respond or relapsed. New treatment strategies are necessary to optimize the management of anal dysplasia.

Radionuclide biological half-life values for terrestrial and aquatic wildlife

The equilibrium concentration ratio is typically the parameter used to estimate organism activity concentrations within wildlife dose assessment tools. Whilst this is assumed to be fit for purpose, there are scenarios such as accidental or irregular, fluctuating, releases from licensed facilities when this might not be the case. In such circumstances, the concentration ratio approach may under- or over-estimate radiation exposure depending upon the time since the release. To carrying out assessments for such releases, a dynamic approach is needed. The simplest and most practical option is representing the uptake and turnover processes by first-order kinetics, for which organism- and element-specific biological half-life data are required. In this paper we describe the development of a freely available international database of radionuclide biological half-life values. The database includes 1907 entries for terrestrial, freshwater, riparian and marine organisms. Biological half-life values are reported for 52 elements across a range of wildlife groups (marine = 9, freshwater = 10, terrestrial = 7 and riparian = 3 groups). Potential applications and limitations of the database are discussed.

Neurophysiological monitoring during acute and progressive experimentally induced compression injury of the spinal cord in pigs

PURPOSE

To evaluate the degree of acute or progressive lateral compression needed to cause neurologic injury to the spinal cord assessed by electrophysiological monitoring.

METHODS

In five domestic pigs, the spinal cord was exposed and compressed between T8-T9 roots using a precise compression device. Two sticks placed on both sides of the spinal cord were sequentially brought together (0.5 mm every 2 min), causing progressive spinal cord compression. Acute compression was reproduced by a 2.5-mm displacement of the sticks. Cord-to-cord evoked potentials were obtained with two epidural catheters.

RESULTS

Increasing latency and decreasing amplitude of the evoked potentials were observed after a mean progressive displacement of the sticks of 3.2 ± 0.9 mm, disappearing after a mean displacement of 4.6 ± 1.2 mm. The potential returned after compression removal (16.8 ± 3.2 min). The potentials disappeared immediately after an acute compression of 2.5 ± 0.3 mm, without any sign of recovering after 30 min.

CONCLUSIONS

The experimental model replicates the mechanism of a spinal cord injury caused by medially displaced screws into the spinal canal. The spinal cord had more ability for adaptation to progressive and slow compression than to acute mechanisms.

Congenital malformations, chromosomal abnormalities and perinatal results in IVF/ICSI newborns resulting from very poor quality embryos: a case-control study

AIMS

To explore whether the transfer of very poor quality (VPQ) embryos is associated with an increase in congenital malformations or perinatal problems.

METHODS

In this retrospective case-control study, 74 children conceived by in vitro fertilization (IVF) and/or intracytoplasmic sperm injection (ICSI) resulting exclusively from the transfer of VPQ embryos were compared with 1,507 children born after the transfer of top morphological quality (TQ) embryos over the same period of time in the same centers.

RESULTS

The prevalence of birth defects in children resulting from VPQ embryos was 1.35% (1/74), similar to the 1.72% (26/1,507) when only TQ embryos were transferred; the rate of chromosomal abnormalities detected was also similar (0.0 vs. 0.4%), as was perinatal mortality. After correcting for multiplicity (higher in the TQ group), the aforementioned parameters remained similar in the two groups.

CONCLUSION

Congenital malformations and perinatal complications do not seem to be more common in children born after transfer of VPQ embryos in IVF/ICSI cycles. Given our preliminary data, which need to be confirmed in much larger studies, when only VPQ embryos are available for transfer in IVF/ICSI cycles, we do not believe that they should be discarded with the intention of avoiding birth defects or perinatal complications.

Liver stiffness and aspartate aminotransferase levels predict the risk for liver fibrosis progression in hepatitis C virus/HIV-coinfected patients

OBJECTIVES

The aim of the study was to investigate liver fibrosis outcome and the risk factors associated with liver fibrosis progression in hepatitis C virus (HCV)/HIV-coinfected patients.

METHODS

We prospectively obtained liver stiffness measurements by transient elastography in a cohort of 154 HCV/HIV-coinfected patients, mostly Caucasian men on suppressive antiretroviral treatment, with the aim of determining the risk for liver stiffness measurement (LSM) increase and to identify the predictive factors for liver fibrosis progression. To evaluate LSM trends over time, a linear mixed regression model with LSM level as the outcome and duration of follow-up in years as the main covariate was fitted.

RESULTS

After a median follow-up time of 40 months, the median increase in LSM was 1.05 kPa/year [95% confidence interval (CI) 0.72-1.38 kPa/year]. Fibrosis stage progression was seen in 47% of patients, and 17% progressed to cirrhosis. Aspartate aminotransferase (AST) levels and liver fibrosis stage at baseline were identified as independent predictors of LSM change. Patients with F3 (LSM 9.6-14.5 kPa) or AST levels ≥ 64 IU/L at baseline were at higher risk for accelerated LSM increase (ranging from 1.45 to 2.61 kPa/year), whereas LSM change was very slow among patients with both F0-F1 (LSM  ≤ 7.5 kPa) and AST levels ≤ 64 IU/L at baseline (0.34 to 0.58 kPa/year). An intermediate risk for LSM increase (from 0.78 to 1.03 kPa/year) was seen in patients with F2 (LSM 7.6-9.5 kPa) and AST baseline levels ≤  64 IU/L.

CONCLUSIONS

AST levels and liver stiffness at baseline allow stratification of the risk for fibrosis progression and might be clinically useful to guide HCV treatment decisions in HIV-infected patients.

Impact of influenza season and environmental factors on the clinical presentation and outcome of invasive pneumococcal disease

Influenza and meteorological factors have been associated with increases in the incidence of invasive pneumococcal disease (IPD). However, scant data regarding the impact of influenza and the environment on the clinical presentation of IPD are available. An observational study of all adults hospitalized with IPD was performed between 1996 and 2012 in our hospital. The incidence of IPD correlated with the incidence rates of influenza and with environmental data. A negative binominal regression was used to assess the relationship between these factors. Clinical presentation of IPD during the influenza and non-influenza periods was compared. During the study, 1,150 episodes of IPD were diagnosed. After adjusting for confounding variables, factors correlating with the rates of IPD were the incidence of influenza infection (IRR 1.229, 95% CI 1.025-1.472) and the average ambient temperature (IRR 0.921, 95% CI 0.88-0.964). Patients with IPD during the influenza period had a worse respiratory status. A greater proportion of patients had respiratory failure (45.6% vs 52%, p = 0.032) and higher requirements for ICU admission (19.3% vs 24.7%, p = 0.018) and mechanical ventilation (11% vs 15.1%, p = 0.038). When we stratified by invasiveness of pneumococcal serotypes and the presence of comorbid conditions, the increase in the severity of clinical presentation was focused on healthy adults with IPD caused by nonhighly invasive serotypes. Beyond the increase in the burden of IPD associated with influenza, a more severe clinical pattern of pneumococcal disease was observed in the influenza period. This effect varied according to pneumococcal serotype, host comorbidities, and age.

Influence of hypotension and nerve root section on the ability to mobilize the spinal cord during spine surgery. An experimental study in a pig model

BACKGROUND CONTEXT

The correction of severe spinal deformities by an isolated posterior approach often involves cord manipulation together with hypotensive anesthesia. To date, the efficiency of methods to increase the tolerance of the cord to displacement and the influence of hypotension on this tolerance is yet to be assessed.

PURPOSE

The objective of this study was to determine the limits of cord displacement before the disappearance of neurophysiologic signals. The influence of the type of force applied, the section of the roots, and the induced hypotension on the cord's tolerance to displacement was also assessed.

STUDY DESIGN

Experimental study using a domestic pig model.

OUTCOME MEASURES

Successive records of cord-to-cord motor evoked potentials were obtained during displacement maneuvers. Displacing forces were released immediately after the absence of neurophysiologic signals.

METHODS

Surgical procedures were performed under conventional general anesthesia. The spinal cord and nerve roots from T6 to T10 levels were exposed by excision of the posterior elements, allowing for free cord movement. Three groups were established according to the method of spinal cord displacement: the separation (Group 1, n=5), the root stump pull (Group 2, n=5), and the torsion groups (Group 3, n=5). An electromechanical external device was used to apply the displacing forces. The three displacement tests were repeated after sectioning the adjacent nerve roots. The experiments were first carried out under normotension and afterward under induced hypotension.

RESULTS

In Group 1, evoked potential disappeared with a displacement of 10.1±1.6 mm with unharmed roots and 15.3±4.7 mm after the sectioning of four adjacent roots (p<.01). After induced hypotension, potentials were lost at 4.0±1.2 mm (p<.01). In Group 2, the absence of potentials occurred at 20.0±4.3 mm and increased to 23.5±2.1 mm (p<.05) after cutting the two contralateral roots. Under hypotensive conditions, the loss of neurophysiologic signals was detected at 5.3±1.2 mm (p<.01). In Group 3, the cord allowed torsion of 95.3±.2° that increased to 112.4±7.1° if the contralateral roots were cut. Under hypotension, the loss of potentials was found at 20±6.2° (p<.01).

CONCLUSIONS

In this experimental model, it was possible to displace the thoracic spinal cord by a distance superior to the spinal cord width without suffering neurophysiologic changes. The limits of cord displacement increase when the adjacent nerve roots are sacrificed. Induced hypotension had a dramatic effect on the tolerance of the spinal cord for displacement. This work has an important clinical significance because induced hypotension during specific spine surgery procedures requiring spinal cord manipulation in humans may increase the risk of neurologic spinal cord injury.

Intraoperative Neurophysiological Changes Induced by Thoracic Pedicle Screws Intentionally Placed Within the Spinal Canal: An Experimental Study in Pigs

STUDY DESIGN

Experimental study, OBJECTIVES: To document and analyze the neurophysiological changes during spinal cord monitoring when thoracic pedicle screws are intentionally placed within the spinal canal.

SUMMARY OF BACKGROUND DATA

Although the rate of misplaced screws is relatively high, few patients have neurological impairment. This suggests that a significant degree of medullary displacement and/or compression is necessary to produce neurophysiological changes.

METHODS

The spinal cord of 3 experimental pigs was surgically exposed at 3 different levels (T11, T9, and T6). Two pedicle screws were placed within the spinal canal at each vertebral level under direct vision. One was placed on the lateral edge of the dural sac, causing only a slight cord displacement; a second screw was placed in the middle of the spinal canal, producing marked displacement of the neural structures. During the procedure, neurophysiological monitoring of the spinal cord was performed.

RESULTS

No neurophysiological changes were observed in any screws placed at the lateral edge of the dural sac for 20 minutes after screw placement. When the screws were placed in the center of the spinal canal, neurophysiological changes occurred with a mean latency of 10.1 ± 2.1 minutes, and at 11.6 ± 1.9 minutes there was complete loss of the spinal cord evoked potentials in all cases. After these centered screws were removed, evoked potentials began to recover, with a latency of 9.7 ± 3.0 minutes in 7 of 9 cases.

CONCLUSIONS

Neurophysiological monitoring of the spinal cord does not detect moderate compression even 20 minutes after neural compression. Only thoracic pedicle screws provoking marked displacement of the spinal cord were able to cause delayed neurophysiological changes leading to loss of spinal cord evoked potentials, which in 22% of cases did not recover after the pedicle screw was removed.

Resultado a largo plazo de las fusiones largas espinopelvicas en escoliosis: importancia de la edad, la capacidad de marcha y el tipo de fijación ilíaca

OBJETIVO: Conocer los factores que influyen en los fracasos instrumentales lumbosacros después de fusiones espinopélvicas largas. MÉTODO: Estudio retrospectivo de pacientes diagnosticados con escoliosis, tratados quirúrgicamente por vía posterior, realizándo se fusión espinopélvica de T2 o T3 a ilíaco, utilizando tornillos pediculares e ilíacos. Se analizaron los fracasos instrumentales y su asociación con diferentes parámetros clínicos y radiológicos. RESULTADOS: Se presentan 44 pacientes con edad promedio de 24 años, con diferentes etiologías. El valor promedio preoperatorio de la curva mayor era de 74,2º, y en la revisión final la corrección promedio fue 67%. El desequilibrio anteroposterior y la inclinación pélvica, la cifosis torácica, la lordosis lumbar y el desequilibrio lateral mejoraron significativamente en la revisión final. Hubo 41% de fracasos de instrumentación, todos a nivel lumbosacro. Se encontró asociación significativa con más fracasos instrumentales en mayores de 17 años y en los que tenían deambulación autónoma. En 24 pacientes, se utilizó un solo tornillo ilíaco bilateralmente y en 20 pacientes, dos o más. Los dos grupos tuvieron una incidencia similar de fracasos. En el grupo de dos o más tornillos solo existieron roturas de barras sin desanclajes, ni lisis. El uso de implantes intersomáticos de L3 a S1 o cerclajes sublaminares con una tercera barra disminuyó la incidencia de fracasos. CONCLUSIONES: En esta serie se presentaron un 41% de fracasos instrumentales, todos localizados a nivel lumbosacro. Los pacientes con capacidad de deambulación autónoma y mayores de 17 años presentaron significativamente más fallas instrumentales. En los que se realizó fusión intersomática L3-S1 o una tercera barra con cerclajes sublaminares, disminuyó la incidencia.

Resultados postoperatorios inmediatos y a largo plazo de un abordaje mini-invasivo para la corrección de escoliosis idiopática del adolescente

OBJETIVO: Analizar los resultados de una nueva técnica quirúrgica mínimamente invasiva (MIS, por el inglés "minimally invasive surgery") por vía posterior aislada para la corrección quirúrgica de la escoliosis idiopática del adolescente (EIA). MÉTODOS: Se comparan dos grupos de pacientes con EIA tipo 1A de Lenke, similares en cuanto a edad, género, ángulo de Cobb, ápex de la curva, rotación vertebral, cifosis torácica, niveles de fusión, tipo de instrumentación y seguimiento. El Grupo 1 fue tratado con la técnica mínimamente invasiva que describiremos y el Grupo 2, de forma convencional. Se analizaron el tiempo quirúrgico, la pérdida sanguínea intraoperatoria, los requerimientos analgésicos en el postoperatorio inmediato, la estancia hospitalaria, la tasa de mal posición de los tornillos, la pérdida de corrección, la tasa de pseudoartrosis y la movilización de implantes. RESULTADOS: En el Grupo 1 (MIS) la cirugía disminuyó significativamente el sangrado y presentó menor número de casos de tornillos mal posicionados en la concavidad que el grupo tratado de forma convencional; sin embargo la cirugía tuvo mayor duración. Ambos grupos tuvieron requerimientos analgésicos similares y la estancia hospitalaria no presentó diferencias. A largo plazo en ninguno de los dos grupos se encontraron casos de no-unión, pérdidas de corrección, ni movilización de los implantes. CONCLUSIONES: La técnica MIS demostró prolongación del tiempo quirúrgico y menores pérdidas hemáticas, sin disminuir los requerimientos analgésicos ni la estancia hospitalaria. La corrección inicial de la escoliosis por la convexidad disminuyó la incidencia de tornillos mal posicionados en la concavidad, no dio lugar a pérdidas de corrección, movilización de implantes y no-unión.

[Intravenous infusion of adult adipose tissue stem cells for repairing spinal cord ischaemic lesions. An experimental study on animals]

OBJECTIVE

To assess if a peripheral intravenous infusion of adipose tissue stem cells (ATSC), after an ischemic spinal cord injury can promote selective cell migration and cell survival in the damaged neural tissue. ANIMALS AND METHOD: An ischaemic spinal cord injury was provoked by trapping the abdominal aorta for 20 minutes in 11 male New Zealand rabbits (2.5±0.5kg). They were randomised into two groups: one group (n=5) received an intravenous transfusion of 10±2×10(6) ATSC at 24 hours from the injury, and the control group (n=6) were only given the vehicle. The functional status was assessed, using the Tarlov scale at 24h, and 7 and 14 days. The animals were sacrificed at 14 days and a histological and immunohistochemical study was performed.

RESULTS

Complete paraplegia was achieved in both groups. There were no significant differences as regards neurological recovery, which was nil in both cases. In the histological and immunohistochemical study, it was tested to see if there was any bromodeoxyuridine-marked ATSC in the area of the lesion, but there was only a small amount.

CONCLUSION

ATSC are able to migrate and survive in the injured spinal cord after aortic ischaemia after they have been administered intravenously. Intravenous infusion is a harmless procedure with no side effect. No neurological recovery was achieved.