Scaling analysis of core pressure drop in reduced height integral test facility

Integral test plays essential role to assess the design of the emergency cooling system of nuclear reactors. Different from full height integral test facilities, reduced height integral test facilities have new problems on the pressure drop scaling. This paper mainly focuses on scaling of pressure drop across the core as it is the major pressure drop in primary loop. The analysis of pressure drop across the core has been divided into three terms and each term has been discussed separately based on two conditions: the normal operation condition and natural circulation condition. After that, the total pressure drop ratios under these two conditions have been discussed.

Research on thermal-hydraulic behavior in the spent fuel pool using a full-height experimental facility

During accident scenarios the effective cooling of spent fuel directly affects the safety of nuclear power plants. Two experiments were performed in a full-height facility to study the thermal-hydraulic behavior in spent fuel pool. In spent fuel pool boiling experiment, the heat transfer characteristics are related to the flow patterns. However, the flow pattern in narrow and long channel is different from the traditional flow pattern. In the semi-dry of heated rod, wall temperature oscillation occurs for a long time. In the spent fuel pray experiment, the liquid film thickness varies randomly with time and space. As the spray flow density increase, the maximum wall temperature decrease gradually with a certain linear characteristic.

Criteria and comparison of thermal stratification between PRHR HX heating and ADS spraying process in IRWST based on a down-scaled experimental facility

The overall scaled-down separate-effects IRWST&PRHR HX&ADS test facility has been built to simulate the thermal hydraulic behavior of the passive residual heat removal system under accident conditions. The measured 3-D temperature and velocity results show obvious thermal stratification in IRWST. The Richardson number (Ri) could be used to predict the occurrence of possible thermal stratification, and the Stratification number (Str) to evaluate the thermal stratification extent. Both dimensionless parameters provide criteria for thermal stratification and experimental references for the design and operation of engineering equipment.

Comparison of gefitinib and platinum-based chemotherapy and only platinum-based chemotherapy to treat lung adenocarcinoma

To study the curative effects and safety for patients who adopt both gefitinib and platinum-based chemotherapy or only platinum-based chemotherapy in the treatment of lung adenocarcinoma, 80 EGFR mutation-positive lung adenocarcinoma patients in stage IIIB/IV were divided into two groups. Half of them received both gefitinib and standard chemotherapy (group A), and the others (group B) received only standard chemotherapy. Overall response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS) and the related toxicities of both groups were recorded in order to take certain nursing measures for a variety of toxicities. Next, statistical methods were used to analyze the curative effects and safety of the two treatments. The results showed that ORR, DCR and median progression-free (mPFS) survival of the two groups of patients showed no statistical difference (P >0.05). However, group A (18.56 months) had a longer median overall survival (mOS) than group B (14.87 months), which was of statistical significance (P less than 0.05). Nausea and loss of appetite were common mild adverse reactions, and anemia and leukocytopenia were moderate common adverse reactions. The difference between these two groups of patients regarding adverse reactions was not statistically significant (P>0.05). In conclusion, the two treatments have similar safety, but lung adenocarcinoma patients with drug resistance during stage IIIB/IV after using first-line gefitinib therapy have lower survival benefits than patients who take both gefitinib and platinum-based chemotherapy.

The relationship between different measures of feed efficiency and feeding behavior traits in Duroc pigs

Utilization of feed in livestock species consists of a wide range of biological processes, and therefore, its efficiency can be expressed in various ways, including direct measurement, such as daily feed intake, as well as indicator measures, such as feeding behavior. Measuring feed efficiency is important to the swine industry, and its accuracy can be enhanced by using automated feeding systems, which record feed intake and associated feeding behavior of individual animals. Each automated feeder space is often shared among several pigs and therefore raises concerns about social interactions among pen mates with regard to feeding behavior. The study herein used a data set of 14,901 Duroc boars with individual records on feed intake, feeding behavior, and other off-test traits. These traits were modeled with and without the random spatial effect of Pen_Room, a concatenation of room and pen, or random social interaction among pen mates. The nonheritable spatial effect of common Pen-Room was observed for traits directly measuring feed intake and accounted for up to 13% of the total phenotypic variance in the average daily feeding rate. The social interaction effect explained larger proportions of phenotypic variation in all the traits studied, with the highest being 59% for ADFI in the group of feeding behaviors, 73% for residual feed intake (RFI; RFI4 and RFI6) in the feed efficiency traits, and 69% for intramuscular fat percentage in the off-test traits. After accounting for the social interaction effect, residual BW gain and RFI and BW gain (RIG) were found to have the heritability of 0.38 and 0.18, respectively, and had strong genetic correlations with growth and off-test traits. Feeding behavior traits were found to be moderately heritable, ranging from 0.14 (ADFI) to 0.52 (average daily occupation time), and some of them were strongly correlated with feed efficiency measures; for example, there was a genetic correlation of 0.88 between ADFI and RFI6. Our work suggested that accounting for the social common pen effect was important for estimating genetic parameters of traits recorded by the automated feeding system. Residual BW gain and RIG appeared to be two robust measures of feed efficiency. Feeding behavior measures are worth further investigation as indicators of feed efficiency.

Host contributes to longitudinal diversity of fecal microbiota in swine selected for lean growth

BACKGROUND

In pigs, gut bacteria have been shown to play important roles in nutritional, physiological, and immunological processes in the host. However, the contribution of their metagenomes or part of them, which are normally reflected by fragments of 16S rRNA-encoding genes, has yet to be fully investigated.

RESULTS

Fecal samples, collected from a population of crossbred pigs at three time points, including weaning, week 15 post weaning (hereafter "week 15"), and end-of-feeding test (hereafter "off-test"), were used to evaluate changes in the composition of the fecal microbiome of each animal over time. This study used 1205, 1295, and 1283 samples collected at weaning, week 15, and off-test, respectively. There were 1039 animals that had samples collected at all three time points and also had phenotypic records on back fat thickness (BF) and average daily body weight gain (ADG). Firmicutes and Bacteroidetes were the most abundant phyla at all three time points. The most abundant genera at all three time points included Clostridium, Escherichia, Bacteroides, Prevotella, Ruminococcus, Fusobacterium, Campylobacter, Eubacterium, and Lactobacillus. Two enterotypes were identified at each time point. However, only enterotypes at week 15 and off-test were significantly associated with BF. We report herein two novel findings: (i) alpha diversity and operational taxonomic unit (OTU) richness were moderately heritable at week 15, h2 of 0.15 ± 0.06 to 0.16 ± 0.07 and 0.23 ± 0.09 to 0.26 ± 0.08, respectively, as well as at off-test, h2 of 0.20 ± 0.09 to 0.33 ± 0.10 and 0.17 ± 0.08 to 0.24 ± 0.08, respectively, whereas very low heritability estimates for both measures were detected at weaning; and (ii) alpha diversity at week 15 had strong and negative genetic correlations with BF, - 0.53 ± 0.23 to - 0.45 ± 0.25, as well as with ADG, - 0.53 ± 0.32 to - 0.53 ± 0.29.

CONCLUSIONS

These results are important for efforts to genetically improve the domesticated pig because they suggest fecal microbiota diversity can be used as an indicator trait to improve traits that are expensive to measure.

Clinical features and outcomes in secondary adult hemophagocytic lymphohistiocytosis

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a rare clinical syndrome characterized by an infrequent but immune-mediated life-threatening disease, with confusing clinical manifestations, rapidly deteriorating health, high morbidity and mortality and challenging diagnosis.

AIM

The purpose of this study was to improve the recognition and understanding of HLH.

DESIGN

Retrospective observational cross-sectional study.

METHODS

Data were collected for all cases of adult patients diagnosed with HLH in a large cohort managed at a single medical center from January 2011 to December 2015.

RESULTS

The median age was 52 years (range 18-90 years) and 123 (60.0%) were male. Over 95% patients manifested fever, hyperferritinemia and elevated lactate dehydrogenase. Underlying triggers of HLH were as follows: 119 (58.0%) malignancies, 83 (40.5%) infections, 14 (6.8%) unknown triggers and 14 (6.8%) autoimmune disorders. The median overall survival was 55 days. And elderly patients (age ≥60 years) had a markedly worse survival compared with young patients (age <60 years) (median overall survival 24 days vs. 159 days, respectively; P <0.001). In a multivariable analysis, platelet <40 × 109/l (HR = 2.534; 95% CI 1.152-5.573; P = 0.021), PT prolonged >3 s (HR = 1.909; 95% CI 1.127-3.234; P = 0.016) and malignancy (HR = 1.614; 95% CI 1.008-2.582; P = 0.046) were correlated with poor survival.

CONCLUSION

HLH adult patients had very complex clinical manifestations as well as underlying diseases. Patients with PLT <40 ×109/l, PT prolonged >3 s and malignancy had inferior survival. It is of great importance to improve our understanding of this syndrome.

The MTHFR polymorphism affect the susceptibility of HCC and the prognosis of HCC liver transplantation

BACKGROUND

Methylenetetrahyfrofolate reductase (MTHFR) is the key enzyme for one carbon and folate metabolism. Previous studies have drawn different conclusions about the relationship between the mutation of MTHFR and hepatocellular carcinoma (HCC) occurrence. MTHFR polymorphisms' influence on liver transplantation for HCC recurrence has yet not been reported. Aim of this study was to clarify the impact of MTHFR polymorphism on hepatocarcinogenesis and the prognosis of liver transplant recipient with HCC.

METHODS

This study enrolled 244 HCC patients and 487 healthy individuals in Chinese Han population to analyze the influence of MTHFR polymorphism on HCC susceptibility first. Furthermore, this research choose another 100 donors' and 104 recipients' specimens to detect the association between polymorphism of MTHFR and post-transplant HCC recurrence.

RESULT

rs1801131 polymorphism A to C was associated with the occurrence of HCC in Chinese Han population (p < 0.05), especially in age exceeding 50 years (p < 0.01). No association was observed with rs1801133 polymorphism and HCC occurrence. The mean tumor-free survival for recipients with donor liver graft rs1801133 C to T variants was shorter than CC type (12.63 ± 3.84 vs 22.43 ± 4.74 months, p < 0.05). Multivariate analysis revealed that Donor rs1801133 and Hangzhou criteria were two independent prognostic factors for tumor-free survival (p < 0.05). Neither donor rs1801131 polymorphism nor recipients' MTHFR polymorphisms was associated with HCC recurrence.

CONCLUSION

This study demonstrated that MTHFR polymorphism was associated with HCC occurrence and post-transplant HCC recurrence. rs1801131 mutation A to C is a valuable molecular biomarker for predicting HCC occurrence in Chinese Han population. Donor MTHFR rs1801133 C to T polymorphism could present as a promising prognostic biomarkers for HCC recurrence in liver transplant recipients.

A high precision flat crystal spectrometer compatible for ultra-high vacuum light source

We report on a flat crystal spectrometer (FCS) featuring a differently pumped rotary feedthrough and double detectors connected to a crystal chamber by extendable bellows built at the Shanghai EBIT Laboratory. It was designed to overcome defects such as oil contamination, little distance from the detector to the crystal and others of an early FCS equipped at the same laboratory, but still keeps a large detectable angle range of detectors and brings new features and functions such as the Bond method measurement and double-crystal measurement which are based on the two-detector and large bellow design. This new FCS could cover an energy range of measurable photons from 570 eV to 10 keV and reach a vacuum better than 6 × 10^-10 Torr and thus is compatible for coupling directly to ultra-high vacuum light sources. Off-line tests of the FCS were undertaken where Kα x-rays from solid titanium were measured and analyzed. Measurements of transitions in He-like argon ions were performed when the spectrometer was directly connected to Shanghai EBIT, and the width of the x-ray source was monitored simultaneously using an x-ray slit imaging system. An observed spectral line broadening was 0.869 eV corresponding to a resolving power of 3600, including Doppler broadening of the x-ray source. Taking account of the measured source width, we made simulations using the SHADOW 3 code and got a nominal resolving power of 6500 for the spectrometer. This high nominal resolving power is due to a longer distance from the crystal to the detector, comparing with that in the early FCS.

[Evaluation of endometriosis fertility index in follow-up treatment of endometriosis combined with infertility patients after laparoscopic surgery]

Objective: To explore the application of endometriosis fertility index (EFI) in guidance after laparoscopic surgery of endometriosis patients combined with infertility and to explore methods to improve pregnancy rate in different EFI groups. Methods: A prospective research was done in endometriosis patients combined with infertility in Beijing Obstetrics and Gynecology Hospital from January 2010 to June 2011, after laparoscopic surgery, these 146 patients were divided into 3 groups by EFI score. Using different pregnancy guidance, these patients had 5 years follow-up. Results: (1) The 5 years overall pregnancy rate was 89.0% (130/146). The pregnancy rate was 95.7% (45/47) in EFI≥9 group, 92.8% (77/83) in EFI 5-8 group and 8/16 in EFI≤4 group, three groups were all reach satisfactory pregnancy rate; the rate of the first two groups had no statistically significance (P=0.498), but had significant difference with the last group (P<0.01). (2) In EFI≥5 patients, pregnancy rate was the highest in 6 months after operation; in EFI≥9 group, the pregnancy rate was 66.7% (30/45), and EFI 5-8 group was 50.6% (39/77). (3) EFI≥9 group had the highest natural pregnancy rate [83.6% (46/55)], natural pregnancy rate was significant statistical different in different EFI groups (P=0.001). Conclusions: EFI score is a useful evaluation in predicting and guiding pregnancy in endometriosis patients combined with infertility after laparoscopic surgery. EFI score guidance, strict post-operation management and positive pregnancy scheme could significantly improve the pregnancy rate of endometriosis patients with infertility.

[Effects and related mechanism of bivalirudin on the survival of random skin flap on the back of rat]

Objective: To investigate the effects and related mechanism of bivalirudin on the survival of random skin flap on the back of rat. Methods: Thirty SD rats were divided into bivalirudin group and normal saline group according to the random number table, with 15 rats in each group. The random flap model with size of 9 cm×3 cm was reproduced on the back of rats in two groups. Immediately post injury, rats in bivalirudin group were intraperitoneally injected with 5 mg/mL bivalirudin (0.8 mL/kg), while rats in normal saline group were intraperitoneally injected with normal saline (0.8 mL/kg) once a day. The continuous injection lasted for 7 days. The flap was divided into distal area, middle area and proximal area averagely based on the flap blood supply. On post injury day (PID) 1, 3, and 7, the overall survival of each area of flap was observed with naked eyes. On PID 7, the survival rate of flap was calculated, and then the morphology of skin tissue at the center of the three areas of flap was observed by HE staining, the microvessel density (MVD) of the middle area of flap was calculated, and the expression of vascular endothelial growth factor (VEGF) of the middle area of flap was detected with immunohistochemical staining. Data were processed with t test. Results: (1) On PID 1, flaps of rats in two groups had different degrees of swelling, mainly concentrated in distal area, but there was no obvious necrosis. The middle area and proximal area of flaps in two groups were survived. On PID 3, the necrosis of flaps of rats in two groups was concentrated in the middle area, while the proximal area of flap was still in survival state, and most distal area of flap was necrosis with a little scab. On PID 7, the necrosis of middle area of flaps of rats in two groups was gradually fused, and the survival area of flap of rats in bivalirudin group was larger than that in normal saline group. The distal area of flap was almost necrotic, and the proximal area of flap was almost survived. (2) On PID 7, the survival rate of flap of rats in bivalirudin group was (64±4)%, significantly higher than that in normal saline group [(45±3)%, t=13.49, P<0.01]. (3) On PID 7, the histological morphology of distal area of flap of rats in two groups was similar, the inflammatory cells were infiltrated abundantly, and tissue edema was obvious. A large number of new blood vessels appeared in the middle area of flap of rats in bivalirudin group, with the formation of collateral vessels, and basic dilation of new blood vessels was seen. There were fewer new blood vessels appeared in the middle area of flap of rats in normal saline group, and dilation of new blood vessels was not obvious. There was little inflammatory cells infiltration in the proximal area of flap of rats in two groups. Compared with that in normal saline group, tissue edema extent of proximal area of flap of rats in bivalirudin group was less, and expansion was observed in more blood vessels. (4) The MVD of middle area of flap of rats in bivalirudin group was (26±5)/mm(2,) significantly higher than that in normal saline group [(18±3)/mm(2,) t=5.43, P<0.05]. (5) The expression of VEGF of middle area of flap of rats in bivalirudin group was 6 534±384, significantly higher than that in normal saline group (4 659±448, t=12.31, P<0.05). Conclusions: Bivalirudin can promote the survival of random skin flap in rats, and the mechanisms may include reducing the formation of thrombosis, improving the blood supply of flap, and increasing the expression of VEGF, promoting the formation of new blood vessels.

Time-to-Event Analysis of Polatuzumab Vedotin-Induced Peripheral Neuropathy to Assist in the Comparison of Clinical Dosing Regimens

Polatuzumab vedotin, an antibody-drug conjugate containing monomethyl auristatin E, was associated with an incidence of grade ≥2 peripheral neuropathy (PN) of 55-72% in patients with indolent non-Hodgkin lymphoma in a phase II study, when dosed 1.8-2.4 mg/kg every 3 weeks until progression or for a maximum of 17 cycles. To quantify the correlation of conjugate exposure and treatment duration with PN risk, a time-to-event model was developed using data from phase I and II studies. The model suggested that PN risk increased with conjugate exposure and treatment cycles, and a trend for increased risk with body weight and albumin concentration. When capping the treatment duration to six to eight cycles, the risk ratio of a dose of 2.4 mg/kg vs. 1.8 mg/kg was ≥1.29; the predicted incidence of grade ≥2 PN at 1.8-2.4 mg/kg dose levels was 17.8-37.2%, which is comparable with other antimicrotubule agents for lymphoma treatment.

Beneficial effects of renal denervation on cardiac angiogenesis in rats with prolonged pressure overload

AIM

Renal denervation (RDN) has beneficial effects on cardiac remodelling and function in resistant hypertension. We aimed to investigate the impact of RDN on cardiac angiogenesis during prolonged pressure overload.

METHODS

Cardiac pressure overload was reproduced by transverse aorta constriction (TAC) procedure in adult Sprague Dawley male rats (n = 35). RDN/sham-RDN procedure was performed in surviving rats at 5 weeks after TAC.

RESULTS

Five weeks post-TAC, transthoracic echocardiography revealed that myocardial hypertrophy occurred in TAC rats, with ejection fraction and fractional shortening not significantly changed. At the end of 10 weeks, cardiac systolic function was preserved in RDN group, but not in sham group. CD31 immunohistochemical staining showed that RDN-treated rats had higher cardiac capillary density than sham rats. However, no significant between-group difference was observed in the kidneys. A decreased protein expression of left ventricle vascular endothelial growth factor (VEGF) was observed in sham group, while RDN attenuated this decrease. Compared with sham, RDN resulted in a higher protein expression of VEGF receptor 2 (VEGFR2) and phosphorylated endothelial nitric oxide synthase (p-eNOS) in the heart.

CONCLUSION

Renal denervation benefits cardiac angiogenesis during sustained pressure overload, involving regulation of VEGF and VEGFR2 expression as well as activation of eNOS.

Searching for large-gap quantum spin hall insulators: boron-nitride/(Pb, Sn)/α-Al2O3 sandwich structures

Topological insulators hold great potential for efficient information processing and storage. Using density functional theory calculations, we predict that a honeycomb lead monolayer can be stabilized on an Al₂O₃ (0001) substrate to become topologically non-trivial with a sizeable band gap (∼0.27 eV). Furthermore, we propose to use a hexagonal boron-nitride (h-BN) monolayer as a protection for the topological states of Pb/Al₂O₃ and Sn/Al₂O₃. Our findings suggest new possibilities for designing and protecting two-dimensional TIs for practical applications.

Abstract P4-22-07: Long-term safety of palbociclib in combination with endocrine therapy in treatment-naive and previously treated women with HR+ HER2– advanced breast cancer: A pooled analysis from randomized phase 2 and 3 studies

Background: Palbociclib (PAL) is a selective and reversible oral cyclin-dependent kinase 4 and 6 inhibitor. Large randomized phase (ph) 2 and 3 trials showed significant improvement in progression-free survival (PFS) when PAL was combined with endocrine therapy (ET) vs ET alone in treatment (trt)-naive and previously treated hormone receptor?positive human epidermal growth factor receptor 2?negative (HR+ HER2–) advanced breast cancer (ABC) patients (pts). The median PFS with PAL+ET is &gt;2 years as a first-line therapy for ABC and 11.2 mo in endocrine-resistant ABC. We evaluated the long-term safety in PALOMA-1, -2, and -3.

Methods: We analyzed the tolerability of PAL in combination with ET in 3 randomized trials. Pts untreated for ABC were randomized to receive PAL+letrozole (LET) vs LET alone in PALOMA-1 (ph 2, open-label; 1:1) or randomized to receive PAL+LET vs placebo (PBO)+LET in PALOMA-2 (ph 3, double-blind; 2:1). PALOMA-3 included pts who progressed on prior ET, randomized to receive PAL+fulvestrant (FUL) or PBO+FUL (ph 3, double-blind; 2:1). Safety assessments, including a complete blood count, were done at baseline, on D1 of each cycle, and on D14 of the first 2 cycles. We evaluated adverse events (AEs) by 6-mo intervals (out to 36 mo) and cumulatively (12-, 24-, and 36-mo time points), and assessed latency (event onset) of pertinent adverse drug reactions (ADRs) in all pts treated in PALOMA-1, -2, and -3.

Results: A total of 1352 pts were pooled for this analysis; 872 pts received PAL+ET (527 pts, PAL+LET; 345 pts, PAL+FUL). Median duration of trt was 421 days in PALOMA-1 (January 2015), 603 days in PALOMA-2 (February 2016), and 330 days in PALOMA-3 (July 2015). PAL+LET was received by 119 pts as first-line trt in PALOMA-1 and 2 for 24–&lt;30 months and 11 pts were treated for &gt;36 mo. PAL+FUL was received by 140 pts for &gt;12 mo as second-line trt in PALOMA-3. The most commonly reported ADRs across all studies were neutropenia, fatigue, nausea, anemia, and leukopenia. The 6-mo-interval analyses of the most common (&gt;15%) AEs (by preferred term [PT]) from PALOMA-1, -2, and -3 indicated that these AEs were reported with the highest frequency during the first 6-mo interval and typically decreased in incidence over time to 30–&lt;36-mo; the most common hematologic AEs (clustered PTs) are shown (Table). The cumulative incidence of AEs after the first vs the second and third years showed similar frequencies of most AEs, including the most common ADRs.

Conclusions: Based on these long-term safety analyses, there is no evidence of specific cumulative or delayed toxicity resulting from prolonged trt with PAL+ET for HR+ HER2– ABC. This supports the ongoing investigation of PAL+ET in early breast cancer (NCT02513394).

Table. Pooled hematologic AEs: all grades and all causality clustered PTs reported for ≥10% of PAL+ET (LET/FUL)-treated ptsTime interval, mo0–&lt;66–&lt;1212–&lt;1818–&lt;2424–&lt;3030–&lt;36≥36Patients, N8726764912891192711TEAEs, %       Neutropenia75.758.649.349.842.937.054.5Leukopenia40.027.416.711.87.611.118.2Anemia20.812.710.011.19.211.118.2Thrombocytopenia15.18.76.15.55.914.836.4TEAEs=treatment-emergent adverse events.

Sponsor: Pfizer.

Citation Format: Diéras V, Rugo HS, Gelmon K, Finn RS, Cristofanilli M, Loi S, Colleoni M, Lu D, Gauthier E, Huang-Bartlett C, Turner NC, Schnell P. Long-term safety of palbociclib in combination with endocrine therapy in treatment-naive and previously treated women with HR+ HER2– advanced breast cancer: A pooled analysis from randomized phase 2 and 3 studies [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-22-07.

Treatment of pediatric forearm midshaft fractures: Is there a difference between types of orthopedic surgeon?

PURPOSE OF THE STUDY

The objective of this study was to compare the clinical and radiological outcomes of pediatric forearm midshaft fractures treated operatively with titanium elastic nails (TENs) by pediatric orthopedists and non-pediatric orthopedists.

MATERIAL AND METHODS

We conducted a prospective cohort study of 88 children of forearm midshaft fractures, who were randomized to operative stabilization either by pediatric orthopedists (Group A, 44 cases) or by non-pediatric orthopedists (Group B, 44 cases) from April 2013 to February 2014. At baseline, the groups were comparable with respect to age, sex, AO classification, injured side and interval from injury to surgery. We collected data on operative and radiation time, open reduction rate, length of hospitalization, bone union time, return to full physical activity time, complications, and measured clinical results using the Children's Hospital of Philadelphia (CHOP) Forearm Fracture Fixation Outcome Classification.

RESULTS

The mean follow-up period was 15.8±3.3 months for Group A and 15.2±4.2 months for Group B (P=0.491). No significant difference existed in time to union (P=0.282), the overall complication rate (P=0.750), return to activity time (P=0.408), and clinical outcomes according to CHOP classification (P=0.908) between the two groups. However, the mean operating time and radiation time was significantly longer in Group B than in Group A (P=0.001 and P=0.001, respectively). In addition, there was a trend for patients of Group B to have a higher rate of open reduction (P=0.035).

DISCUSSIONS

Our results indicated that children forearm midshaft fractures treated surgically by pediatric orthopedists offered potential advantages including a shorter operating time and radiation time, a lower rate of open reduction. However, both pediatric and non-pediatric orthopedists had achieved satisfactory clinical results in treatment of these injuries.

LEVEL OF EVIDENCE

Level II prospective randomized study.