Rhizophagus Irregularis regulates flavonoids metabolism in paper mulberry roots under cadmium stress.

Broussonetia papyrifera is widely found in cadmium (Cd) contaminated areas, with an inherent enhanced flavonoids metabolism and inhibited lignin biosynthesis, colonized by lots of symbiotic fungi, such as arbuscular mycorrhizal fungi (AMF). However, the physiological and molecular mechanisms by which Rhizophagus irregularis, an AM fungus, regulates flavonoids and lignin in B. papyrifera under Cd stress remain unclear. Here, a pot experiment of B. papyrifera inoculated and non-inoculated with R. irregularis under Cd stress was carried out. We determined flavonoids and lignin concentrations in B. papyrifera roots by LC-MS and GC-MS, respectively, and measured the transcriptional levels of flavonoids- or lignin-related genes in B. papyrifera roots, aiming to ascertain the key components of flavonoids or lignin, and key genes regulated by R. irregularis in response to Cd stress. Without R. irregularis, the concentrations of eriodictyol, quercetin and myricetin were significantly increased under Cd stress. The concentrations of eriodictyol and genistein were significantly increased by R. irregularis, while the concentration of rutin was significantly decreased. Total lignin and lignin monomer had no alteration under Cd stress or with R. irregularis inoculation. As for flavonoids- or lignin-related genes, 26 genes were co-regulated by Cd stress and R. irregularis. Among these genes, BpC4H2, BpCHS8 and BpCHI5 were strongly positively associated with eriodictyol, indicating that these three genes participate in eriodictyol biosynthesis and were involved in R. irregularis assisting B. papyrifera to cope with Cd stress. This lays a foundation for further research revealing molecular mechanisms by which R. irregularis regulates flavonoids synthesis to enhance tolerance of B. papyrifera to Cd stress.

[Mercury species analysis and tissue distribution in rats after continuous administration of Cinnabaris].

Cinnabaris is a traditional Chinese medicine(TCM) commonly used for sedation and tranquilization in clinics, and its safety has always been a concern. This study intends to investigate the species and tissue distribution of mercury in rats after continuous administration of Cinnabaris. In the experiment, 30 rats were randomly divided into the control group(equivalent to 0.5% carboxy-methyl cellulose sodium), low-dose Cinnabaris group(0.2 g·kg~(-1)), high-dose Cinnabaris group(2 g·kg~(-1)), pseudogerm-free control group(equivalent to 0.5% sodium carboxymethyl cellulose), and pseudogerm-free Cinnabaris group(2 g·kg~(-1)). They were orally administered for 30 consecutive days. Ultrasound-assisted acid extraction method combined with high performance liquid chromatography and inductively coupled plasma-mass spectrometry(HPLC-ICP-MS) was adopted to determine inorganic mercury [Hg(Ⅱ)], methylmercury(MeHg), and ethylmercury(EtHg) in different tissue, plasma, urine, and feces of rats. The optimal detection conditions and extraction methods were optimized, and the linearity(R~2>0.999 3), precision(RSD<7.0%), and accuracy(spike recoveries ranged from 73.05% to 109.5%) of all the mercury species were satisfied, meeting the requirements of analysis. The results of mercury species detection showed that Hg(Ⅱ) was detected in all the tissue of the five experimental groups, and the main accumulating organs were the intestinal tract, stomach, and kidney. MeHg existed at a low concentration in most tissue, and EtHg was not detected in all groups. In addition, pathological examination results showed that hepatocyte vacuolar degeneration, loose cytoplasm, light staining, and mononuclear cell infiltration were observed in the high-dose Cinnabaris group, low-dose Cinnabaris group, and pseudogerm-free Cinnabaris group, with slightly milder lesions in the low-dose Cinnabaris group. Hydrous degeneration of renal tubular epithelium could be seen in the high-dose Cinnabaris group and pseudogerm-free Cinnabaris group, but there was no significant difference between the other groups and the control group. No abnormal changes were found in the brain tissue of rats in each group. This paper studied the different mercury species and tissue distribution in normal and pseudogerm-free rats after continuous administration of Cinnabaris for 30 days and clarified its effects on the tissue structure of the liver, kidney, and brain, which provided supporting evidence for the safety evaluation of Cinnabaris.

IL-27 deficiency inhibits proliferation and invasion of trophoblasts via the SFRP2/Wnt/ß-catenin pathway in fetal growth restriction.

Background: Fetal growth restriction (FGR) is characterized by restricted fetal growth and dysregulated placental development. The etiology and pathogenesis still remain elusive. IL-27 shows multiple roles in regulating various biological processes, however, how IL-27 involves in placentation in FGR pregnancy hasn't been demonstrated. Methods: The levels of IL-27 and IL-27RA in FGR and normal placentae were determined by immunohistochemistry, western blot and RT-PCR. HTR-8/SVneo cells and Il27ra-/- murine models have been adopted to evaluate the effects of IL-27 on the bio-functions of trophoblast cells. GO enrichment and GSEA analysis were performed to explore the underlying mechanism. Findings: IL-27 and IL-27RA was lowly expressed in FGR placentae and administration of IL-27 on HTR-8/SVneo could promote its proliferation, migration and invasion. Comparing with wildtypes, Il27ra-/- embryos were smaller and lighter, and the placentae from which were poorly developed. In mechanism, the molecules of canonical Wnt/ß-catenin pathway (CCND1, CMYC, SOX9) were downregulated in Il27ra-/- placentae. In contrast, the expression of SFRP2 (negative regulator of Wnt) was increased. Overexpression of SFRP2 in vitro could impair trophoblast migration and invasion capacity. Interpretation: IL-27/IL-27RA negatively regulates SFRP2 to activate Wnt/ß-catenin, and thus promotes migration and invasion of trophoblasts during pregnancy. However, IL-27 deficiency may contribute to the development of FGR by restricting the Wnt activity.

Morphological Changes of Medial Epicondyle-Olecranon Ligament and Ulnar Nerve in the Cubital Tunnel Syndrome: An Ultrasonic Study.

OBJECTIVE: Few studies have performed detailed ultrasound measurements of medial epicondyle-olecranon (MEO) ligament that cause the entrapment of ulnar nerve. This study aims to comprehensively evaluate dynamic ultrasonographic characteristics of MEO ligament and ulnar nerve for clinical diagnosis and accurate treatment of cubital tunnel syndrome (CuTS). METHODS: Thirty CuTS patients (CuTS group) and sixteen healthy volunteers (control group) who underwent ultrasound scanning from October 2016 to October 2020 were retrospectively collected, with 30 elbows in each group. Primary outcomes were thickness at six points, length and width of MEO ligament. Secondary outcomes were thickness of ulnar nerve under MEO ligament at seven parts and the cross-sectional area (CSA) of ulnar nerve at proximal end of MEO ligament (P0 mm ). The thickness of MEO ligament and ulnar nerve in different points of each group was compared by one-way ANOVA analysis with Bonferroni post hoc test, other outcomes were compared between two elbow positions or two groups using independent-samples t test. RESULTS: Thickness of MEO ligament in CuTS group at epicondyle end, midpoint in transverse view, olecranon end, proximal end, midpoint in axial view, and distal end was 0.67 ± 0.31, 0.37 ± 0.18, 0.89 ± 0.35, 0.39 ± 0.21, 0.51 ± 0.38, 0.36 ± 0.25 at elbow extension, 0.68 ± 0.34, 0.38 ± 0.27, 0.77 ± 0.39, 0.32 ± 0.20, 0.48 ± 0.22, 0.32 ± 0.12 (mm) at elbow flexion, respectively. Compared with control group, they were significantly thickened except for proximal end at elbow flexion. MEO ligament thickness at epicondyle end and olecranon end was significantly larger than midpoint in two groups. No significant difference was found in length and width of MEO ligament among different comparisons. Ulnar nerve thickness at 5 mm proximal to MEO ligament (P5 mm , 3.25 ± 0.66 mm) was significantly increased than midpoint of MEO ligament (Mid), distal end of MEO ligament (D0 mm ), 5 mm (D5 mm ), 10 mm (D10 mm ) distal to MEO ligament at extension in CuTS group. Compared with control group, ulnar nerve thickness at P5 mm in CuTS group was significantly increased at extension position, at D5 mm and D10 mm was significantly decreased at flexion position. CSA of ulnar nerve at extension position (14.44 ± 4.65 mm2 ) was significantly larger than flexion position (11.83 ± 3.66 mm2 ) in CuTS group, and CuTS group was significantly larger than control group at two positions. CONCLUSIONS: MEO ligament in CuTS patients was thickened, which compressed ulnar nerve and caused its proximal end swelling. Ultrasonic image of MEO ligament thickness was a significant indicator for CuTS and can guide surgeons in selecting the appropriate treatment.

[Dynamic monitoring and evaluation of ecological environment quality in Zhouqu County, Gansu, China based on Google Earth Engine cloud platform]. / 基于Google Earth Engine云平台的甘肃舟曲县生态环境质量动态监测与评价.

Zhouqu County is located in the transition region from the Qinghai-Tibet Plateau to the Qinba Mountains, and is an important part of the ecological barrier in the upper stream of the Yangtze River. In this study, we used the Google Earth Engine cloud processing platform to perform inter-image optimal reconstruction of Landsat surface reflectance images from 1998-2019. We calculated four indicators of regional wet, green, dry, and hot. The component indicators were coupled by principal component analysis to construct remote sensing ecological index (RSEI) and to analyze the spatial and temporal variations of ecological environment quality in Zhouqu County. The results showed that the contribution of the four component indicators to the eigenvalues of the coupled RSEI were above 70%, with even distribution of the loadings, indicating that the RSEI integrated most of the features of the component indicators. From 1998 to 2019, the RSEI of Zhouqu County ranged from 0.55 to 0.63, showing an increasing trend with a growth rate of 0.04·(10 a)-1, and the area of better grade increased by 425.56 km2. The area with altitude ≤2200 m was dominated by medium and lower ecological environment quality grade, while the area of better ecological environment quality grade area increased by 16.5%. The ecological and environmental quality of the region from 2200 to 3300 m was dominated by good grades, increasing to 71.3% in 2019, with the area of medium and below ecological and environmental quality grades decreasing year by year. The area with altitude ≥3300 m was dominated by the medium ecological quality grade. The medium and below ecological quality grades showed a "U" shape trend during the study period. The trend of ecological environment quality in Zhouqu County was becoming better, but with fluctuations. It is necessary to continuously strengthen the protection and management of ecological environment in order to guarantee the continuous improvement of ecological environment quality.

A real-time multi-function digital coincidence spectrometer for neutron copper activation diagnostics.

Copper activation has been a standard diagnostic for measuring 14.1-MeV neutron yields in deuterium-tritium fusion experiments, which is essential to evaluate their performance for potential ignition in the future. Copper-activation equipment, especially data-acquisition systems, is updated constantly thanks to the rapid developments in electronics. Here, a multi-function digital coincidence spectrometer for neutron copper-activation diagnostics was developed. The digital pulse processing includes pulse shaping, multichannel pulse analysis, coincidence event picks, and coincidence multichannel time analysis were implemented on a single field-programmable gate array (FPGA) chip. The results demonstrate that the coincidence background is 0.013 counts per second. By using the multi-function digital coincidence spectrometer, the copper-activation diagnostics could be performed at the SG-III Laser facility when the neutron yield is ≥ 1.0 × 1010/hit.

[Functional traits of leaves with different ages of Taxus wallichiana var. chinensis saplings.] / çº¢è±†æ‰å¹¼æ ‘å¼‚é¾„å¶çš„åŠŸèƒ½æ€§çŠ¶.

Variations of functional traits with leaf age reflect plant life history strategy and indicate allocation pattern and trade-off characteristics in the limiting resource. In this study, leaves with different ages of Taxus wallichiana var. chinensis saplings were taken as experimental materials. Fourteen leaf functional traits of leaves at three differebt ages were measured in order to reveal changes of the saplings' ecological strategies with leaf aging. The results showed that one-year-old leaves had significantly higher specific leaf area than two- and three-year-old lea-ves, while three-year-old leaves had significantly greater leaf thickness, leaf area, volume, fresh weight and dry weight than leaves at other ages. In addition, one-year-old leaves had significantly greater nitrogen content (N), phosphorus content (P) and N:P than two- and three-year-old leaves, but lower C:N than three-old-year leaves. The slope of allometric relationship between leaf water content and dry weight, leaf thickness and leaf area of one-year-old leaves, leaf thickness and leaf area of three-year-old leaves were all significantly lower than 1.0. Two-year-old leaves showed significantly allometric relationships between many leaf traits, with slope being not equal to 1.0. In conclusion, one-year-old leaves of T. wallichiana var. chinensis saplings tended to have higher photosynthetic capacity, two-year-old leaves had stronger dry matter accumulation, and three-year-old leaves would construct defense system. The coordination and complementation of functional traits among leaves with different ages might have great significance for maintaining individual homeostasis and survival.

Ultrasound-Assisted Precise In Situ Decompression for Cubital Tunnel Syndrome.

OBJECTIVE: To explore the effect of locating the ulnar nerve compression sites and guiding the small incision so as to decompress the ulnar nerve in situ on the elbow by high-frequency ultrasound before operation. METHODS: A retrospective analysis was conducted on 56 patients who underwent ultrasound-assisted in situ decompression for cubital tunnel syndrome from May 2018 to August 2019. The patients' average age was 51.13 ± 7.35 years, mean duration of symptoms was 6.51 ± 1.96 months, and mean postoperative follow-up was 6.07 ± 0.82 months. Nine patients had Dellon's stage mild, 39 had stage moderate, and eight had stage severe. Ultrasound and electromyography were completed in all patients before operation. The presence of ulnar nerve compressive lesion, the specific location, and the reason and extent of compression were determined by ultrasound. A small incision in situ surgery was given to decompress the ulnar nerve according to the pre-defined compressive sites. RESULTS: All patients underwent in situ decompression. The compression sites around the elbow were as follows: two in the arcade of Struthers, one in the medial intermuscular septum, four in the anconeus epitrochlearis muscle, five beside the cyst of the proximal flexor carpi ulnaris (FCU), and the remaining 44 cases were all from the compression between Osborne's ligament to the two heads of the FCU. The compression localizations diagnosed by ultrasound were confirmed by operations. Preoperative ultrasound confirmed no ulnar nerve subluxation in all cases. The postoperative outcomes were satisfactory. There was no recurrence or aggravation of symptoms in this group of patients according to the modified Bishop scoring system; results showed that 43 cases were excellent, 10 were good, and three were fair. CONCLUSIONS: High-frequency ultrasound can accurately and comprehensively evaluate the ulnar nerve compression and the surrounding tissues, thus providing significant guidance for the precise minimally invasive treatment of ulnar nerve compression.

Angiography and transcatheter arterial embolization for non-variceal gastrointestinal bleeding.

BACKGROUND AND GOALS: Acute non-variceal gastrointestinal bleeding (NVGIB) is one of the most common medical emergencies, leading to significant morbidity and mortality without proper management. This study was to analyze the causes of NVGIB and to evaluate the safety, efficacy, and feasibility of transcatheter arterial embolization (TAE) for the treatment of NVGIB. STUDY: From November 2012 to October 2018, 158 patients with NVGIB underwent digital subtraction angiography, and TAE was performed for confirmed gastrointestinal bleeding. Patient characteristics, cause of bleeding, angiographic findings, technical and clinical success rates, complication rates, and outcomes were retrospectively analyzed. RESULTS: Bleeding was confirmed in 71.5% (113/158) of performed angiographies, and 68 patients had visible contrast extravasation on angiography, with the other 45 patients having indirect signs of bleeding. Among the 113 patients with confirmed gastrointestinal bleeding, TAE was technically successful in 111 patients (98.2%). The mean procedure time required for TAE was 116 ± 44 min (ranging from 50 to 225 min). The primary total clinical success rate of TAE was 84.7% (94/111). The primary clinical success rates of TAE for vascular abnormality, neoplastic disease, and iatrogenic condition were 84.5% (49/58), 84.1% (37/44), and 88.9% (8/9), respectively. Intestinal necrosis and perforation were found in two patients after TAE. CONCLUSIONS: The causes of NVGIB are complex and the onset, location, risk, and clinical presentations are variable. NVGIB can be generally divided into three types: vascular abnormality, neoplastic disease, and iatrogenic condition. TAE is a safe, effective, and fast procedure in the management of gastrointestinal bleeding.

Cardiac autonomic function test in children with vasovagal syncope / 国际儿科学杂志

Vasovagal syncope(VVS)is a chronic recurrent disease.It is the most common cause of syncope in child and adolescents, accounting for 45%~60% of all syncopal cases.Repeated episodes of syncope severely affect the learning of children and adolescents and the quality of life of their families, which has attracted great attention from clinicians.The pathogenesis of VVS has not been clarified, and it is currently thought to be mainly related to autonomic dysfunction.Therefore, examining and evaluating cardiac autonomic function can help to diagnose VVS and prevent syncope.This article reviews the cardiac autonomic tests such as heart rate variability, QT dispersion and P wave dispersion, heart rate deceleration capacity and heart rate deceleration runs, 24-hour ambulatory blood pressure monitoring, and post-exercise heart rate recovery to explore its effectiveness in the diagnosis of VVS in children.

Outcomes of Surgical Management of Neurogenic Thoracic Outlet Syndrome: A Systematic Review and Bayesian Perspective.

PURPOSE: To provide a summary of the relevant evidence on outcomes of transaxillary first rib excision (TAFRE), supraclavicular first rib excision with scalenectomy (SCFRE), and supraclavicular release leaving the first rib intact (SCR) for patients with neurogenic thoracic outlet syndrome (TOS), and interpret the treatment effects from a Bayesian perspective. METHODS: A systematic literature search and review were performed. Random-effects meta-analyses were conducted to estimate success rate and complete relief rate of each procedure. The probabilities of specified success rates and complete relief rates were calculated using a Bayesian method. Sensitivity analyses for TOS type, neck trauma, and cervical rib were performed. Complications of each procedure were also reviewed. RESULTS: Data were extracted from 17 studies of TAFRE, 9 of SCFRE, and 14 of SCR to conduct the meta-analyses. The pooled success rate and complete relief rate were 0.76 (95% confidence interval [95% CI)], 0.65-0.85) and 0.53 (95% CI, 0.38-0.68) for TAFRE, 0.77 (95% CI, 0.68-0.85) and 0.57 (95% CI, 0.41-0.72) for SCFRE, and 0.85 (95% CI, 0.76-0.92) and 0.61 (95% CI, 0.35-0.84) for SCR, respectively. The probabilities of success rate greater than 70% were 90%, 87%, and 99% for TAFRE, SCFRE, and SCR, respectively. If the success rate of 80% or greater was considered, the probabilities were 34%, 31%, and 91%, respectively. The probabilities of complete relief rate of 50% or greater were 67%, 71%, and 69% for TAFRE, SCFRE, and SCR, respectively. Sensitivity analyses showed similar results. The complication rates for TAFRE, SCFRE, and SCR were, respectively, 22.5%, 25.9%, and 12.6%. CONCLUSIONS: The SCR has a high probability of success rate greater than 80%; both TAFRE and SCFRE have high probabilities of a success rate greater than 70% but only low probabilities of success rate greater than 80%. The TAFRE and SCFRE have more complications than SCR. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Wide-Awake Hand Surgery in Two Centers in China: Experience in Nantong and Tianjin with 12,000 patients.

This article summarizes the application of local anesthesia no tourniquet in 2 hand surgery centers in China, Nantong and Tianjin, where more than 12,000 patients were operated on with the new approach. This approach achieves excellent anesthetic and vasoconstrictive effects. In Nantong, surgeons performed fracture fixation, soft tissue tumor excision, and flap transfer in the hand with this approach. In Tianjin, surgeons applied it to cases of hand trauma emergency surgery. The authors' experience shows that this approach to hand surgery is safe, economical, and patient friendly, with no increase in infection rate.

Catheter Embolization of Type II Congenital Extrahepatic Portosystemic Shunt with Hematochezia: A Case Series and Review of the Literature.

Hematochezia is a rare clinical presentation of congenital extrahepatic portosystemic shunt (CEPS). We describe a series of three patients with type II CEPS presenting as hematochezia that were treated by catheter embolization, followed by a brief review of published articles. Hematochezia of the patients was due to the giant inferior mesenteric vein, superior rectal vein and colonic varices. The catheter embolization was successfully accomplished in all of the patients. After a mean follow-up of 27 months, no serious adverse effects were observed. For unexplained massive hematochezia, CEPS needs to be considered as a differential diagnosis. Based on our present results and the review of the literature, transcatheter permanent embolization of the giant inferior mesenteric vein might be an effective and safe treatment for type II CEPS.Level of Evidence Level 4, case series.

Safety and Feasibility of Temporary Superior Vena Cava Filter Combined with Balloon Dilatation and Catheter-Directed Thrombolysis for Catheter-Related Thrombosis.

BACKGROUND: The objective was to evaluate the safety and feasibility of temporary superior vena cava (SVC) filter combined with balloon dilatation and catheter-directed thrombolysis for the treatment of catheter-related thrombosis (CRT) caused by implanted ports. METHODS: Between February 2014 and October 2016, 13 patients with implanted port-related CRT in internal jugular vein, brachiocephalic vein, and/or subclavian vein were treated by temporary SVC filter, balloon dilatation, and catheter-directed thrombolysis. Clinical data were retrospectively analyzed with respect to clinical characteristics, SVC filter placement and retrieval, balloon dilatation, and catheter-directed thrombolysis. RESULTS: Filter placement and retrieval, balloon dilatation, and catheter-directed thrombolysis were successful in all patients with complete patency of the suffered vessels. No complications such as local infection, filter migration, bleeding, and pulmonary embolism were found. CONCLUSIONS: Based on the small number of patients, it appears that temporary SVC filter combined with balloon dilatation and catheter-directed thrombolysis is a safe and effective method for the treatment of CRT associated with malfunction of the implanted ports and complete obstruction of affected veins. Further studies are required to demonstrate the cost-effectiveness and complications compared to conventional therapy.

Manipulative reduction and plaster external fixation for the treatment of the scaphoid fracture and perilunate dislocation / 中国骨伤

<p><b>OBJECTIVE</b>To investigate the efficacy and complications of manual reduction and external fixation for the treatment of scaphoid fractures and perilunate dislocations.</p><p><b>METHODS</b>From January 2009 to January 2013, 43 patients suffered from scaphoid fractures and perilunate dislocations were retrospective analyzed. Among them, 17 cases were treated with manipulative reduction and plaster external fixation as conservation group including 10 males and 7 females, the other 26 cases were treated with application of surgical as operation group including 15 males and 11 females. The clinical effects were assessed by Cooney function score, radiological analysis and observation of complications.</p><p><b>RESULTS</b>All patients were followed up for(45.00±8.72) months ranging from 36 to 60 months. At the final follow-up, the Cooney score of wrist function was 88.53±4.24 in conservation group and 89.58±4.59in operation group(0.455, >0.05). During the follow-up, 4 patients were found scaphoid avascular necrosis in the imaging performance in the conservation group(χ²=4.32, <0.05). The difference of other complications between two groups was not statistically significant(>0.05).</p><p><b>CONCLUSIONS</b>For patients suffered from the scaphoid fractures and perilunate dislocation, the early manipulative reduction and plaster external fixation after injury as soon as possible is necessary. Maintaining a satisfactory reduction and reliable fixation at the same time can lead to good treatment effect and there's no weakness compared to surgical treatment. But there was an increase in danger of complications. The key of conservative treatment lies in early diagnosis and maintenance of reduction, reliable fixation, and timely and appropriate functional exercise.</p>

Performing Hand Surgery Under Local Anesthesia Without a Tourniquet in China.

In China, wide-awake surgeries are increasingly used by surgeons in a growing number of hospitals for hand and upper extremity surgeries. Experience suggests that wide-awake surgery is safe, economical, and patient-friendly, optimizing hospital resource allocation and increasing efficiency. This article discusses which procedures are most suitable, variations in procedures, departmental impacts, and future direction.

Strong Digital Flexor Tendon Repair, Extension-Flexion Test, and Early Active Flexion: Experience in 300 Tendons.

Over the past 2 decades, repair and rehabilitation methods of primary repair of the digital flexor tendon have changed. In this article, we outline interim results from ongoing investigations in several units. Surgeons in these units now perform digital flexor tendon repairs according to a treatment protocol. Before adopting the protocol, they had no history of tendon-related research; they had not used any of the repair and rehabilitation methods described in the protocol. The surgeons involved are junior or midlevel attending surgeons. At the end of this article, we outline current practice of digital flexor tendon repair in Asian countries.

Cost-Effectiveness of Diagnostic Strategies for Suspected Scaphoid Fractures.

OBJECTIVES: The aim of this study was to assess the cost effectiveness of multiple competing diagnostic strategies for suspected scaphoid fractures. METHODS: With published data, the authors created a decision-tree model simulating the diagnosis of suspected scaphoid fractures. Clinical outcomes, costs, and cost effectiveness of immediate computed tomography (CT), day 3 magnetic resonance imaging (MRI), day 3 bone scan, week 2 radiographs alone, week 2 radiographs-CT, week 2 radiographs-MRI, week 2 radiographs-bone scan, and immediate MRI were evaluated. The primary clinical outcome was the detection of scaphoid fractures. The authors adopted societal perspective, including both the costs of healthcare and the cost of lost productivity. The incremental cost-effectiveness ratio (ICER), which expresses the incremental cost per incremental scaphoid fracture detected using a strategy, was calculated to compare these diagnostic strategies. Base case analysis, 1-way sensitivity analyses, and "worst case scenario" and "best case scenario" sensitivity analyses were performed. RESULTS: In the base case, the average cost per scaphoid fracture detected with immediate CT was $2553. The ICER of immediate MRI and day 3 MRI compared with immediate CT was $7483 and $32,000 per scaphoid fracture detected, respectively. The ICER of week 2 radiographs-MRI was around $170,000. Day 3 bone scan, week 2 radiographs alone, week 2 radiographs-CT, and week 2 radiographs-bone scan strategy were dominated or extendedly dominated by MRI strategies. The results were generally robust in multiple sensitivity analyses. CONCLUSIONS: Immediate CT and MRI were the most cost-effective strategies for diagnosing suspected scaphoid fractures. LEVEL OF EVIDENCE: Economic and Decision Analyses Level II. See Instructions for Authors for a complete description of levels of evidence.