Survey of Bacterial Phylogenetic Diversity During the Glacier Melting Season in an Arctic Fjord.

To understand bacterial biogeography in response to the hydrographic impact of climate change derived from the Arctic glacier melting, we surveyed bacterial diversity and community composition using bacterial 16S rRNA gene metabarcoding in the seawaters of Kongsfjorden, Svalbard, during summer 2016. In the present study, bacterial biogeography in the Kongsfjorden seawaters showed distinct habitat patterns according to water mass classification and habitat transition between Atlantic and fjord surface waters. Moreover, we estimated phylogenetic diversity of bacterial communities using the net relatedness, nearest taxon, and beta nearest taxon indices. We found the influence of freshwater input from glacier melting in shaping bacterial assemblage composition through the stochastic model. We further evaluated bacterial contributions to phytoplankton-derived dimethylsulfoniopropionate (DMSP) using a quantitative PCR (qPCR) measurement with demethylation (dmdA) and cleavage (dddP) genes of two fundamentally different processes. Our qPCR results imply that bacterial DMSP degradation follows the Atlantic inflow during summer in Kongsfjorden. These findings suggest that the Atlantic inflow and glacial melting influence bacterial community composition and assembly processes and thus affect the degradation of phytoplankton-derived organic matter in an Arctic fjord.

Analysis of swine fecal microbiota at various growth stages.

Recent obesity studies in humans and rodents have suggested that host weight gain is significantly associated with energy harvesting efficiency which is regulated by gut microbiota. Antibiotic growth promoters have been banned as feed additives in many countries. In this study, we aimed to provide knowledge of swine fecal microbiota by analyzing bacterial 16S rRNA gene sequences. Our results showed that swine fecal bacterial composition varied at each growth stage. Bacteroidetes decreased as the swine gained weight and unclassified genera significantly increased at later growth stages. Operational taxonomic unit (OTU) distribution analysis showed that the bacterial community difference was most significant between growers and finishers, while analysis of shared OTUs indicated a greater proportion of common species between growers and finishers. The differential abundance test between growers and finishers detected that nearly half of the species were shared OTUs, suggesting that differential abundance of each bacterial species predominantly controls bacterial community differences. Although functions of these bacteria are yet to be identified, understanding differences in fecal microbiota between each growth stage will provide additional insights for further studies related to swine gut microbiota.

Lateral meniscocapsular separation in patients with tibial plateau fractures: detection with magnetic resonance imaging.

OBJECTIVE: This study aimed to retrospectively evaluate magnetic resonance imaging findings for the detection of lateral meniscocapsular separation (LMCS) in patients with tibial plateau fractures. We hypothesize that patients with LMCS have greater perimeniscal abnormal signal or greater distance between the lateral meniscus (LM) and the lateral collateral ligament (LCL) than patients without LMCS. METHODS: The study group included 16 patients with LMCS and 11 patients with normal LMCS who underwent surgery due to tibial plateau fracture. Magnetic resonance images were assessed for the width of perimeniscal abnormal signals on 3 orthogonal planes. The distance between LM and LCL was measured on coronal images. Nonparametric tests were performed. RESULTS: The thickness of perimeniscal abnormal signals was increased in the patient group than in control group (median, 10.00 [interquartile range, 9.00-12.70] mm vs 3.39 [2.45-3.67] mm at axial images [P < 0.001]; 8.60 [3.75-11.26] mm vs 2.73 [1.64-4.38] mm at coronal images [P = 0.015]; 13.57 [9.50-15.04] mm vs 4.65 [0-5.89] mm at sagittal images [P = 0.002], respectively). Sixteen patients in the patient group had involvement around the whole LM, whereas none of the patients in the control group had involvement around the whole LM (P < 0.001). The distance between LM and LCL was increased in the patient group than in the control group (9.00 [7.47-10.75] mm vs 5.11 [4.38-7.07] mm [P = 0.002], respectively). The cutoff value of 7 mm thickness of abnormal signal and distance between LM and LCL showed an accuracy of 96% (26/27 patients) and 85% (23/27 patients), respectively. CONCLUSIONS: Patients with perimeniscal signal greater than 7 mm or distance between LM and LCL greater than 7 mm have high likelihood of LMCS.

Learning curve of office-based ultrasonography for rotator cuff tendons tears.

PURPOSE: To compare the accuracy of ultrasonography and MR arthrography (MRA) imaging in detecting of rotator cuff tears with arthroscopic finding used as the reference standard. METHODS: The ultrasonography and MRA findings of 51 shoulders that underwent the arthroscopic surgery were prospectively analysed. Two orthopaedic doctors independently performed ultrasonography and interpreted the findings at the office. The tear size measured at ultrasonography and MRA was compared with the size measured at surgery using Pearson correlation coefficients (r). The sensitivity, specificity, accuracy, positive predictive value, negative predictive value and false-positive rate were calculated for a diagnosis of partial-and full-thickness rotator cuff tears. The kappa coefficient was calculated to verify the inter-observer agreement. RESULTS: The sensitivity of ultrasonography and MRA for detecting partial-thickness tears was 45.5 and 72.7 %, and that for full-thickness tears was 80.0 and 100 %, respectively. The accuracy of ultrasonograpy and MRA for detecting partial-thickness tears was 45.1 and 88.2 %, and that for full-thickness tears was 82.4 and 98 %, respectively. Tear size measured based on ultrasonography examination showed a poor correlation with the size measured at arthroscopic surgery (r = 0.21; p < 0.05). However, tear size estimated by MRA showed a strong correlation (r = 0.75; p < 0.05). The kappa coefficient was 0.47 between the two independent examiners. CONCLUSIONS: The accuracy of office-based ultrasonography for beginner orthopaedic surgeons to detect full-thickness rotator cuff tears was comparable to that of MRA but was less accurate for detecting partial-thickness tears and torn size measurement. Inter-observer agreement on the interpretation was fair. These results highlight the importance of the correct technique and experience in operation of ultrasonography in shoulder joint. LEVEL OF EVIDENCE: Diagnostic study, Level II.

Meniscal tear configurations: categorization with 3D isotropic turbo spin-echo MRI compared with conventional MRI at 3 T.

OBJECTIVE: The purpose of our study was to compare the accuracy of 3D fat-suppressed isotropic turbo spin-echo (TSE) sequences using sampling perfection with application-optimized contrasts using different flip angle evolution (SPACE) with 2D conventional MRI at 3 T in determining meniscal tear types. MATERIALS AND METHODS: Sixty-nine patients with arthroscopically confirmed meniscal tears underwent MRI with 2D sequences and 3D TSE SPACE. Images were retrospectively analyzed by two reviewers and correlated with arthroscopic findings. Meniscal tears were classified into one of eight types: horizontal, longitudinal, radial, root, flap, oblique, complex, and bucket-handle. For every type of tear, sensitivity, specificity, and interobserver agreement were calculated. RESULTS: Mean sensitivities and specificities on 3D TSE SPACE versus 2D sequences were as follows: for radial tears, 77% and 93% versus 68% and 90%; for flap tears, 73% and 96% versus 54% and 85%; for horizontal tears, 85% and 91% versus 78% versus 87%; for longitudinal tears, 50% and 97% versus 72% and 96%; and for root tears, 88% and 99% versus 81% and 99%. The specificity for flap tears was statistically higher on 3D TSE SPACE than 2D sequences. Interobserver agreements were higher on 3D TSE SPACE than 2D sequences for radial, flap, and longitudinal tears. CONCLUSION: In categorizing meniscal tears, 3D TSE SPACE has higher specificity for flap tears than 2D conventional sequences. However, there is no significant difference between 2D conventional sequences and 3D TSE SPACE except for flap tears.

Estimation of maximal oxygen uptake without exercise testing in Korean healthy adult workers.

Maximal oxygen uptake is generally accepted as the most valid and reliable index of cardiorespiratory fitness and functional aerobic capacity. The exercise test for measuring maximal oxygen uptake is unsuitable for screening tests in public heath examinations, because of the potential risks of exercise exertion and time demands. We designed this study to determine whether work-related physical activity is a potential predictor of maximal oxygen uptake, and to develop a maximal oxygen uptake equation using a non-exercise regression model for the cardiorespiratory fitness test in Korean adult workers. Study subjects were adult workers of small-sized companies in Korea. Subjects with history of disease such as hypertension, diabetes, asthma and angina were excluded. In total, 217 adult subjects (113 men of 21-55 years old and 104 women of 20-64 years old) were included. Self-report questionnaire survey was conducted on study subjects, and maximal oxygen uptake of each subject was measured with the exercise test. The statistical analysis was carried out to develop an equation for estimating maximal oxygen uptake. The predictors for estimating maximal oxygen uptake included age, gender, body mass index, smoking, leisure-time physical activity and the factors representing work-related physical activity. The work-related physical activity was identified to be a predictor of maximal oxygen uptake. Moreover, the equation showed high validity according to the statistical analysis. The equation for estimating maximal oxygen uptake developed in the present study could be used as a screening test for assessing cardiorespiratory fitness in Korean adult workers.

A new technique of arthroscopic fixation using double anchors for SLAP lesions.

PURPOSE: The aim of this study was to evaluate the clinical and structural outcome of the new fixation technique of type-II SLAP repair using double anchors compared with conventional method. METHODS: Twenty-eight patients with 29 shoulders, who were followed up for at least 1 year after surgery, were enrolled. Fourteen shoulders were treated using the new technique (group 1), and 15 shoulders using the conventional technique (group 2). The clinical outcomes were evaluated using two different functional scores, the pain VAS and range of motion. The postoperative labral integrity was determined by magnetic resonance imaging at 1 year after surgery. RESULTS: At postoperative 6 months, all functional scores of group 1 were superior to group 2, particularly in pain VAS and Constant Scoring System. All ranges of motion in group 1 showed a better result than in group 2, particularly in forward flexion and external rotation at 90° abduction (88° ± 4.8 in group 1 and 84° ± 9.2 in group 2, P = 0.03). At postoperative 12 months and the last visit, all functional scores in group 1 were superior to those in group 2 and all external rotations at 90° of abduction in group 1 showed significantly better results than those of group 2. All patients in group 1 showed complete healing of the repaired SLAP lesion but one patient in group 2 showed partial detachments on the MRI. CONCLUSIONS: This new technique provides anatomical restoration of a SLAP lesion and yields successful clinical and structural outcomes at a short-term follow-up. LEVEL OF EVIDENCE: Randomized controlled trials, level II.

Proton density-weighted MR imaging of the knee: fat suppression versus without fat suppression.

OBJECTIVE: To prospectively evaluate the diagnostic accuracy of proton density-weighted imaging with and without fat suppression for detecting meniscal tears. MATERIALS AND METHODS: The study involved 48 patients who underwent arthroscopy less than 3 months after proton density-weighted imaging with and without fat suppression. Sagittal images were independently reviewed by two radiologists for the presence of meniscal tears. Medial and lateral menisci were separately analyzed in terms of anterior horn, body, and posterior horn. Interobserver agreement was assessed using κ coefficients. The McNemar test was used to determine any differences between the two methods in terms of sensitivity and specificity. Arthroscopy findings were used as the diagnostic reference standard. RESULTS: Arthroscopy revealed 71 tears involving 85 meniscal segments: 34 medial meniscal segments and 51 lateral meniscal segments. The sensitivity, specificity, and accuracy of each radiologist were 95% (81/85), 92% (186/203), and 93% (267/288), and 93% (79/85), 93% (189/203), and 93% (268/288) when using fat-suppressed proton density-weighted imaging, and 91% (77/85), 93% (189/203), and 92% (266/288), and 91% (77/85), 93% (188/203), and 92% (265/288) when using proton density-weighted imaging without fat suppression, respectively. Interobserver agreement for meniscal tears was very high with proton-weighted imaging with (κ = 0.87) or without (κ = 0.86) fat suppression. There were no significant differences for detection of medial meniscal tears when using proton density-weighted imaging with or without fat suppression for both readers (p > 0.05). CONCLUSION: Fat-suppressed proton density-weighted imaging can replace proton density-weighted imaging without fat suppression for the detection of meniscal tears.

Microbial source tracking using metagenomics and other new technologies.

The environment is under siege from a variety of pollution sources. Fecal pollution is especially harmful as it disperses pathogenic bacteria into waterways. Unraveling origins of mixed sources of fecal bacteria is difficult and microbial source tracking (MST) in complex environments is still a daunting task. Despite the challenges, the need for answers far outweighs the difficulties experienced. Advancements in qPCR and next generation sequencing (NGS) technologies have shifted the traditional culture-based MST approaches towards culture independent technologies, where community-based MST is becoming a method of choice. Metagenomic tools may be useful to overcome some of the limitations of community-based MST methods as they can give deep insight into identifying host specific fecal markers and their association with different environments. Adoption of machine learning (ML) algorithms, along with the metagenomic based MST approaches, will also provide a statistically robust and automated platform. To compliment that, ML-based approaches provide accurate optimization of resources. With the successful application of ML based models in disease prediction, outbreak investigation and medicine prescription, it would be possible that these methods would serve as a better surrogate of traditional MST approaches in future.

Fish farm effluents as a source of antibiotic resistance gene dissemination on Jeju Island, South Korea.

The abuse or misuse of antibiotics is directly linked to the emergence of antibiotic-resistant bacteria and antibiotic resistance genes (ARGs) in the environment. Most fish farms located on Jeju Island operate a flow-through system that pumps in seawater for fish farming and discharges it back to the ocean. To investigate the amount of ARGs that these fish farm effluents discharge into the marine environment, we conducted a metagenomic-based resistome analysis. We observed higher levels of ARGs in fish farm effluents than in seawater at beach and residential areas. A greater proportion of ARGs was found on plasmid rather than on chromosomal DNA, especially for sulfonamide and phenicol classes. The distribution of ARGs did not differ between summer and winter, but the microbial community did. In addition, fish farm samples contained significantly more opportunistic pathogens (i.e., Vibrio, Photobacterium, Aliivibrio, and Tenacibaculum) and virulence factors than non-fish farm samples. Vibrio was the most frequently identified host of ARGs and virulence factors. The presence of Vibrio in the coastal area has been increasing owing to the recent rise in the temperature of seawater. This study suggests the need for actions to treat or monitor ARGs in the coastal areas where fish farms operating a flow-through system are located.

A hybrid DNA sequencing approach is needed to properly link genotype to phenotype in multi-drug resistant bacteria.

Antibiotic resistance genes (ARGs) are now viewed as emerging contaminants posing a potential worldwide human health risk. The degree to which ARGs are transferred to other bacteria via mobile genetic elements (MGEs), including insertion sequences (ISs), plasmids, and phages, has a strong association with their likelihood to function as resistance transfer determinants. Consequently, understanding the structure and function of MGEs is paramount to assessing future health risks associated with ARGs in an environment subjected to strong antibiotic pressure. In this study we used whole genome sequencing, done using MinION and HiSeq platforms, to examine antibiotic resistance determinants among four multidrug resistant bacteria isolated from fish farm effluent in Jeju, South Korea. The combined data was used to ascertain the association between ARGs and MGEs. Hybrid assembly using HiSeq and MinION reads revealed the presence of IncFIB(K) and pVPH2 plasmids, whose sizes were verified using pulsed field gel electrophoresis. Twenty four ARGs and 95 MGEs were identified among the 955 coding sequences annotated on these plasmids. More importantly, 22 of 24 ARGs conferring resistance to various antibiotics were found to be located near MGEs, whereas about a half of the ARGs (11 out of 21) were so in chromosomes. Our results also suggest that the total phenotypic resistance exhibited by the isolates was mainly contributed by these putatively mobilizable ARGs. The study gives genomic insights into the origins of putatively mobilizable ARGs in bacteria subjected to selection pressure.

Metagenomic exploration of antibiotic resistome in treated wastewater effluents and their receiving water.

Environmental dissemination of antimicrobial resistance is a global health problem. Antimicrobial-resistant bacteria and antibiotic-resistant genes (ARGs) are constantly released into the environment through effluents (EFs) from wastewater treatment plants (WWTPs). Thus, requiring a better understanding of the selection and fate of ARGs in wastewater treatment processes. Therefore, we investigated the impacts of urban WWTP EFs on receiving water in the context of their resistomes and mobilomes. We used a HiSeq-based short read metagenomic approach to address the dynamics and diversity of ARGs in WWTP EF as well as the upstream (UP) and downstream (DN) river waters, followed by an investigation of plasmid-mediated ARGs. The abundance of ARGs at each site varied from 7.2 × 10-2 to 7.4 × 10-1 ARG copies per 16S rRNA gene copy, and EF samples showed the highest abundance, followed by DN and UP water samples. ARG diversity ranged from 121 to 686 types per site, and EF had the most diverse ARGs. Commonly identified ARGs in the EF and DN samples were clinically important and were absent in UP samples. The abundance of ARGs, mobile genetic elements (MGEs), and plasmid contigs found only in EF and DN were positively correlated with each other, indicating the importance of mobilomes in the dissemination of ARGs in the environment. Moreover, the proportions of plasmid-mediated ARGs was highest in the EF samples, followed by the DN and UP samples. These findings suggest that WWTP EF may act as a driving factor shaping the resistomes and mobilomes of receiving waters. In particular, a higher abundance of plasmid-mediated ARGs in WWTP EF suggests higher transmissibility in the DN environment.

Differentiation between grade 3 and grade 4 articular cartilage defects of the knee: fat-suppressed proton density-weighted versus fat-suppressed three-dimensional gradient-echo MRI.

BACKGROUND: Fat-suppressed (FS) proton density (PD)-weighted magnetic resonance imaging (MRI) and FS three-dimensional (3D) gradient-echo imaging such as spoiled gradient-recalled (SPGR) sequence have been established as accurate methods for detecting articular cartilage defects. PURPOSE: To retrospectively compare the diagnostic efficacy between FS PD-weighted and FS 3D gradient-echo MRI for differentiating between grade 3 and grade 4 cartilage defects of the knee with arthroscopy as the standard of reference. MATERIAL AND METHODS: Twenty-one patients who had grade 3 or 4 cartilage defects in medial femoral condyle at arthroscopy and knee MRI were included in this study: grade 3, >50% cartilage defects; grade 4, full thickness cartilage defects exposed to the bone. Sagittal FS PD-weighted MR images and FS 3D gradient-echo images with 1.5 T MR images were independently graded for the cartilage abnormalities of medial femoral condyle by two musculoskeletal radiologists. Statistical analysis was performed by Fisher's exact test. Inter-observer agreement in grading of cartilage was assessed using kappa coefficients. RESULTS: Arthroscopy revealed grade 3 defects in 17 patients and grade 4 defects in 4 patients in medial femoral condyles. For FS 3D gradient-echo images grade 3 defects were graded as grade 3 (n=15) and grade 4 (n=2), and all grade 4 defects (n=4) were correctly graded. However, for FS PD-weighted MR images all grade 3 defects were misinterpreted as grade 1 (n=1) and grade 4 (n=16), whereas all grade 4 defects (n=4) were correctly graded. FS 3D gradient-echo MRI could differentiate grade 3 from grade 4 defects (P=0.003), whereas FS PD-weighted imaging could not (P=1.0). Inter-observer agreement was substantial (kappa=0.70) for grading of cartilage using FS PD-weighted imaging, whereas it was moderate (kappa=0.46) using FS 3D gradient-echo imaging. CONCLUSION: FS 3D gradient-echo MRI is more helpful for differentiating between grade 3 and grade 4 cartilage defects than is FS PD-weighted imaging.

Effect of total knee arthroplasty on metabolic syndrome.

The purpose of this study was to evaluate the effect of changing activity after total knee arthroplasty (TKA) on metabolic syndrome with a follow-up period of 2 years. Two hundred consecutive patients who were to undergo TKA were prospectively enrolled. The patients' blood pressure, fasting plasma glucose level, the lipid profile, the waist circumference, the Knee Society score, and the Lower Extremity Activity Scale were measured preoperatively and at the 2-year follow-up visit. The data from 169 patients were finally collected and reviewed. Two years after primary TKA, there was no change in the prevalence of metabolic syndrome, despite that the patients had a significant increase of their physical activity.

Codium fragile Ameliorates High-Fat Diet-Induced Metabolism by Modulating the Gut Microbiota in Mice.

Codium fragile (CF) is a functional seaweed food that has been used for its health effects, including immunostimulatory, anti-inflammatory, anti-obesity and anti-cancer activities, but the effect of CF extracts on obesity via regulation of intestinal microflora is still unknown. This study investigated anti-obesity effects of CF extracts on gut microbiota of diet-induced obese mice. C57BL/6 mice fed a high-fat (HF) diet were given CF extracts intragastrically for 12 weeks. CF extracts significantly decreased animal body weight and the size of adipocytes, while reducing serum levels of cholesterol and glucose. In addition, CF extracts significantly shifted the gut microbiota of mice by increasing the abundance of Bacteroidetes and decreasing the abundance of Verrucomicrobia species, in which the portion of beneficial bacteria (i.e., Ruminococcaceae, Lachnospiraceae and Acetatifactor) were increased. This resulted in shifting predicted intestinal metabolic pathways involved in regulating adipocytes (i.e., mevalonate metabolism), energy harvest (i.e., pyruvate fermentation and glycolysis), appetite (i.e., chorismate biosynthesis) and metabolic disorders (i.e., isoprene biosynthesis, urea metabolism, and peptidoglycan biosynthesis). In conclusion, our study showed that CF extracts ameliorate intestinal metabolism in HF-induced obese mice by modulating the gut microbiota.

Anti-Inflammatory Properties and Gut Microbiota Modulation of Porphyra tenera Extracts in Dextran Sodium Sulfate-Induced Colitis in Mice.

Porphyra tenera (PT) is a functional seaweed food that has been reported for health benefits such as antioxidant, immunostimulant, anti-inflammation, and hepatoprotective effects. In this study, we investigated the effect of PT extracts on gut microbiota modulation in colitis-induced mice. The mice experiment was designed as three groups including normal mice (CTL), dextran sodium sulfate (DSS)-fed mice, and DSS plus PT extracts-fed mice (PTE). DSS was administrated through drinking water containing DSS for 1 week, and the PT extract was ingested into the gastrointestinal tract in mice. PT extract ameliorated the decreased body weight and colon length and improved disease activity index and pro-inflammatory cytokine expression. In addition, PT extract significantly shifted the gut microbiota of mice. DSS treatment significantly increased the portion of harmful bacteria (i.e., Helicobacter, Mucipirillum, and Parasutterella) and decreased the butyrate producing bacteria (i.e., Acetatifactor, Alistipes, Oscillibacter, and Clostridium_XIVb). PT extract increased the abundance of genera Clostridium_XIVb and also enriched some of predicted metabolic activities such as glyoxylate cycle, ethylmalonyl-CoA pathway, nitrate reduction, creatinine degradation, and glycine betaine metabolism. These results suggest that PT extract may ameliorate the DSS-induced colitis inflammation through regulating the compositions and functions of gut microbiota in mice.

Agreements between different methods of gap balance estimation in cruciate-retaining total knee arthroplasty.

The authors investigated the agreements between three different methods of estimating gap balance in cruciate-retaining (CR) total knee arthroplasty (TKA) with the use of a subvastus approach. One hundred consecutive CR TKAs were prospectively included in this study. After completing soft tissue release and bone cutting for CR TKA, flexion-extension gap balance was assessed using a distractor, spacer blocks, and trial components. Levels of agreement between the estimation techniques used were substantial. All three techniques were reliable in the assessment of gap balance. But, observations made during this study suggest that if more than one estimation technique is applied during CR TKA, the incidence of undetected gap imbalance can be reduced.

Factors affecting flexion gap tightness in cruciate-retaining total knee arthroplasty.

With the exception of flexion gap tightness, which is common in cruciate-retaining (CR) total knee arthroplasty (TKA), the risk factors of flexion gap tightness have not been described. This retrospective study characterized factors that are associated with flexion gap tightness in CR TKA. Data on 203 consecutive knees that underwent CR TKA were reviewed. The prevalence rate of flexion gap tightness was 21.1%. By logistic regression analysis after adjusting for age, preoperative flexion contracture, and referencing method used for femoral sizing, insufficient tibial slope remained a significant independent risk factor of flexion gap tightness. Although excessive tibial slope should be avoided, the findings of the present study demonstrate that the risk of flexion gap tightness can be reduced by increasing the tibial slope in CR TKA.

Radial tear of the medial meniscal root: reliability and accuracy of MRI for diagnosis.

OBJECTIVE: The purpose of this study was to determine the reliability and accuracy of MRI in the diagnosis of radial tears of the medial meniscal root. MATERIALS AND METHODS: The MR images of 192 patients who underwent arthroscopy and MRI of the knee from July 2003 through March 2006 were retrospectively reviewed. MR images were independently scored by two observers for the presence of radial tear of the medial meniscal root. Interobserver agreement in detection of these tears was assessed with kappa values. The differences in areas under the receiver operating characteristic curves were assessed with a univariate z-score test. RESULTS: Arthroscopy revealed that 29 patients had radial tears of the medial meniscal root. The sensitivity, specificity, and accuracy of MRI for one reader were 90% (26/29), 94% (154/163), and 94% (180/192) and for the other reader were 86% (25/29), 95% (155/163), and 94% (180/192). Interobserver agreement for radial tears of the medial meniscal root was very high (kappa = 0.93). The areas under the receiver operating characteristic curves for each reader were 0.97 and 0.96, which were not significantly different. There was no significant difference in detection of medial meniscal root tears on T2-weighted coronal images compared with the overall interpretation for both readers. Other image sequences had significantly different sensitivity or specificity for one or both readers (McNemar statistic). CONCLUSION: MRI of the knee is reliable and accurate for detection of radial tears of the medial meniscal root. Coronal T2-weighted imaging is the most useful MRI sequence.

Expression of vascular endothelial growth factor and angiogenesis in the diabetic frozen shoulder.

The purpose of this study was to investigate neovascularization and the expression of vascular endothelial growth factor (VEGF) in patients with diabetic frozen shoulders. Eleven patients with diabetic frozen shoulders underwent arthroscopic lysis of adhesions, and we observed the reported findings. VEGF expression was determined by immunohistochemistry and Western blot analysis, and the density of vessels was evaluated based on CD34 immunoreactivity by use of samples of the synovial tissue. For the control group, we took 5 samples of synovium from patients undergoing shoulder arthroscopy. The arthroscopic findings showed hyperemia of the synovial tissue in all cases of diabetic frozen shoulder. This synovium showed stronger immunostaining to VEGF (P = .010) and CD34 (P = .011) than the control synovial tissue. Western blot analysis also showed a stronger VEGF intensity than in the control group. We postulate that VEGF is synthesized and secreted in the synovium of diabetic frozen shoulders and VEGF may have some role in the pathogenesis and neovascularization of frozen shoulders in diabetic patients.