Association of IL-6 -174G > C and -572G > C Polymorphisms with Risk of Legg-Calve-Perthes Disease in Iranian Children.

BACKGROUND: Legg-Calve-Perthes disease (LCPD) is an idiopathic avascular necrosis of the capital femoral epiphysis of the femoral head with multifactorial etiology. The aim of this study was to analyze the association of IL-6 polymorphisms with LCPD risk in Iranian children. Methods: The study comprised of 45 children diagnosed with LCPD and 60 healthy subjects. The IL-6 -174 G > C and -597 G > C polymorphisms were genotyped by PCR-RFLP assay. Odds ratios (OR) and 95% confidence intervals (CI) were calculated on the risk genotypes and alleles. Results: The mutant homozygote genotype (CC) of IL-6 -174 G > C polymorphism was associated with increased risk of LCPD (OR 3.554; 95% CI: 0.1.578-8.004; p = 0.002). There was no significant association between IL-6 -597 G > C polymorphism and an increased risk of LCPD. Conclusions: Our results suggest that the IL-6 -174 G > C but not the IL-6 -597 G > C polymorphism may increase LCPD susceptibility in Iranian children.

Effects of whole body vibration with exercise therapy versus exercise therapy alone on flexibility, vertical jump height, agility and pain in athletes with patellofemoral pain: a randomized clinical trial.

BACKGROUND: Patellofemoral pain (PFP) is the most prevalent orthopedic problem in active young adults. Due to its multifactorial etiology, a variety of therapeutic measures have been adopted to treat PFP, including exercise therapy, electrotherapy, and manual therapy. It has also been suggested that whole body vibration (WBV) can improve neuromuscular function in persons with knee problems. The aim of the present study was to evaluate the effects of adding WBV to routine exercise programs on flexibility, vertical jump height, agility and pain in athletes with PFP. METHODS: Twenty-four male athletes with PFP were randomized into two groups of WBV + exercise (n = 12) or exercise only (n = 12). Participants received their interventions during 4 consecutive weeks (12 sessions). Pain intensity, flexibility and agility were assessed respectively as score on a numerical rating scale, the sit-and-reach test, and a modified T-test, and vertical jump height was measured to the nearest centimeter. The tests were done before and after the interventions, and the results were compared between the two groups. Independent t-tests and paired t-tests were used for between- and within-group comparisons, respectively. RESULTS: After the interventions, all variables for vertical jump height, flexibility, agility and pain intensity improved significantly in both groups (p < 0.05). The flexibility test showed significantly greater improvement in the WBV + exercise group (p<0.001), whereas for vertical jump height, agility and pain intensity, there were no statistically significant differences between groups (p>0.05). CONCLUSIONS: The present findings showed that exercise therapy with and without WBV can significantly decrease pain and increase agility, vertical jump height and flexibility in athletes with PFP. Adding WBV to routine exercise therapy, however, can augment the effects of the latter on flexibility. TRIAL REGISTRATION: IRCT, IRCT20090831002391N39. Registered 7 February 2018, https://en.irct.ir/search/result?query=IRCT20090831002391N39 .

Carpal Dimensions by Plain Wrist Radiography in Patients with Severe Carpal Tunnel Syndrome.

In this study, we evaluated the diagnostic value of carpal dimensions in wrist plain radiography for the screening of carpal tunnel syndrome (CTS). This is a case-control diagnostic probe in which patients with severe CTS documented by electrodiagnostic study and healthy subjects as controls were enrolled. In the posteroanterior view of the wrist plain radiography in both groups, we defined and measured the carpal ratio, and the results were analyzed deploying statistical software. In this study, 119 participants, including 50 patients and 69 healthy subjects, were recruited. According to the ROC chart, the cutoff points, positive and negative predictive values, and the diagnostic accuracy for the cutoff points were calculated.

The Frequency of Burnout among Iranian Orthopedic Surgeons and Residents.

Background: Burnout is an emotional, psychological, and physical exhaustion syndrome with feelings of negativism toward one's job and reduced attention to clients. This complication is caused by the lack of control over work-related stress. Physicians, especially surgeons, are at higher risk for burnout due to critical responsibility and heavy workload. Given the importance and consequences of this dilemma, the present study aimed to investigate the frequency of burnout among orthopedic surgeons and residents. Methods: The present cross-sectional, analytical study was conducted in 2019 in the cities of Tehran and Yazd, in Iran. A total of 180 orthopedic surgeons and residents participated in the study. A demographic characteristics form and the Maslach Burnout Inventory (MBI) were employed to assess burnout in the participants. Results: The mean age of the participants was 42.8 years, and 94.4%, 23.9%, 52.2%, and 23.9% of the participants were male, residents, general orthopedic specialists, and fellowship-trained orthopedics, respectively. Out of 180 participants, 90 (50%) cases were suffering from burnout, of whom 26.7%, 16.1%, and 7.2% got a pathological score in one, two, and three criteria. No significant relationship was observed between burnout and gender, marital status, years of experience, and the average number of surgeries per week. However, there was a significant association between burnout and younger age, lower academic rank or being a resident, working in the public sector, and spending less time in leisure and sports activities. Conclusion: The prevalence of burnout (50%) among orthopedists was remarkable and worrying. The frequency of burnout was higher among residents and the ones working in the public sector. This study demonstrates that the issue of burnout and its related risk factors have to be addressed in Iranian orthopedic surgeons and residents.

Slow release curcumin-containing soy protein nanoparticles as anticancer agents for osteosarcoma: synthesis and characterization.

Curcumin-containing soy protein nanoparticles (curcumin-SPNs) were synthesized by desolvation (coacervation) method and characterized by SEM, DLS, FTIR, and XRD. For anticancer evaluation, osteogenic sarcoma (SAOS2) cell lines were incubated with different concentrations of nanostructures. The dialysis method was used for assessment of drug release. Intracellular reactive oxygen species (ROS) were evaluated in IC50 dose after 24 h of exposure to free curcumin and curcumin-SPNs. Characterization data showed that the size of drug-free SPNs and curcumin-SPNs were 278.2 and 294.7 nm, respectively. The zeta potential of drug-free SPNs and curcumin-SPNs were - 37.1 and - 36.51 mv, respectively. There was no significant difference between the control and drug-free SPNs groups in terms of cell viability (p > 0.05). The viability of cells in different concentrations of the designed curcumin-SPNs in Saos2 cell line was significantly higher than free drug (p < 0.05). The release of curcumin showed that more than 50% of the drug was released in the first 2 h of incubation. After this time, the slow release of drug was continued to 62-83% of drug. IC50 values of free curcumin and curcumin-SPNs (1/10) were 156.8 and 65.9 µg/mL, respectively (a free curcumin IC50 was 2.4 times more than curcumin-SPNs). Slow-release of the curcumin causes the cell to be exposed to the anticancer drug for a longer period of time. The intracellular ROS levels significantly increased in an IC50 dose after 24 h of exposure to both free curcumin and curcumin-SPNs compared with controls (p < 0.05).

A meta-analysis for association of TNF-α -308G>A polymorphism with susceptibility to Ankylosing Spondylitis.

OBJECTIVE: We performed a meta-analysis of all eligible studies on the association of TNF-α -308G>A polymorphism with risk of Ankylosing spondylitis (AS). METHODS: A comprehensive literature research was performed in online databases. RESULTS: A total of 28 studies with 4489 cases and 5919 controls were included. Pooled ORs showed a significant association between TNF-α -308G>A polymorphism and risk of AS. Moreover, stratified analysis by ethnicity showed a significant association between TNF-α -308G>A polymorphism and AS risk in Asians, Caucasians and Mixed populations, but not in Chinese population. CONCLUSION: This meta-analysis suggested that the TNF-α -308G>A polymorphism was associated with AS risk.

The Prevalence of Human Immunodeficiency Virus Infection in Patients with Sexually Transmitted Diseases.

BACKGROUND: Human immunodeficiency virus (HIV) transmission pattern in Iran has been changed from injection drug to sexual contact. Lack of accurate assessment of HIV in people with sexually transmitted diseases (STDs) in Iran prompted us to conduct this study to determine the frequency of HIV infection in these patients. MATERIALS AND METHODS: In this cross-sectional study which conducted in 2016-2017, overall, 190 patients with STDs referring to two hospitals of Hamadan were enrolled in the study. All of the patients were examined for HIV in the first visit by rapid test and then 1 and 4 months later by the 4th generation ELISA. A questionnaire including demographic data, clinical manifestations, and high-risk behaviors was completed for all of the referring people. The collected data were analyzed using appropriate statistical tests. RESULTS: Of 190 patients, 126 (66.3%) were female with a mean age of 34.1 ± 10.1 years and 64 (33.7%) were male with a mean age of 30.8 ± 7.8 years. One hundred twenty-eight (67.4%) got married, 73 (38.4%) and 76 (40%) had a diploma and postgraduate education, respectively, 32 (16.8%) mentioned the history of unsafe sex, and 23 (12.1%) had used condoms continuously during sexual contacts. The most common STDs were reported genital warts, 107 patients (56.3%), vaginal discharge (28, 14.7%), and genital ulcer (33, 17.4%). Two (1%) patients were positive for HIV at the first visit. CONCLUSION: Patients with STDs should be considered as an important source of HIV transmission, so clinicians should pay more attention to screening these patients for HIV infection.

Association of catechol-O-methyltranferase 472G>A (Val158Met) polymorphism with susceptibility to fibromyalgia syndrome.

BACKGROUND: Several lines of research have suggested that the 472G > A (Val158Met) polymorphism at Catechol-O-methyltranferase (COMT) gene is implicated in the pathophysiology of FMS. Here, we have evaluated the association of COMT 472G > A polymorphism with risk of FMS. METHODS: In this study 250 patients with FMS and 250 healthy controls were evaluated for COMT 472G > A polymorphism by RFLP-PCR assay. RESULTS: There were no significant differences in the allele and genotype frequencies of COMT 472G > A polymorphism between FMS cases and healthy controls. CONCLUSIONS: Our results suggested that the COMT 472G > A polymorphism may not be risk factor for development of FMS.

Association of ESRα XbaI A > G, ESRα PvuII T > C and ESRß AlwNI T > C Polymorphisms with the Risk of Developing Adolescent Idiopathic Scoliosis: A Systematic Review and Genetic Meta-analysis.

Several association studies of genes polymorphisms on estrogen receptors-α and ß with respect to adolescent idiopathic scoliosis (AIS) have been published in the past two decades. However, the association with AIS, especially among different ethnic subgroups, still remains controversial. Thus, we investigated these inconclusive data by performing a meta-analysis to systematically evaluate the association. A literature search was conducted in the PubMed, ISI Web of Science, EMBASE, SCOPUS, EBSCO, Cochrane Library, China National Knowledge Infrastructure (CNKI) and Wanfang databases until January 20, 2018. The strength of relationship was assessed using odds ratios (ORs) and 95% confidence intervals (95%CIs). A total of 12 case-control studies with 4,304 cases of AIS and 3,123 controls met our criteria. The pooled ORs indicated that the ESRα XbaI A > G, ESRα PvuII T > C and ESRß AlwNI T > C polymorphisms were not significantly associated with the risk of developing AIS in the overall analysis. However, we found a significant association between the ESRα XbaI A > G polymorphism and AIS under the homozygote model (GG versus AA; OR = 1.448, 95%CI: 1.052-1.993; p = 0.023). The present meta-analysis suggests that the ESRα XbaI A > G, ESRα PvuII T > C and ESRß AlwNI T > C polymorphisms may not be associated with the risk of developing AIS in the overall analysis. However, ESRα XbaI A > G might have an influence on the susceptibility to develop AIS among Asians. Considering the limited sample size and ethnicity, further larger studies are needed to provide a more precise estimation of the associations.

Association of the IL-6 -174G > C (rs1800795) Polymorphism with Adolescent Idiopathic Scoliosis: Evidence from a Case-Control Study and Meta-Analysis.

Recent epidemiological studies have identified that the -174G > C (rs1800795) polymorphism in the promoter region of the interleukin-6 ( IL-6 ) gene is associated with the risk of developing adolescent idiopathic scoliosis (AIS), but they presented inconsistent and controversial results. Thus, we performed a case-control study and meta-analysis to derive a more precise estimation of the relationship between the IL-6 -174G > C polymorphism and the risk of developing AIS. A total of 80 patients with AIS and 80 matched healthy control subjects were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. In addition, all eligible studies published up to June 2018 were identified through a search in the PubMed, EMBASE, Google Scholar, and China National Knowledge Infrastructure (CNKI) databases. We calculated the odds ratios (ORs) and 95% confidence intervals (95%CIs) to assess the association. A total of 10 eligible studies comprising 1,695 AIS cases and 2,097 healthy controls were included in the meta-analysis. The pooled data suggested a significant association between the IL-6 -174G > C polymorphism and the susceptibility to develop AIS, which was demonstrated under 4 genetic models, that is, the allelic (C versus G; OR = 0.671; 95%CI: 0.457-0.985; p = 0.042), heterozygous (CG versus GG; OR = 0.734; 95%CI: 0.554-0.973; p = 0.032), dominant (CC + CG versus GG; OR = 0.660; 95%CI: 0.440-0.990; p = 0.044) and recessive models (CC versus CG + GG; OR = 0.506; 95%CI: 0.264-0.970; p = 0.040). The stratification analysis by ethnicity revealed an increased risk of developing AIS in Caucasians, but not in Asians. The present meta-analysis, which is inconsistent with the previous meta-analysis, suggests that the IL-6 -174G > C polymorphism may increase the individual susceptibility to develop AIS, especially in Caucasians, and it could serve as a biomarker to predict the population at high risk of developing AIS.

Evaluating the Toxicity and Histological Effects of Al2O3 Nanoparticles on Bone Tissue in Animal Model: A Case-Control Study.

The applications of nanostructures have been limited by their different toxicities. So, the investigation of these toxicities is necessary before nanostructure application. This study aimed to evaluate the effect of aluminum oxide (Al2O3) nanoparticles on bone density in Wistar rat. Al2O3 nanoparticle was prepared by the sol-gel method. Characterization was done by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Sixty-four male adult Wistar rats were divided into eight groups including six groups intravenously treated with Al2O3 nanoparticle at concentrations of 25, 50, 100, 250, 500, and 1000 µg/ml: one group received food and water as the control group, and one group received food and water as well as intravenously distilled water as an injection control group. After 41 days, bone density was analyzed by dual-energy X-ray absorptiometry (DEXA). According to X-ray diffraction, the average particle size for Al2O3 nanoparticles was 20.85 nm. The data of densitometry showed that the bone density of right and left foot was reduced in concentrations of 250, 500, and 1000 µg/ml that were statistically significant in comparison with the control group. The reduction of bone density was increased with the enhancement of nanostructures concentration. The effect of Al2O3 nanoparticles on bone density was similar in the left and right legs. Histopatholological assessment also showed that Al2O3 nanoparticles (250, 500, and 1000 µg/ml) lead to significant reduction of trabeculae. Empty lacunae are observed in these three groups. Considering that high concentrations of Al2O3 nanoparticles had toxicity on bone tissue, it must be used by more caution, especially its use as a coating in different devices such as implants, surgical instruments, and bone prostheses.

Association of eNOS 27-bp VNTR, 894G>T and 786T>C polymorphisms with susceptibility to Legg-Calve-Perthes Disease in Iranian children.

BACKGROUND: The aim of this study was to analyze the association of eNOS polymorphisms with risk of Legg-Calve-Perthes Disease (LCPD). METHODS: The study comprised of 45 LCPD patients and 55 controls. The eNOS polymorphisms were genotyped with PCR and by PCR-RFLP. RESULTS: The eNOS 894G > T and -786T > C polymorphisms were significantly associated with an increased risk of LCPD. However, there was no significant association between eNOS 27-bp VNTR polymorphism and LCPD risk. CONCLUSION: Our results suggest that the eNOS 894G > T and -786T > C polymorphisms may be a risk factor for LCPD in Iranian children, but not 27-bp VNTR polymorphism.

Association of rs2234693 and rs9340799 polymorphisms of estrogen Receptor-1 gene with radiographic defined knee osteoarthritis: A meta-analysis.

OBJECTIVE: To evaluate the association of ESR1 rs2234693 and rs9340799 polymorphisms with radiographic defined knee osteoarthritis (OA), a case-control and meta-analysis was performed. METHODS: A total of 25 case-control studies with 7,144 cases and 8,468 controls with were included. RESULTS: There was a significant association between rs2234693 polymorphism and radiographic knee OA under heterozygote model (CT vs. TT: OR = 1.164, 95% CI 1.053-1.286, p = 0.003). However, there was no association between rs9340799 and radiographic knee OA. In subgroup analysis by ethnicity, risk estimates were not augmented. CONCLUSIONS: Our results showed that the ESR1 rs2234693 polymorphism might be associated with radiographic defined knee OA, but not rs9340799.

Association of GSTM1, GSTT1, GSTM3, and GSTP1 Genes Polymorphisms with Susceptibility to Osteosarcoma: a Case- Control Study and Meta-Analysis

Background: Some studies have investigated the association of GSTM1, GSTT1, GSTM3, and GSTP1 polymorphisms with susceptibility to osteosarcoma; however, these studies results are inconsistent and inconclusive. In order to drive a more precise estimation, the present case-control study and meta-analysis was performed to investigate association of GSTM1, GSTT1, GSTM3, and GSTP1 polymorphisms with osteosarcoma. Methods: Eligible articles were identified by a search of several electronic databases for the period up to May 5, 2018. Odds ratios were pooled using either fixed-effects or random effects models. Results: Finally, a total of 24 case-control studies with 2,405 osteosarcoma cases and 3,293 controls were included in the present meta-analysis. Overall, significantly increased osteosarcoma risk was found when all studies were pooled into the meta-analysis of GSTT1 (Null vs. Present: OR= 1.247 95% CI 1.020-1.524, P= 0.031) and GSTP1 polymorphism (B vs. A: OR= 8.899 95% CI 2.722-29.094, P≤0.001). In the stratified, significantly increased osteosarcoma risk was observed for GSTT1 polymorphism among Asians (Null vs. Present: OR= 1.300 95% CI 1.034-1.635, P= 0.025), but not among Caucasians. Conclusions: This meta-analysis demonstrated that GSTP1 and GSTT1 null genotype are associated with the risk of osteosarcoma. Future large welldesigned epidemiological studies are warranted to validate our results.

Association of TNF-α-308 G > A and -238G > A polymorphisms with knee osteoarthritis risk: A case-control study and meta-analysis.

OBJECTIVE: A comprehensive search on electronic databases was conducted to identify all eligible studies of TNF-α polymorphisms and knee osteoarthritis (OA). METHODS: Eight studies on TNF-α -308 G > A and three on TNF-α -238G > A polymorphism were identified. RESULTS: Overall, the pooled ORs indicated that neither TNF-α -238G > A nor -238G > A polymorphism was associated with knee OA risk. Similarly, in the stratified analysis by ethnicity, no significant association was found. CONCLUSION: This meta-analysis results inconsistent with the previous meta-analyses showed that the TNF-α -308 G > A and -238G > A polymorphisms may not be associated with the susceptibility to knee OA.

Association of MTHFR and TNF-α genes polymorphisms with susceptibility to Legg-Calve-Perthes disease in Iranian children: A case-control study.

OBJECTIVE: The aim of this study was to assess the association of MTHFR and TNF-α genes polymorphisms with Legg-Calvé-Perthes' disease (LCPD) risk in the Iranian children. METHODS: A total of 45 children with LCPD and 55 healthy controls were recruited to the study. Genotyping was performed via the RFLP-PCR method and genetic risk was calculated by odds ratio (OR) with its corresponding 95% confidence interval (CI). RESULTS & CONCLUSION: Our case-control study failed to determine any association of MTHFR (677C > T and 1298A > C) and TNF-α (-308G > A and -238G > A) polymorphisms with LCPD risk. More studies with larger sample size are warranted to validate our findings.

Association of GDF-5 rs143383 polymorphism with radiographic defined knee osteoarthritis: A systematic review and meta-analysis.

OBJECTIVE: To assess the association of GDF-5 rs143383 polymorphism with radiographic defined knee osteoarthritis (OA), a systematic review and meta-analysis was conducted. METHODS: A total of 17 relevant case-control studies with 7424 cases and 11,310 controls was collected from several electronic databases up to June 2018. RESULTS: The pooled results showed that GDF-5 rs143383 polymorphism was significantly associated with radiographic defined knee OA in overall and stratified analysis by ethnicity, source of controls and genotyping techniques. CONCLUSIONS: The GDF-5 rs143383 polymorphism might be used as a relevant risk estimate for radiographic defined Knee OA.

Genetic Association between ERCC2, NBN, RAD51 Gene Variants and Osteosarcoma Risk: a Systematic Review and Meta-Analysis

Background: To date, only a few studies have investigated associations between ERCC2, NBN, and RAD51 variants and risk of developing osteosarcoma. In this systematic review and meta-analysis, we focused on clarifying links. Materials and Methods: We systematically searched PubMed, Google Scholar, and ISI web of knowledge databases to identify relevant studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to calculate the strength of associations with fixed effect models. Results: No statistical evidence of association was found between ERCC2 rs13181 (G vs. T: OR= 1.224, 95% CI: 0.970-1.545, p= 0.088; GT vs. TT: OR= 1.135, 95% CI: 0.830-1.552, p= 0.428; GG vs. TT: OR= 1.247, 95% CI: 0.738-2.108, p= 0.409; GG+GT vs. TT: OR= 1.174, 95% CI: 0.929-1.484, p= 0.179; GG vs. GT+TT: OR= 1.476, 95% CI: 0.886-2.460, p= 0.135), ERCC2 rs1799793 (GA+AA vs. GG: OR= 1.279, 95% CI: 0.912-1.793, p= 0.154), NBN rs709816 (OR= 1.047, 95% CI: 0.763-1.437, p= 0.775), NBN rs1805794 (OR= 1.126, 95% CI: 0.789-1.608, p= 0.513), RAD51 rs1801320 (OR= 0.977, 95% CI: 0.675-1.416, p= 0.904), RAD51 rs1801321 (TT+GT vs. GG: OR= 1.167, 95% CI: 0.848-1.604, p= 0.343), RAD51 rs12593359 (GG+GT vs. TT: OR= 0.761, 95% CI: 0.759-1.470, p= 0.744) polymorphisms and osteosarcomas. The lack of the original data limited our further evaluation of the adjusted ORs concerning age and gender; however, the previous individual studies results indicated the age- and gender-specific effects of two ERCC2 rs1799793 and NBN rs1805794 variants on osteosarcoma risk. Conclusion: The results suggested a lack of association between the ERCC2 (rs13181 and rs1799793), NBN (rs709816 and rs1805794), and RAD51 (rs1801320, rs1801321, and rs12593359) variants with osteosarcoma risk. Further comprehensive and well-designed studies are required to assess the role for ERCC2, NBN, RAD51 variants in osteosarcoma development more adequately.

Association between the DNA Repair Gene XRCC3 rs861539 Polymorphism and Risk of Osteosarcoma: a Systematic Review and Meta-Analysis

Objective: Although there are a few studies investigating the relation between X-Ray Repair Cross Complementing 3 (XRCC3) gene rs861539 polymorphism and osteosarcoma (OSA), the results are inconsistent. Therefore, we performed this systematic review and meta-analysis to clarify the associations between XRCC3 rs861539 polymorphism and OSA risk. Methods: We have retrieved published literature from PubMed, Google scholar, and ISI Web of Knowledge up to 25 January 2017. Odds ratios were pooled using either fixed-effects or random effects models. Overall and subgroup analyses were performed. Statistical analysis was performed running comprehensive meta-analysis (CMA) 2.0 software. Results: A total of four studies with 515 cases and 1,109 controls were identified in order to investigate the association between XRCC3 rs861539 polymorphism and OSA risk. The results showed that XRCC3 rs861539 polymorphism was associated with OSA in allelic (T vs. C: OR= 1.563, 95% CI: 1.244-1.963, p= <0.001), homozygote (TT vs. CC: OR= 2.574, 95% CI: 1.573-4.212, p= <0.001), dominant (TT+TC vs. CC: OR= 1.255, 95% CI: 1.011-1.558, p= 0.039), and recessive (TT vs. TC+CC: OR= 2.224, 95% CI: 1.393-3.552, p= 0.001), but not with heterozygote (TC vs. CC: OR= 1.361, 95% CI: 0.982-1.885, p= 0.064). The XRCC3 rs861539 polymorphism conferred susceptibility to OSA in Asians, but not in Caucasians. Additionally, we observed no evidence of publication bias. Conclusion: To the best of our knowledge, this is the first meta-analysis investigating the association between XRCC3 rs861539 polymorphism and OSA risk. Our results revealed a significant association between the XRCC3 rs861539 polymorphism and risk of OSA, especially in Asian populations. Future more comprehensive and well-designed case control studies with larger sample size are needed to warrant these findings.

The Normal Value of Tibial Tubercle Trochlear Groove Distance in Patients With Normal Knee Examinations Using MRI.

Patellar instability is a multifactorial common knee pathology that has a high recurrence rate, and the symptoms continue and ultimately predispose the patient to chondromalacia and osteoarthritis. Tibial tuberosity-trochlear groove distance (TTTG) is very important in the assessment of patellofemoral joint instability. The purpose of this study was to report the normal value of TTTG in males and females in different age groups and to assess the reliability of MRI in measuring TTTG. All patients presenting with knee pain and normal examinations of the knee joint, with a normal MRI report, referring to Shahid Sadoughi hospital of Yazd, Iran, from April 2014 to September 2014, were included in the study. MR images were studied once by two radiologists and for the second time by one radiologist. Mean value of TTTG was reported for males and females and in three age groups. Intra- and inter-observer reliability was calculated. A total of 98 patients were eligible to evaluate during 6 months (68 male and 30 female). Mean TTTG was 10.9±2.5 mm in total, which was 10.8±2.8 mm and 11.3±2.3 mm in males and females, respectively (P>0.05). Mean TTTG in males ≤30 years, 30-50 years and, ≥51-year-old were 10.8±2.6 mm, 10.8±2.7 mm, and 10.8±2.6 mm, respectively; that was 12.1±3.4 mm, 11.4±1.9 mm, and 10.5±1.7 mm in females ≤30 years, 31-50 years and, ≥51-year-old, respectively (95% CI). The coefficient of variation was <10% for both intra- and interobserver analysis. The results of the present study showed no significant difference in TTTG value between males and females in different age groups. In addition, it demonstrated that MRI is a reliable method in assessment of TTTG and identified normal value for TTTG at 10.9±2.5 mm.