Opioid use disorder has increased in the world in recent years and Iran ranks first in terms of opium smoking in the world. In fact, opium smoking by traditional methods, in addition to dependence on morphine, is a behavioral addiction in Iran. The body position during opium smoking is usually non-standard and non-ergonomic. Over time, changes in muscle tissue, tendons and ligaments, and the connective tissue go from elasticity to neuromuscular plasticity. This study aims to compare sway back posture and musculoskeletal problems between opium smokers and non-drug users. In this comparative and cross-sectional study, 80 opium smokers were compared with 74 non-drug users in terms of sway angle (sway back posture), and musculoskeletal complaints (NORDIC questionnaire) and the association of possible risk factors was investigated. Data were analyzed by Kolmogorov-Smirnov, Correlation Coefficient and paired-t tests using SPSS version 23. There were significant differences between two groups in terms of sway back posture (P=0.007), and neck (<0.001), upper back (<0.001) and lower back (0.006) musculoskeletal complaints. Homelessness, the lifetime duration of opium smoking (in months), and the duration of daily opium smoking (in minutes) had significant correlation with sway back posture and musculoskeletal complaints. Homelessness was the strongest predictor and had strongest correlation. Overall, an increase in the duration of sitting in non-ergonomic positions could lead to increase in sway angle and sway back posture and increase in musculoskeletal complaints of neck, upper back and lower back due to the non-neutral posture of opium smoking. It seems that plasticity and structural and functional adaptations of the posture occurs due to opium smoking and further studies are recommended.

Opium smoking for long hours and over many years is common in Iran, and the Covid-19 pan-demic and false beliefs about the protective effects of that opium against COVID-19 infection has caused the increasing of opium smoking during the pandemic. The aim of this study was to in-vestigate the relationship between non-ergonomic positions of traditional opium smoking in Iran with the occurrence of neck pain and disability, forward head posture and hyperkyphosis. In this cross-sectional and correlation study 120 people who smoke opium were selected based on the inclusion criteria and were interviewed about their addiction profile and evaluated for the pres-ence of pain and disability in the neck by Maudsley Addiction Profile, Leeds Dependence Ques-tionnaire, the Visual Analog Scale and Neck Disability Index. Also, they were evaluated about forward head posture (FHP) through side view photography and hyperkyphosis (HK) through flexible ruler. Data were analyzed by correlation coefficient tests and stepwise linear regression. There was a significant relation between homelessness, the duration of lifetime opium smoking (months), the duration of daily opium smoking (minutes) and drug dependence severity with the severity of neck pain, neck disability, forward head posture and hyperkyphosis. Homelessness is the strongest predictive variable of the possibility of neck pain and disability, FHP and HK, fol-lowed by ‘‘the number of months of opium smoking’’ and ‘‘the number of minutes of opium smoking in one day’’ respectively. Increasing the duration of sitting in non-ergonomic positions can lead to neck pain and disability, FHP and HK due to their non-neutral posture in opium smokers.

Today, due to recent developments in technology, children devote plenty of time for screen viewing. However, its harmful effects are not yet clear. The purpose of present study was to examine the associations among screen viewing and sleep duration, and body mass index (BMI) in under-five years old children. This cross-sectional study was conducted with 322 under-five healthy children that were selected using multistage stratified cluster sampling method in 2017. The data that were gathered by time-use diary method were analyzed using Kolmogorov-Smirnov test, Spearman correlation tests, multiple linear regression analysis, one-way ANCOVA, two-way ANCOVA. There was a negative correlation between screen time and sleep duration (rs = -0.42, p = 0.00), positive correlation between screen time and BMI (rs = 0.38, p = 0.00) and sleep duration negatively correlated with BMI (rs = -0.22, p = 0.00). screen viewing was a predictive factor for both sleep duration (β = -0.26, p = 0.00) and BMI (β = -0.26, p = 0.00). screen viewing had a significant impact on sleep duration (4, 314) = 5.02, P = 0.001) and BMI (F (4, 314) = 1.16, P=0.298). Results of this study indicated that screen viewing is related to sleep duration and BMI in under-five children. furthermore, screen time has an impact on sleep duration and BMI scores of children. findings of our study suggest that sleep duration negatively is associated with BMI in under-five-year-old children.