Nahid Rahmani

Reliability of surface electromyography in the assessment of paraspinal muscle fatigue: an updated systematic review.

OBJECTIVE The purpose of this study was to review the literature to determine whether surface electromyography (EMG) is a reliable tool to assess paraspinal muscle fatigue in healthy subjects and in patients with low back pain (LBP). METHODS A literature search for the period of 2000 to 2012 was performed, using PubMed, ProQuest, Science Direct, EMBASE, OVID, CINAHL, and MEDLINE databases. Electromyography, reliability, median frequency, paraspinal muscle, endurance, low back pain, and muscle fatigue were used as keywords. RESULTS The literature search yielded 178 studies using the above keywords. Twelve articles were selected according to the inclusion criteria of the study. In 7 of the 12 studies, the surface EMG was only applied in healthy subjects, and in 5 studies, the reliability of surface EMG was investigated in patients with LBP or a comparison with a control group. In all of these studies, median frequency was shown to be a reliable EMG parameter to assess paraspinal muscles fatigue. There was a wide variation among studies in terms of methodology, surface EMG parameters, electrode location, procedure, and homogeneity of the study population. CONCLUSIONS The results suggest that there seems to be a convincing body of evidence to support the merit of surface EMG in the assessment of paraspinal muscle fatigue in healthy subject and in patients with LBP.

Application of perineometer in the assessment of pelvic floor muscle strength and endurance: A reliability study

Despite different studies on the reliability of pelvic floor muscle assessment, there is still no general consensus on the most valid and reliable method. The purpose of this study was to investigate the intra-rater (within-day and between-days) reliability of perineometer in the assessment of pelvic floor muscle strength and endurance. Following ethical approval, 15 healthy women aged from 22 to 50-years old, with no history of low back pain were recruited. The Peritron perineometer instrument was used to measure pelvic floor muscle strength and endurance. Two measurements were taken on the same day with an hour interval to assess within-day reliability and the third measurement was taken five days later to determine between-days reliability. Intraclass Correlation Coefficients (ICCs) and the level of agreement between measurements were used for data analysis. The high ICC values (0.95 for strength and 0.94 for endurance) and high level of agreement between measurements indicated high within-day reliability for pelvic floor muscle strength and endurance. The perineometer was also shown to be reliable for between-days measurements with high ICC (0.88 for strength and 0.83 for endurance) and high level of agreement between measurements. The results demonstrated that the perineometer appears to be a highly reliable method of measuring pelvic floor muscle strength and endurance when measurements are taken in healthy subject by the same investigator.

The effect of pelvic floor muscle exercise on women with chronic non-specific low back pain.

Dysfunction of spinal stability seems to be one of the causes of low back pain (LBP). It is thought that a large number of muscles have a role in spinal stability including the pelvic floor muscle (PFM). The purpose of this study was to investigate the effect of PFM exercise in the treatment of chronic LBP. After ethical approval, a randomized controlled clinical trial was carried out on 20 women with chronic LBP. Patients were randomly allocated into two groups: an experimental and a control group. The control group was given routine treatment including electrotherapy and general exercises; and the experimental group received routine treatment and additional PFM exercise. Pain intensity, functional disability and PFM strength and endurance were measured before, immediately after intervention and at 3 months follow-up. In both groups pain and functional disability were significantly reduced following treatment (p<0.01), but no significant difference was found between the two groups (p>0.05). All measurements were improved in both groups (p<0.01) although patients in the experimental group showed greater improvement in PFM strength and endurance (p<0.01). It seems that the PFM exercise combined with routine treatment was not superior to routine treatment alone in patients with chronic LBP.

The prevalence of low back pain in Iranian dentists: An epidemiological study

Objective: Low back pain (LBP) is one of the most common and prevalent work-related conditions. The aim of this study was to estimate the prevalence and risk factors associated with LBP in dentists and to analyze the association between individual and occupational characteristics and LBP. Methods: Following ethical approval, 300 dentists from Tehran Iran have voluntarily participated. Different questionnaires were completed to collect personal, occupational characteristics and the prevalence and risk factors of LBP. Visual analogue scale and Oswestry disability questionnaires were used to determine pain intensity and level of functional disability. Results: The results indicated that point, last month, last six month, last year and lifetime prevalence of LBP were 24.6%, 24.9%, 27.7%, 28.1% and 31.4%, respectively. A significant correlation was found between the prevalence of LBP and preventive strategies, general health condition, having an assistant and job satisfaction. Body mass index, age and gender were not significantly correlated with the prevalence of Low back pain Conclusions: The prevalence of Low back pain in dentists appears to be high. Further studies focusing on the effectiveness of different preventive strategies are recommended.

Multifidus muscle size in adolescents with and without back pain using ultrasonography

OBJECTIVE The purposes of this study were; a) to compare multifidus muscle cross sectional area (CSA) in male adolescents suffering from low back pain (LBP) with healthy male adolescents using ultrasonography (US), and b) to assess the correlation between multifidus muscle size and demographic variables. METHODS A random sample of 40 healthy boys (as a control group) and 40 boys with LBP (as an experimental group) at the age range of 15-18 years was recruited in the present cohort study. Multifidus muscle dimensions including CSA, antero-posterior and medio-lateral dimensions were measured at level of L5 in both groups using US. RESULTS The results of an independent t-test to compare multifidus muscle size between the experimental and control groups showed a significant difference between the two groups in terms of CSA, antro-posterior and medio-lateral dimensions so that the experimental group had smaller muscle size than the control group. A significant correlation was found between height, weight and body mass index (BMI) and multifidus muscle size, but no significant correlation was observed between age and muscle size. Pain intensity and functional disability index was significantly correlated with muscle size in the experimental group. CONCLUSIONS According to the results, multifidus muscle size was decreased in 15-18 years old male adolescents suffering from LBP compared with their healthy counterparts. Further studies are needed to support the findings of the present study.

Normal values of abdominal muscles thickness in healthy children using ultrasonography

Abdominal muscles are one of the important elements to support the lumbar spine. Evaluation of muscle thickness using ultrasonography (US) is considered to be a source of information from muscles characteristics. The purpose of this study was to demonstrate normal reference data of abdominal muscles thickness and subcutaneous fat in adolescents using US. A random sample of 160 healthy adolescents (80 boys and 80 girls) at the age range of 15-18 years was recruited. Three abdominal muscles including Transversus Abdominis (TA), Internal Oblique (IO), External Oblique (EO) and subcutaneous fat (SF) were bilaterally measured using US. The range of normal values for TA muscle thickness was between 2.31 and 2.57 mm, for IO muscle thickness was between 4.02 and 5.15 mm and for EO muscle thickness was between 2.81 and 3.17 mm. The normal patterns of abdominal muscles were found as IO > EO > TA at both sides. Boys were taller, heavier with greater body mass index (BMI) and had larger abdominal muscles thickness than girls. A weak negative correlation was found between age and muscles size [r = (-0.06) - (-0.23), p < .05], but a significant positive correlation was found between BMI and muscle size (r = 0.21-0.68, p < .05). It seems that abdominal muscles thickness in adolescents followed the same pattern of muscle size in adults. BMI appeared to be the best predictor of muscle thickness. However, further studies are recommended to support the findings of the present study.

Comparative Study of Abdominal Muscle Thickness on Ultrasonography in Healthy Adolescents and Patients With Low Back Pain

Low back pain (LBP) is a common musculoskeletal disorder among different age groups, including adolescents. The purpose of this study was to compare the abdominal muscle thickness between healthy adolescents and those with LBP.

Reliability of sonography in the assessment of lumbar stabilizer muscles size in healthy subjects and patients with scoliosis

OBJECTIVE The purpose of the present study was to compare the reliability of sonography in the evaluation of abdominal and multifidus muscles size between healthy subjects and patients with scoliosis. METHODS In this study, 20 healthy males and 20 male patients with scoliosis (20-50 years old) were recruited. Multifidus and abdominal muscles (transversus abdominis, internal and external oblique) size were assessed by sonography. Three images were recorded; the first and second images were taken on the same day with an hour interval to evaluate within-day reliability, and the third image was taken one-week later to assess between-day reliability. RESULTS Intraclass correlation coefficient (ICC = 0.82-0.91) demonstrated high within-day reliability of sonography in the assessment of abdominal muscle thickness in both groups. In addition, high between-day reliability was observed for these muscles in both healthy and patient groups (ICC = 0.80-0.89). Within-day and also between-day reliability of multifidus muscle were shown to be high in the healthy group (ICC = 0.81-0.88) and the patient group (ICC = 0.78-0.85). Overall, within-day reliability was higher than between-day reliability and also the reliability of sonography in healthy subjects was greater than of those suffering from scoliosis. CONCLUSIONS According to the results, sonography was shown to be a highly reliable imaging technique for assessment of abdominal and multifidus muscle size in healthy males and those suffering from scoliosis.