Effect of Pelvic Floor Muscle Contraction on Ultrasonographic Thickness of Abdominal Muscles

Introduction: The current study compared the effect of pelvic floor muscle (PFM) contraction on thickness of abdominal muscles during an abdominal hollowing maneuver (AHM), which is a specific contraction of transverse abdominis(TrA)and internal oblique(IO) muscles in healthy and low back pain (LBP) subjects. Materials and Methods: Thirty subjects (15 with LBP and 15 without LBP) participated in this study. In ultrasonographic evaluation, the thickness of the TrA and IO muscles in AHM with and without PFM contraction were measured. Results: No significant difference was seen in the thickness of abdominal muscles in contraction alone and in combination with PFM contraction during AHM between the two groups. No difference was seen in the thickness of abdominal muscles with and without PFM contraction between the LBP and healthy subjects in AHM. Conclusions: Adding PFM contraction had no significant effect on abdominal-muscle contraction in subjects with or without LBP.Keywords: Abdominal muscles thickness, pelvic floor muscles, Ultrasound imag

The Effect of Strengthening Exercises on Functional Ability in Patients with MS: A Review Study

Introduction: Patients with multiple sclerosis (MS) usually report gait and balance disorders. Exercise therapy, especially strengthening exercise, is a safe and effective treatment approach in these patients. Therefore, the aim of this review study was to determine the effect of strengthening exercises on functional ability in patients with MS. Methods and Materials: A search of databases such as PubMed, science direct, Cochrane library, and Google scholar was reviewed to determine the existing articles on the effect of strengthening exercises on functional ability in patients with MS. Results: According to the evaluation of studies from 2000 to 2020, 8 articles met the inclusion criteria. These articles examined the effect of strengthening exercises on functional ability in patients with MS. The results showed that strengthening exercises improved balance variables, functional ability, strength, and quality of life. Conclusion: Various interventions including stretching, balance, strengthening exercises, and electrical stimulation have been used to treat balance disorders, decreased muscle strength, gait efficiency and quality of life in patients with MS. Among these interventions, strengthening exercises have been shown to play an effective role in improving functional ability, although more studies are needed in this area

Measurement of superficial and deep abdominal muscle thickness: an ultrasonography study

BACKGROUND: Real-time ultrasound imaging is a valid method in the field of rehabilitation. The ultrasound imaging allows direct visualization for real-time study of the muscles as they contract over the time. Measuring of the size of each abdominal muscle in relation to the others provides useful information about the differences in structure, as well as data on trunk muscle activation patterns. The purpose of this study was to assess the size and symmetry of the abdominal muscles at rest in healthy adults and to provide a reference range of absolute abdominal muscle size in a relatively large population. METHOD: A total 156 healthy subjects with the age range of 18–44 years were randomly recruited. The thickness of internal oblique, external oblique, transverse abdominis, and rectus abdominis muscles was measured at rest on both right and left sides using ultrasound. Independent t test was used to compare the mean thickness of each abdominal muscle between males and females. Differences on side-to-side thicknesses were assessed using paired t test. The association between abdominal muscle thicknesses with gender and anthropometric variables was examined using the Pearson correlation coefficient. RESULTS: A normal pattern of increasing order of mean abdominal muscle thickness was found in both genders at both right and left sides: transverse abdominis < external oblique < internal oblique < rectus abdominis. There was a significant difference on the size of transverse abdominis, internal oblique, and external oblique muscles between right and left sides in both genders. Males had significantly thicker abdominal muscles than females. Age was significantly correlated with the thickness of internal oblique, external oblique, and rectus abdominis muscles. Body mass index was also positively correlated with muscle thickness of rectus abdominis and external oblique. CONCLUSIONS: The results provide a normal reference range for the abdominal muscles in healthy subjects and may be used as an index to find out abnormalities and also to evaluate the effectiveness of different interventions

Spin dynamics in semiconductors

This article reviews the current status of spin dynamics in semiconductors which has achieved a lot of progress in the past years due to the fast growing field of semiconductor spintronics. The primary focus is the theoretical and experimental developments of spin relaxation and dephasing in both spin precession in time domain and spin diffusion and transport in spacial domain. A fully microscopic many-body investigation on spin dynamics based on the kinetic spin Bloch equation approach is reviewed comprehensively.Comment: a review article with 193 pages and 1103 references. To be published in Physics Reports

Effect of olfactory stimulation on static and dynamic balance in healthy subjects: brief report

Background: The previous studies showed that the odor can improve balance in the elderly. The purpose of the current study was to determine the effect of olfactory stimulus and its gender specific effect on the balance of young healthy people. Methods: This is a pretest-posttest semi experimental study comprised 40 healthy volunteers (age range 18-73 years) from February 2016 through May 2017. The static balance test with one-leg standing time (OLST) and dynamic balance test using Biodex balance system to measure overall stability index (OSI), anterior/posterior stability index (APSI), medial/lateral stability index (MLSI) and overall limit of stability index (OLOSI) randomly were performed before and after application of lavender scant as the olfactory stimuli. A two-way repeated measurement ANOVA was used to assess the effect of olfactory stimulus conditions and gender on dynamic balance indexes (OSI, APSI, MLSI, and OLOSI). Since the distribution of the OLST was not normal, the generalized estimating equations (GEE) method was used. Significance level of P<0.05 was adopted for all comparisons. Means are reported&plusmn;SD unless otherwise stated. SPSS software, version 21 (IBM SPSS, Armonk, NY, USA) was used to carry out all statistical analyses. Results: The results showed that in comparison of the two different conditions (no odor/with odor), there was no significant difference in any of static and dynamic balance indexes (P>0.05). There were significant differences in relation to the interaction of the gender and odor in OSI (P=0.026), APSI (P=0.019). For gender, there were statistically significant differences in OSI (P=0.002, F (1,38) =11.649), APSI (P=0.001, F (1,38) =12.057), and MLSI (P=0.007, F (1,38) =8.228) for females. Conclusion: Although there was no effect of odor on balance control of young healthy people, we found that the odor has gender specific effect. This is probably due to the more sensitivity of females to the odor

The effect of isometric contractions of upper and lower limb muscles on the ultrasonic thickness of the transversus abdominis muscle

Background: The transverse abdominis (TrA) muscle is one of the most important muscles that contribute to the stability of the lumbar spine. Strengthening of trunk muscles that have a significant role in trunk stability is very important in the field of professional sport, sport medicine and rehabilitation of patient with low back pain (LBP). Identifying the exercises that can improve the strength and endurance of these muscles in the efficient way is an important challenge in rehabilitation of LBP patients. The aim of this study was to investigate the effect of maximum voluntary isometric contraction of upper and lower limb muscles on ultrasonic thickness of the TrA muscle. Methods: This is a pre-test post-test study. Thirty healthy young male subjects with mean age of 23 years were recruited from the university staff and student population (non probability sample). Ultrasonic thickness of the right and left TrA muscle (as an indirect measure of muscle activity) was taken at rest and during maximum isometric contraction of six muscle groups: shoulder and hip flexor, extensor and abductor muscles. Mixed-model ANOVA with repeated measures design were used to analyze data. To further analyses post hoc comparisons were performed with paired t-tests adjusted with the Bonferroni method. The significance level was set at P<0.05. Results: The result showed that mean TrA thickness on right and left sides during maximum isometric contraction of the upper and lower limb muscles was significantly thicker than in resting position (P<0.001). The type of isometric contraction had a significant effect on the thickness of the TrA muscle on dominant side (P<0.05). As a result, the greatest change in the thickness of TrA muscle on dominant side was observed in hip isometric extension (P<0.05). There was a significant difference between the thickness of TrA during upper limb isometric contraction of dominant and non-dominant side (P<0.001). Conclusion: Isometric contraction of upper and lower limb muscles especially in hip extension can increase the ultrasonic thickness of the transversus abdominis muscle

The onset and frequency of spasticity after first ever stroke

Spasticity is one of the most important causes of disability after stroke. In spite of high incidence of spasticity, little is known about the relationship between the occurrence and the development of spasticity. This study aimed to determine risk-factors of post stroke spasticity. This was an observational study of 149 persons with first ever stroke. The following parameters were assessed: Stroke severity, Spasticity, Disability and Joint contracture. Prevalence of spasticity was between 17–25% during the first 3 months after stroke. The onset of spasticity was 13.79% and 4.16% at 1 and 3 months after stroke respectively. The prevalence of spasticity in the upper extremity was significantly more than lower extremity at 1 month. Spasticity was significantly more severe in the upper extremity than lower extremity. In patients with hemorrhagic stroke Odds ratios of spasticity was 2.5 times more than persons with ischemic stroke (P = 0.0210. The Odds ratios of severe spasticity at 1 and 3 months were 1.66 and 1.75 times more than the first week (P = 0.024, P = 0.042 respectively). Post stroke spasticity is more common in persons with hemorrhagic stroke, severe paresis and lower functional abilities. The most incidence of spasticity happens in the first month after stroke

Electromyography Activity of the Abdominal Muscles Relative to the Active Pelvic Floor Muscle Contraction in Low Back Pain and Healthy Individuals

Introduction: The purpose of present study was to compare electromyography activity of the abdominal muscles in response to the active pelvic floor muscle contraction in individuals with and without low back pain (LBP). Methods: A total of 30 female subjects (LBP=15) and (healthy=15) participated in the study. All subjects performed the active PFM contraction for three times. The correct pelvic floor muscle contraction was controlled by an ultrasound. Simultaneously, the electromyography signals of the right transverse abdominis, internal oblique and external oblique muscles were measured. Variables of electromyography amplitude were analyzed using an independent sample T-Test. Results: There was a high intra-tester reliability for electromyography measurement of abdominal muscle in LBP (ICC&gt;90) and healthy individuals (77&lt;ICC&lt;96). Transverse abdominis, internal oblique and external oblique muscle electromyography activity were increased during the pelvic floor muscle contractions in both women group with and without low back pain. The results of independent sample T-Test displayed no statistically significant difference in muscle co-activation pattern of the abdominal and pelvic floor muscles between the healthy group and LBP group (P&gt;0.05). The mean values for muscle electromyography amplitude in transverse abdominis, internal oblique and external oblique muscle were 0.37(0.41), 0.18(0.14) and 0.16 (0.10), respectively, for healthy individuals and 0.25 (0.17), 0.13 (0.19) and 0.18 (0.17) for individuals with LBP. Conclusion: There is a recognizable co-activation between abdominal and pelvic floor muscles in healthy and low back pain women.Keywords: Pelvic Floor Muscles, Abdominal Muscles, Low Back Pain, Electromyograph

Reliability of Eelectromyography of Abdominal Muscles During Abdominal Manoeuvre with and without Pelvic Floor Muscle Contraction

Objective: The purpose of this study was to determine the reliability of electromyography measurements of abdominal muscles activity during different manoeuvres (pelvic floor muscle (PFM) contraction, abdominal hollowing and abdominal bracing with and without PFM contraction) in subjects with and without chronic low back pain (LBP). Materials & Methods: In this methodology research 21 subjects (9 with LBP, 12 without LBP) who were selected simply & conveniently participated in the study. Abdominal muscle activation amplitude was assessed. Each maneuver was performed in triplicate and repeating of the test was done on the same day with a period of at least 30 minutes. Data were analyzed by Kolmogroff–Smirnoff test and Interclass correlation coefficient. Results: The results showed high reliability for the muscle activation amplitude during abdominal hollowing with and without pelvic floor muscle contraction and isolation pelvic floor muscle contraction and abdominal bracing (ICC=80–90). Also moderate reliability in abdominal bracing with pelvic floor muscle contraction (ICC=70–80).   Conclusion: Electromyography is a reliable method for assessment of voluntary and automatic activity of abdominal muscles during different conditions