Myotonometric Measurements Research Articles

Myotonometric assessment of peroneus longus muscle mechanical properties during contraction in athletes with and without chronic ankle instability

Our recent findings in athletes with chronic ankle instability (CAI) revealed increased tone and stiffness alongside reduced elasticity in the peroneus longus (PL) during myotonometric (MYO) measurements at rest, suggesting diagnostic relevance. MYO recordings during muscle contraction in healthy subjects showed an active muscle stiffness influence on MYO parameters, suggesting its potential impact on CAI-related MYO findings. However, it remains unknown whether PL stiffening observed recently in CAI athletes at rest can also be detected while PL muscle contraction. This study, using myotonometry, examines the PL mechanical properties during a motor task mimicking PL’s biomechanical function, i.e., simultaneous isometric foot pronation and plantar flexion (IFPPF) at 30 % and 100 % of maximal voluntary contraction (MVC) in athletes with CAI. Nineteen adult male athletes with CAI (per International Ankle Consortium criteria) and 19 control (CO) athletes without lateral ankle sprain incidents comprised the study groups. Both groups had similar anthropometric parameters and training volume. Simultaneous force and MYO measurements were performed at 30 % and 100 % of MVC-IFPPF, using a MyotonPRO® device. Five MYO parameters were recorded in the PL: frequency, stiffness, decrement, relaxation time, and creep. No significant inter-group differences were observed in MYO parameters and force values measured during the 30 % and 100 % of MVC-IFPPF. This study, employing myotonometry, is the first to demonstrate the lack of significant differences between CAI and CO athletes in the MYO parameters measured in the PL muscle at submaximal and maximal contraction during simultaneous IFPPF, contrasting with our previous MYO results in CAI at rest.

Dose Escalation Can Enhance the Therapeutic Potential of Radial Extracorporeal Shock-Wave Therapy in the Treatment of Plantar Fasciitis in Runners.

Background and Objectives: Treatment of chronic plantar fasciitis is challenging given that there are various of available treatment options with no clear gold standard. The aim of the study was to examine the dose-escalation effect of rESWT on the biomechanical parameters of the plantar fascia and pain ailments. Materials and Methods: In the experimental group (n = 30), the intensity of the shock wave was increased every two subsequent treatment sessions. In the control group (n = 32), the treatment parameters were not changed. In both groups, six treatments were performed, with two treatment sessions a week. In order to assess the biomechanical parameters of the plantar fascia, myotonometric measurements were performed. The pain intensity was assessed using the Visual Analog Scale (VAS). Results: The tension of the plantar fascia attachment in the experimental group decreased from 27.69 ± 2.06 [Hz] before treatment to 26.29 ± 1.69 [Hz] after treatment (p = 0.009) and to 26.03 ± 2.15 [Hz] 1 month after the beginning of treatment (p = 0.003). In the control group, the frequency results did not change significantly (p > 0.05). Flexibility increased in both groups. The test results before treatment and 1 month after the beginning of the treatment showed statistical significance in the experimental group (p = 0.001) vs. (p = 0.002) in the control group. The differences were not statistically significant between groups (p > 0.05). The assessment of pain intensity carried out 1 month after the end of treatment in the experimental group amounted to 3.14 ± 2.28 points, which was statistically significantly lower compared to that in the control group, where it amounted to 5.14 ± 1.92 points. (p < 0.001). Conclusions: The use of rESWT performed with an increasing intensity of impact during subsequent treatment procedures demonstrated greater effectiveness in improving the biomechanical parameters of the plantar fascia and was also more effective in reducing the pain ailments. Our results are encouraging. The dose escalation in the treatment cycle is worth considering. To prove that this method of treatment is more effective, a randomized controlled trial should be carried out on a representative sample.

Mechanical properties of the patellar tendon in weightlifting athletes - the utility of myotonometry. Adaptations of patellar tendon to mechanical loading.

Purpose: Tendons adapt to loads applied to them, by changing their own mechanical properties. The purpose of the study was to examine the influence of practicing sport in the form of weightlifting/strength training by individuals of various age groups upon the mechanical properties of the patellar tendon. Methods: 200 people participated in the study. Group 1 (n = 109) comprised individuals training strength sports as amateurs, group 2 (n = 91) consisted of people who were not physically active. The patellar tendon was examined in various positions of the knee joint: 0, 30, 60, 90, 120° respectively. The following mechanical parameters were measured with the use of a device for myoto-nometric measurements, MyotonPRO: frequency [Hz], stiffness [N/m], decrement [log], relaxation time [ms] and creep [De]. The results were compared as regards physical activity, training history, BMI value, and gender. Results: Stiffness and tone increased while elasticity decreased with patellar tendon stretching degree. In the group of individuals in training, greater stiffness and tone and lower elasticity were noted. Moreover, stiffness and tone appeared to be higher in elderly people and individuals with longer training experience. Conclusions: Mechanical loads connected with strength training result in development of adaptive changes in the patellar tendon, in the form of higher stiffness and tone, as well as lower elasticity. The MyotonPRO device is useful for quantitative assessment of the mechanical properties of patellar tendon.

Relationship between morphometric and mechanical properties of superficial lumbosacral soft tissue layers in healthy young adults.

Introduction: It is commonly considered that myotonometry is a non-invasive method capable of quantifying linear elastic and viscoelastic properties of the myofascial tissue through the application of a weak mechanical impulse to the surface of the skin. However, before the impulse can reach the myofascial tissue, it must cross more superficial tissues such as the skin and subcutaneous tissue (ST). All these superficial tissues have different distributions and organizations of structural components. Therefore, the study aimed to examine the potential relationships between the mechanical and morphometric properties of various superficial soft tissues surrounding the lumbar multifidus muscle (LM). Methods: Myotonometric measurements of dynamic stiffness, logarithmic decrement, and creep, and ultrasonographic measurements of thickness and echogenicity of cutaneous, subcutaneous, perimuscular tissue, and LM were obtained from 50 healthy individuals in the resting prone position and during contralateral arm lift. Results: The most important findings were that in both the relaxed and contracted LM state, the dynamic stiffness strongly negatively (r = -0.69; p < 0.001 in relaxation, r = -0.83; p < 0.001 in contraction) and creep strongly positively (r = 0.79; p < 0.001 in relaxation, r = 0.85; p < 0.001 in contraction) correlated with the thicknesses of the ST. Similar but weaker correlations were noticed between both these measures and the perimuscular tissue thickness. Elasticity was uncorrelated to the thicknesses of the tissues. With LM contraction (change from the relaxed to contracted state), the relative increase in dynamic stiffness was correlated with the relative decrease in dermis (r = -0.51; p < 0.001) and ST (r = -0.47; p = 0.001) thickness, and with the relative increase in LM (r = 0.36; p = 0.010) thickness. Moreover, the relative decrease (thinning) in the ST thickness was correlated with the relative increase in logarithmic decrement (i.e., decrease in soft tissue elasticity, r = -0.37, p = 0.011). The mechanical properties of the soft tissues were not related to their echogenicity. Discussion: In conclusion, the thicker the subcutaneous and perimuscular layers, the lesser the stiffness and the greater the time-dependent deformation to the external force of the tissues surrounding the LM during its relaxation and isometric contraction. Moreover, the greater the thinning of the ST and the thickening of the LM during its contraction, the higher the increase in lumbosacral tissue stiffness and the decrease in elasticity. Therefore, one should consider the thickness of the ST before planning or analyzing the outcomes of myotonometric or other external biomechanical measurements to avoid drawing the wrong conclusions about the mechanical properties of the myofascial tissue.

Myofascial Trigger Points therapy decreases myotonometric tone and stiffness of trapezius muscle, benefits headaches and muscle pain in migraine.

Migraine is a primary headache disorder. Studies have shown that 93% of people with migraine have an increased number of active Ischemic Compression Myofascial Trigger Points (IC-MTrPs) therapy. To examine the effects of the IC-MTrPs therapy on: (1) mechanical properties of the upper trapezius muscle (UTM), (2) shoulder girdle and neck (SGN) muscles pain and (3) headaches characteristics in episodic migraine patients without aura. Thirty-one adult, female, migraine patients without aura underwent seven IC-MTrPs therapy sessions and were tested during maximally five measurement sessions (pre- and post-1'st, post-4'th, post-7'th therapy and 1-month follow-up). Myotonometric measurements of the UTM's tone, stiffness and elasticity, subjective SGN muscles pain, as well as headache's level, frequency and duration were analyzed. Myotonometric tone and stiffness of the UTM significantly decreased in post-1'st, post-4'th therapy and in 1-month follow-up measurements versus pre-1'st therapy testing session. The scores for the SGN muscles' pain significantly decreased: (i) in post-4'th and post-7'th therapy versus post-1'st therapy session, and (ii) in post-7'th versus post-4'th therapy measurements. Headache's level, frequency and duration significantly decreased in post-7'th therapy versus pre-1'st therapy measurement session. IC-MTrPs therapy resulted in a decrease of upper trapezius muscle tone and stiffness, with simultaneous alleviation of shoulder girdle and neck muscle pain and the headaches characteristics in episodic migraine patients without aura.

Heightened tone and stiffness with concurrent lowered elasticity of peroneus longus and tibialis anterior muscles in athletes with chronic ankle instability as measured by myotonometry

In a recent study, myotonometry revealed adverse alterations in the mechanical properties of ankle periarticular muscles in soldiers reporting previous lateral ankle sprain (LAS) incidents. This knowledge, if confirmed in athletes with developed chronic ankle instability (CAI), may have important diagnostic and therapeutic implications in sports medicine and rehabilitation.Consequently, the purpose of the study was to explore mechanical properties of the peroneus longus (PL), tibialis anterior (TA), and the lateral and medial gastrocnemius (LG and MG, respectively) muscles in athletes suffering CAI.Fourteen adult male athletes with developed CAI (International Ankle Consortium selection criteria) and 15 healthy male athletes without any LAS incidence as the control group (CO) participated in the study. The CAI and CO groups were characterized by similar anthropometric parameters and weekly training volume. In both the groups of athletes, we performed resting state (controlled with electromyographic recordings) myotonometric measurements (using a MyotonPRO® device) in the PL, TA, LG and MG muscles and calculated the following five myotonometric parameters: frequency (F-MYO), stiffness (S-MYO), decrement (d-MYO), relaxation time (R-MYO) and creep (C-MYO).Athletes from the CAI group (compared to the CO group) exhibited significantly higher values of F-MYO and S-MYO as well as lower values of R-MYO and C-MYO in the PL and TA muscles. No significant inter-group differences were found in the remaining myotonometric parameters.Using myotonometry, our study is the first to reveal that athletes with developed CAI are characterized by heightened tone and stiffness with concurrent lowered elasticity of the PL and TA muscles.

Effect of Rounded and Hunched Shoulder Postures on Myotonometric Measurements of Upper Body Muscles in Sedentary Workers

Background: Shoulder pain is prominent among sedentary employees who make motions of the upper limbs on a regular basis. Rounded shoulder posture (RSP) and hunched shoulder posture (HSP) are the most common clinical postural misalignments. These causes the spine to bend and raise tension on the nerve roots, which has a negative impact on upper-extremity muscular strength and function. Therefore, this study was carried out to investigate the effect of RSP and HSP on the mechanical parameters of the upper body muscles in clinically asymptomatic sedentary workers. Methods: Twenty office workers with RSP, 20 with HSP, and 20 with normal shoulder posture (NSP) were matched for age, BMI, and type of job. Volunteers were split into groups based on photometric shoulder angle measurements. Mechanical properties such as muscle tone, stiffness, and elasticity of the upper trapezius, middle trapezius, posterior deltoid, and pectoralis major were assessed in sedentary postures. Results: The study revealed a significant decrease in muscle tone for the pectoralis major and a significant increase in muscle stiffness for the poster deltoid in both RSP and HSP as compared to NSP. Specifically, muscle tone decreased from 20.1 ± 4.0 to 12.4 ± 3.1 Hz (38.3%), (p ≤ 0.001) in RSP and from 20.1 ± 4.0 to 14.0 ± 4.8 Hz (30.3%), (p ≤ 0.001) in HSP. Muscle stiffness increased from 309.9 ± 70.7 to 348.15 ± 68.7 N/m (11%), (p ≤ 0.001) in RSP and from 309.9 ± 70.7 to 441.7 ± 45.9 N/m (29.8%), (p ≤ 0.001) in HSP. Conclusions: RSP and HSP have an impact on the tone, stiffness, and elasticity of upper body muscles in healthy asymptomatic sedentary workers. These postures, on a regular basis, may affect physical health and decrease workers’ productivity. In addition, it is recommended for sedentary workers to take regular breaks and attend training that could help improve their physical health.

Effect of local muscle fatigue on biomechanical and viscoelastic properties of skeletal muscles

The work is devoted to the study of the effect of local muscle fatigue on the biomechanical and viscoelastic properties of skeletal muscles. A device for non-invasive digital palpation MyotonPRO was used to carry out myotonometric measurements. The study involved 13 males and females (6 males and 7 females) aged 32.5 ± 10.6 years. Each volunteer completed two series of exercises that induce local muscle fatigue of the hand muscles. The exercises were performed with a hand grip with a resistance of 20 kg. The first series of exercises was performed until the volunteer developed a subjective fatigue, the second - until his/her refusal to continue due to excessive fatigue of the hand muscles. Testing had 3 stages: before starting strength exercises, after exertion, before subjective fatigue, and after loading with maximal exertion. Local muscle fatigue was objectively confirmed by dynamometry in accordance with the physiology standards. Myotonometry was performed on the cubital and radial flexors of the carpus, and on the abductor thumb muscle. As a result of the statistical analysis of data, it was shown that the myotonometry can be used to diagnose muscle fatigue. A change in active muscles myotometric indicators can be registered even when a subjective fatigue occurs, while local muscle fatigue does not affect the change in the tone of inactive muscles. It was also shown that the location of the measurement point of myotonometric characteristics on the muscle belly of the cubital flexor of the carpus does not affect the results with the condition that the place of application of the device is within the range of ± 2 cm from the center of the muscle belly.

Effects of Dry Needling on Biomechanical Properties of the Myofascial Trigger Points Measured by Myotonometry: A Randomized Controlled Trial

ObjectiveThe purpose of the present study was to examine the effect of dry needling (DN) on the biomechanical properties of a latent medial myofascial trigger point (MTrP) of the soleus muscle compared with an adjacent point within the taut band (TB) measured by myotonometry. MethodsFifty asymptomatic volunteers were randomly assigned to an intervention group (n = 26) or control group (n = 24). One session of DN was performed in every group as follows: 10 needle insertions into the MTrP area (intervention group) or TB area (control group). Myotonometric measurements (frequency, decrement, and stiffness) were performed at baseline (pre-intervention) and after the intervention (post-intervention) in both locations (MTrP and TB areas). ResultsThe results showed that stiffness outcome significantly decreased with a large effect size after DN in the MTrP when measured in the MTrP location (P = .002; d = 0.928) but not when measured in the TB location. In contrast, no significant changes were observed in any location when the TB was needled (P > .05). ConclusionsThe findings suggest that only DN into the MTrP area was effective in decreasing stiffness outcome, therefore a specific puncture was needed to modify myofascial muscle stiffness.

Investigating the effects of head posture muscles’ viscoelastic parameters on pulmonary and functional capacity in healthy individuals

IntroductionForward head posture (FHP) is known to have a large influence on respiratory function by weakening the respiratory muscles. This cross-sectional study is designed to examine the relationship between the tonus, stiffness, and elasticity of head posture muscles and pulmonary capacity.MethodsOverall, 16 FHP and 17 non-forward head posture (NFHP) individuals were evaluated. The tonus, stiffness, and elasticity of the upper trapezius, semispinalis capitis, pectoral muscles, and sternocleidomastoid muscles were measured with a MyotonPRO® device. Functional capacity was assessed with the 6-minute walk test. Pulmonary function tests employed a spirometer. The Neck Disability Index was applied. FHP was determined by measuring the craniovertebral angle. Physical activity levels were evaluated with the Physical Activity Index.ResultsThe study involved 18 (54.54%) female and 15 (45.45%) male students. Their mean age was 21.24 ± 1.82 years. Neck Disability Index scores were higher in participants with FHP than in NFHP individuals (&lt;i&gt;p&lt;/i&gt; = 0.037). There were no significant differences in the myotonometric measurements of the analysed muscles between FHP and NFHP groups (&lt;i&gt;p&lt;/i&gt; &gt; 0.05). Physiological characteristics of FHP and NFHP participants were different in terms of vital capacity, forced vital capacity, forced expiratory volume in 1 second, and peak forced expiratory volume (&lt;i&gt;p&lt;/i&gt; &lt; 0.05).ConclusionsOwing to the pulmonary capacity differences between FHP and NFHP individuals, it can be concluded that FHP affects pulmonary capacity. Also, pectoral muscles and semispinalis capitis muscles play an important role in thoracic expansion and therefore influence vital capacity.

Assessment of the mechanical characteristics of the lower extremity muscles with myotonometric measurements in healthy individuals

IntroductionThis study aimed to establish normative values for stiffness, tone, and elasticity of lower extremity muscles and to determine age and sex differences.MethodsOverall, 389 participants (199 females, 190 males) were included. The mechanical properties of the tibialis anterior (TA), rectus femoris (RF), vastus lateralis (VL), vastus medialis obliquus (VMO), gastrocnemius lateralis (GL), and gastrocnemius medialis (GM) muscles were assessed bilaterally with the MyotonPRO device. The data were compared with respect to sex and age.ResultsThe mechanical properties were significantly higher bilaterally in males than females in all parameters (&lt;i&gt;p&lt;/i&gt; &lt; 0.05). Right TA stiffness and elasticity, GM tone and stiffness were higher than left in females (&lt;i&gt;p&lt;/i&gt; &lt; 0.05). Greater VMO elasticity and RF tone were found in left vs. right (&lt;i&gt;p&lt;/i&gt; &lt; 0.05). Right GL-VL stiffness and elasticity were greater than left in males (&lt;i&gt;p&lt;/i&gt; &lt; 0.05). VMO-RF tones were bigger in left compared with right (&lt;i&gt;p&lt;/i&gt; &lt; 0.05). Among age groups, right-left TA tone and stiffness were greater in group 1 (18–28 years old) (&lt;i&gt;p&lt;/i&gt; &lt; 0.05). Right-left VL-VMO tones, and left RF stiffness and tone were lower in group 2 (29–39 years old) (&lt;i&gt;p&lt;/i&gt; &lt; 0.05). Right GM-VMO stiffness, right-left TA-GL-GM-VMO and RF elasticity were greater in group 3 (40–50 years old) compared with others (&lt;i&gt;p&lt;/i&gt; &lt; 0.05).ConclusionsThe mechanical properties of leg muscles were bilaterally higher in males. Different characteristics were observed of different muscles for both sexes. GL-GM-VMO-RF elasticity decreased, and TA stiffness and VMO tone increased with advancing age in both legs

Influence of Forward Head Posture on Myotonometric Measurements of Superficial Neck Muscle Tone, Elasticity, and Stiffness in Asymptomatic Individuals With Sedentary Jobs

ObjectiveThe objective of the study was to assess the influence of forward head posture on the mechanical parameters and pressure pain threshold of superficial neck muscles in clinically nonsymptomatic individuals with sedentary jobs. MethodsTwenty-five office workers with forward head posture and 25 office workers with normal head posture were matched for sex, age, body mass index, and the nature and duration of their work and were compared at a single point. The study participants were divided into study groups on the basis of photometric craniovertebral angle measurements. The upper trapezius, sternocleidomastoid, and splenius capitis mechanical properties were assessed in the sitting position. Primary outcome measures were muscle stiffness (N/m), muscle tone (Hz), and muscle elasticity. The secondary variable was perceived pain threshold. ResultsNo significant differences between the groups were found for biomechanical properties and perceived pain threshold in the studied muscles. ConclusionForward head posture has no impact on muscle stiffness, tone, and elasticity, nor does it increase the pressure sensitivity of superficial neck muscles in healthy, mildly symptomatic office workers. It is most likely that not incorrect posture of the cervical spine, but probably other factors combined with forward head posture, like comorbid acute and chronic cervical pain and musculoskeletal disorders or prolonged sitting, contribute to changes in active myofascial tone and tensegrity as well as increased pressure sensitivity of neck muscles.

Patellar and Achilles Tendon Stiffness in Elite Soccer Players Assessed Using Myotonometric Measurements.

Background:Tendon overuse injuries are an issue in elite footballers (soccer players) and may affect tendon function. Achilles and patellar tendinopathy are the most frequent pathologies. Tendon stiffness, the relationship between the force applied to a tendon and the displacement exerted, may help represent tendon function. Stiffness is affected by training and pathology. Nevertheless, information regarding this mechanical property is lacking for elite soccer athletes.Hypothesis:Achilles and patellar tendon stiffness assessed using myotonometric measurements will be greater in elite soccer athletes than in control participants.Study Design:Cross-sectional study.Level of Evidence:Level 4.Methods:Forty-nine elite soccer athletes and 49 control participants were evaluated during the 2017 preseason. A handheld device was used to measure Achilles and patellar tendon stiffness. Dominant and nondominant limbs were assessed for both groups.Results:A significantly stiffer patellar tendon was found for both the dominant and the nondominant limb in the elite soccer athletes compared with the control group. Nevertheless, no differences were found in Achilles tendon stiffness between groups. When comparing between playing positions in soccer athletes, no significant differences were found for both tendons.Conclusion:Greater patellar tendon stiffness may be related to an improvement in force transmission during muscle contraction. On the other hand, it seems that after years of professional training, Achilles tendon stiffness does not change, conserving the storing-releasing function of elastic energy. The nonsignificant differences between positions may be attributable to the years of homogeneous training that the players underwent.Clinical Relevance:The present study shows another technique for measuring mechanical properties of tendons in soccer athletes that could be used in clinical settings. In the future, this technique may help clinicians choose the best exercise protocol to address impairments in tendon stiffness.

Myotonometry as a measure to detect myofascial trigger points: an inter-rater reliability study

Objective: Several diagnostic methods have been used in the identification of mechanical properties of skeletal muscle, including myofascial trigger points (MTrPs), however, they are not suitable for daily clinical use. Myotonometry offers an easy noninvasive alternative to assess these muscle properties. Nevertheless, previous research has not yet studied the mechanical properties of MTrPs by myotonometry. The purposes of this study were (1) to analyze the differences in the mechanical properties between latent MTrPs and their taut bands by myotonometry, (2) to investigate the inter-rater reproducibility of myotonometric measurements, and (3) to examine the association between myotonometry and passive isokinetic dynamometry. Approach: Fifty individuals (58% male; age 24.6 ± 7.9 years) with a latent medial MTrP of the right soleus muscle participated. The mechanical properties of this MTrP area of soleus muscle and its taut band area were measured using a myotonometer (MyotonPRO). Additionally, passive resistive torque and extensibility of triceps surae muscle were assessed using a Kin-Com dynamometer. Main results: Statistical analysis indicated higher values for the stiffness parameter in the taut band with respect to the MTrP (P < 0.05). The inter-rater reliability of the myotonometric measurements was good for all variables (ICC3,1 > 0.75). The standard error of measurement (SEM) and minimal detectable difference (MDD) indicated a small measurement error for frequency and stiffness variables (SEM% < 10%; MDD95% < 20%). Significant fair correlations between myotonometric parameters and passive isokinetic parameters ranged from −0.29 to 0.48 (P < 0.05). Significance: The myotonometer was demonstrated to be a reliable tool and was able to quantify differences in the mechanical properties of myofascial tissues. The potential of this method for the assessment of myofascial pain syndromes requires further investigation.

Measuring Muscle Fatigue in Relation to the Workload of Health Care Workers

Number of work related musculoskeletal disorders due to ergonomics risks among workers in Europe, including Latvia, is growing. Employees in health care professions admit physical load and discomfort in various body parts after the shift. According to Eurostat statistical data 60% of total work related diseases are attributed to musculoskeletal disorders in Latvia. The aim of this study was to determine the muscle fatigue caused by physical load for surgeons, anaesthetists and geneticists in one of the largest Hospitals in Latvia. The research involved 9 surgeons, 9 anaesthetists and 7 geneticists with chronic pain (for four months or more) in the neck, shoulders, arms, hands and legs. All of them agreed to take part in myotonometric measurements. The main results included NMQ-E inquiry data analysis and proved that all participants most frequently complain of feeling discomfort after work, particularly, fatigue or muscle pain in the neck, shoulders, arms, hands and legs. Myotonometric measurement results show that geneticists’ muscle tone at the end of the working week has increased in the shoulder region muscles and slightly in wrist/hands muscles (m. extensor digitorum; m. flexor carpi radialis). Muscle tone of the surgeons increased in wrist, hand and shoulder region, as well as in legs at the end of the working week: m. flexor carpi radialis; m. tibialis anterior; m. gastrocnemius (caput mediale), but anaesthetists’ muscle tone increased in shoulder region and in legs. Hence research participants (surgeons, anaesthetists, geneticists) are subjected to long and intensive work in compulsory work positions, which has impact on fatigue of various muscle groups.

Reliability and Asymmetry Profiles of Myotonometric Measurements in Healthy Skeletal Muscles

Background: Myotonometric measurement provides information about the muscle properties before and after applying physiotherapy treatments. This study examined the reliability, the degree of side-to-side symmetry, and the muscle type effect of the myotonometric parameters. Methods: Bilateral muscle stiffness, oscillation frequency and decrement of 11 different muscles during relaxed state were measured on 14 healthy male participants using a myometer over two consecutive days. Within-day and inter-day intraclass correlation coefficients (ICC) and absolute symmetry index (ASI) of measurements on each muscle site were calculated. Comparisons were made between the two muscle types and among the different test parameters. Results: Muscle decrement had significantly lower within-day ICC than muscle stiffness (P 20%) in the decrement measurement. Conclusion: Myotonometric measurements are generally reliable for clinical muscle assessment. In analyzing and interpreting myotonomeric measurements, assessing muscle asymmetries should consider if the observed difference is due to measurement errors or intervention effects when involving such parameters and muscles.

Quantitative Assessment of Normal Tissue Elasticity by ARFI Shear-Wave Ultrasound Elastography and MyotonPro Myometry measurements of the Thoracolumbar fascia (TLF) - A Comparison of both techniques

Purpose: Fascia play an important role for the complex interplay of muscle function and neuromuscular transmission of information and in the development of myofascial pain. The new ultrasound based technology Acoustic Radiation Force Impulse Virtual Touch Imaging and Quantification (ARFI VTIQ), and myotonometric measurements (MyotonPro) can both assess quantitative tissue characteristics like stiffness of tissues.

The effects of a medical hypnotherapy on clothing industry employees suffering from chronic pain

BackgroundProblems associated with pain in several body regions due to work-related musculoskeletal disorders (WRMDs), repetitive movement and negative stress at work are quite common in many manufacturing industries of Latvia, int.al. clothing industry. The aim of this study was to evaluate efficiency of the psychotherapeutic intervention using medical hypnotherapy (MH) program for mind-body relaxation with pain-blocking imagery, cognitive restructuring of unpleasant physical and emotional experience.Methods300 sewers and 50 cutters with chronic pain were involved in the study. Self-rated WRMDs symptoms, pain intensity and interference were assessed using the extended version of Nordic Musculoskeletal Questionnaire and Brief Pain Inventory Scale. Assessment of the functional state of muscles was carried out using myotonometric (MYO) measurements. Work heaviness degree was estimated via heart rate monitoring (HRM). The MH program was composed of cognitive hypnotherapy and self-hypnosis training. Sunnen Trance Scale was used to determine person’s hypnotic susceptibility. Life quality assessment before and after MH program was carried out using Quality of Life Scale.ResultsAt the beginning of MH program sessions both sewers and cutters reported on pain interference with general activities, mood, sleep, normal work, etc., but after MH the interference of pain significantly decreased. HRM data confirmed that work heaviness degree of sewers and cutters can be referred to as light and moderate work (energy expenditure for their tasks varies from 3.4 till 4.7 kcal/min). Using MYO measurements it was stated that before MH 22% of workers involved in the study fell under III MYO category indices, consequently, their muscle tone was increased, which is associated with muscular fatigue. After MH muscle tone remained within the normal range meaning that they were able to adapt to the existing workload (II MYO category) or fully relax (I MYO category).ConclusionsMH program including exercises-workouts, cognitive hypnotherapy and self-hypnosis training sessions is an effective method to decrease composite chronic pain intensity for sewers and cutters, as well as to decrease psychogenic tension and muscle fatigue (proved by objective measurements of muscles tone) and to increase the life quality.

Relative and Absolute Reliabilities of the Myotonometric Measurements of Hemiparetic Arms in Patients With Stroke

ObjectiveTo investigate the relative and absolute reliabilities of the myotonometer. DesignPsychometric study. SettingThree medical centers. ParticipantsPatients with stroke (N=61). InterventionsNot applicable. Main Outcome MeasuresMuscle tone, elasticity, and stiffness of relaxed affected deltoid, triceps brachii, biceps brachii, extensor digitorum, flexor carpi radialis, and flexor carpi ulnaris were measured twice, 30 minutes apart, using the myotonometer. Intraclass correlation coefficient, a relative reliability index, was calculated for 3 muscular properties and for each muscle to examine the degree of consistency and agreement between the 2 test sessions. Absolute reliability indices, including the SEM, smallest real difference, and Bland-Altman limits of agreement, were used to quantify measurement errors and check systematic biases of the 2 test sessions. ResultsThe intraclass correlation coefficients were .83 to .95 for muscle tone, elasticity, and stiffness of all muscle groups. The SEM and the smallest real difference of muscle tone, elasticity, and stiffness of the biceps were the smallest among the 6 muscles tested. The Bland-Altman analyses showed no systematic bias between most of the repeated measurements. Compared with other muscles, biceps had narrower limits-of-agreement ranges, indicating that the myotonometric measurements of the biceps had higher stability and less variation over time. ConclusionsThe myotonometer reliably measures muscular properties, with good relative and absolute reliabilities. These findings are useful for clinicians and researchers to assess muscle properties reliably and determine whether a real change has occurred in groups and on individual levels of patients with stroke.

Muscle stiffness at different force levels measured with two myotonometric devices

Myotonometric measurements are quantitative methods of muscle tone assessment and may be used as an alternative for palpation evaluation. The objective of the study was to compare the measurements of brachioradialis muscle tone and stiffness using the Myoton-3 and the Myotonometer. The participants were young males (N = 17, mean age 21 ± 1 years). The skeletal muscle state was expressed by the Myoton-3 parameters stiffness (N m−1), frequency (Hz) and decrement (no unit) and the Myotonometer's area under the curve (AUC) parameter (area under the curve, no unit), when muscle was at rest and during activity at 25%, 50%, 80% and 100% of maximal voluntary contraction for elbow flexors. Pearson's correlation between AUC and stiffness is r = −0.89, AUC and frequency r = −0.84 and AUC and decrement r = 0.79, p < 0.01. When comparing the results from each experimental condition separately for frequency and AUC, the correlation was from −0.63 to −0.80, for stiffness and AUC it ranged from −0.25 to −0.75 and for decrement and AUC from 0.27 to 0.74. The degree of correlation between myotonometric measurements depends on whether the measured muscle is at rest or during contraction. The correlation is diverse among related parameters.