Triceps Surae Research Articles

Short developmental milestone risk assessment tool to identify Duchenne muscular dystrophy in primary care

BackgroundIn patients without a family history, Duchenne muscular dystrophy (DMD) is typically diagnosed at around 4–5 years of age. It is important to diagnose DMD during infancy or toddler stage in order to have timely access to treatment, opportunities for reproductive options, prevention of potential fatal reactions to inhaled anesthetics, awareness of a child’s abilities needed for good parenting, and opportunities for enrolment in clinical trials.MethodWe aimed to develop a short risk assessment tool based on developmental milestones that may contribute to the early detection of boys with DMD in primary care. As part of the case-control 4D-DMD study (Detection by Developmental Delay in Dutch boys with DMD), data on developmental milestones, symptoms and therapies for 76 boys with DMD and 12,414 boys from a control group were extracted from the health records of youth health care services and questionnaires. Multiple imputation, diagnostic validity and pooled backward logistic regression analyses with DMD (yes/no) as the dependent variable and attainment of 26 milestones until 36 months of age (yes/no) as the independent variable were performed. Descriptive statistics on symptoms and therapies were provided.ResultsA tool with seven milestones assessed at specific ages between 12 and 36 months resulted in a sensitivity of 79% (95CI:67–88%), a specificity of 95.8% (95%CI:95.3–96.2), and a positive predictive value of 1:268 boys. Boys with DMD often had symptoms (e.g. 43% had calf muscle pseudohypertrophy) and were referred to therapy (e.g. 59% for physical therapy) before diagnosis.DiscussionThis tool followed by the examination of other DMD-related symptoms could be used by youth health care professionals during day-to-day health assessments in the general population to flag children who require further action.ConclusionsThe majority of boys (79%) with DMD can be identified between 12 and 36 months of age with this tool. It increases the initial a priori risk of DMD from 1 in 5,000 to approximately 1 in 268 boys. We expect that other neuromuscular disorders and disabilities can also be found with this tool.

Teachability of multispectral optoacoustic tomography.

To date, the appropriate training required for the reproducible operation of multispectral optoacoustic tomography (MSOT) is poorly discussed. Therefore, the aim of this study was to assess the teachability of MSOT imaging. Five operators (two experienced and three inexperienced) performed repositioning imaging experiments. The inexperienced received the following introductions: personal supervision, video meeting, or printed introduction. The task was to image the exact same position on the calf muscle for seven times on five volunteers in two rounds of investigations. In the first session, operators used ultrasound guidance during measurements while using only photoacoustic data in the second session. The performance comparison was carried out with full-reference image quality measures to quantitatively assess the difference between repeated scans. The study demonstrates that given a personal supervision and hybrid ultrasound real-time imaging in MSOT measurements, inexperienced operators are able to achieve the same level as experienced operators in terms of repositioning accuracy.

Ferumoxytol-enhanced MR venography for mapping lower-extremity venous networks and evaluating varicose veins in patients with diabetes.

Comprehensive evaluation of lower-extremity varicose veins (VVs) in patients with diabetes is crucial for treatment strategizing. The study aims to assess the feasibility of using ferumoxytol-enhanced MR venography (FE-MRV) for lower-extremity venous mapping and the detection of VVs in patients with diabetes. As part of a phase II clinical trial of a generic brand of ferumoxytol, documented patients with diabetes were enrolled and underwent FE-MRV on a 3-Τ MRI system. Two observers assessed FE-MRV images for image quality, signal intensity ratio (SIR), perforator (PV) diameter, and luminal signal uniformity in deep-to-superficial venous networks with the assessment of intra- and inter-rater reliability. FE-MRV was used to detect lower-extremity VVs. Eleven patients underwent FE-MRV without adverse events. The average image quality, as scored by the two observers who assessed 275 venous segments, was 3.4 ± 0.6. Two observers strongly agreed on image quality (κ = 0.90) and SIR measurements (interclass correlation coefficient [ICC]: 0.72) and had good agreement on PV diameter (ICC: 0.64). FE-MRV revealed uniform luminal signals in deep and saphenous venous networks (0.13 ± 0.05 vs 0.08 ± 0.03). Below-knee segments exhibited a significantly higher heterogeneity index than above-knee (p = 0.039) segments. Superficial VVs were observed in 55% (12/22)of legs in 64% (7/11)of patients. Calf muscle VVs were present in 64% (14/22)of legs in 9 patients. FE-MRV safely and robustly mapped entire lower-extremity venous networks, enabling the detection and pre-treatment evaluation of both superficial, and deep VVs in patients with diabetes. Ferumoxytol-enhanced magnetic resonance venography offers a "one-stop" imaging strategy for the detection and pre-operative evaluation of both superficial and deep VVs in diabetic patients. Diabetic patients with VVs are at a higher risk of ulcer-related complications. FE-MRV allowed rapid and comprehensive visualization of the lower-limb venous networks and abdominopelvic veins in diabetic patients. This technique allowed for the detection of superficial and deep VVs in diabetic patients before the development of severe peripheral artery disease.

Influence of the External Workload on Calf Muscle Strain Injuries in Professional Football Players: A Pilot Study.

The influence of external workload variables on the development of calf muscle strainsin football players has not been previously explored. Overloaded players would have an increased risk of calf muscle strain injury. Prospective observational study. Level 4. A total of 41 professional football players from 1 team were monitored for 2 consecutive seasons. Total distance covered (TD), and distances covered at high-intensity running, high sprint running, low (LACC) and high (HACC) acceleration, low (LDEC) and high (HDEC) deceleration, and at high metabolic load distance (HMLD) were monitored with GPS units. Accumulated players' external workload in the week before injury was compared with the weekly mean value of the 6 weeks before injury occurred for each player. Ten players (24.3%) suffered 16 calf muscle strain injuries (3.1 injuries per 1000 hours of match play; 0.5 injuries per 1000 hours of training exposure). Players with a calf muscle injury were older (p = 0.03), with higher body weight (p = 0.01) and height (p = 0.03). Injured players displayed substantially higher total training volume (p < 0.01), TD (p < 0.01), LACC (p < 0.01), LDEC (p < 0.01), HACC (p < 0.01), HDEC (p < 0.01), and HMLD (p = 0.03) in the week before injury, in comparison with the mean values of these variables in the 6 weeks before injury. A week with a higher-than-habitual external workload might increase the risk of calf muscle strain injury in professional football players. Calf muscle injuries were preceded by a week with unusually high workloads associated with accelerating and decelerating distances and higher training volumes. Monitoring external workload indicators may be helpful in determine players with a higher risk of calf muscle strain injury due to excessive workload during training/competition.

Comparison of Muscle Regeneration Effects at Different Melittin Concentrations in Rabbit Atrophied Muscle.

This research aimed to explore the healing impacts of Melittin treatment on gastrocnemius muscle wasting caused by immobilization with a cast in rabbits. Twenty-four rabbits were randomly allocated to four groups. The procedures included different injections: 0.2 mL of normal saline to Group 1 (G1-NS); 4 μg/kg of Melittin to Group 2 (G2-4 μg/kg Melittin); 20 μg/kg of Melittin to Group 3 (G3-20 μg/kg Melittin); and 100 μg/kg of Melittin to Group 4 (G4-100 μg/kg Melittin). Ultrasound was used to guide the injections into the rabbits' atrophied calf muscles following two weeks of immobilization via casting. Clinical measurements, including the length of the calf, the compound muscle action potential (CMAP) of the tibial nerve, and the gastrocnemius muscle thickness, were assessed. Additionally, cross-sectional slices of gastrocnemius muscle fibers were examined, and immunohistochemistry and Western blot analyses were performed following two weeks of therapy. The mean regenerative changes, as indicated by clinical parameters, in Group 4 were significantly more pronounced than in the other groups (p < 0.05). Furthermore, the cross-sectional area of the gastrocnemius muscle fibers and immunohistochemical indicators in Group 4 exceeded those in the remaining groups (p < 0.05). Western blot analysis also showed a more significant presence of anti-inflammatory and angiogenic cytokines in Group 4 compared to the others (p < 0.05). Melittin therapy at a higher dosage can more efficiently activate regeneration in atrophied gastrocnemius muscle compared to lower doses of Melittin or normal saline.

The Contribution of Some Anthropometric Measurements and Pulmonary Volumes to The Digital achievement of the Sprint 400-meter Competition Among Elite Runners in Palestine

The study aimed to identify the contribution of some anthropometric measurements and pulmonary volumes to the digital achievement of the sprint 400-meter running distance among elite runners in Palestine. To achieve this, the study was conducted on a purposely-defined sample of (18) elite runners in Palestine, aged between (18-22) years. The researchers used the descriptive analytical method because it suits the nature of the study. Anthropometric measurements were conducted related to (age, body mass, height, arm length, leg length, thigh length, lower leg length, instep length, chest circumference, chest circumference with inspiration, abdominal circumference, thigh circumference, calf (Gastrocnemius) muscle circumference, upper arm circumference, and related Pulmonary volume measurements. Related Pulmonary volume measurements were taken (VC, FVC, FEV1, FWV1/FVC%, MVV, TV, RV, IC). After data was collected, it was processed statistically using Statistical Packages for Social Sciences (SPSS) software. The results of the study showed that the most contributing anthropometric measurements to the digital achievement of the sprint 400-meter running competition among elite runners in Palestine was the Thigh circumference, which explained (59.8%) of the achieved time. The study also found that the Pulmonary measurement that most contributed to the digital achievement of the sprint 400-meter running competition among elite runners in Palestine was the Vital Capacity (VC), as it was able to explain (61.6%) of the completion time.

Velocity-compensated intravoxel incoherent motion of the human calf muscle.

To determine whether intravoxel incoherent motion (IVIM) describes the blood perfusion in muscles better, assuming pseudo diffusion (Bihan Model 1) or ballistic motion (Bihan Model 2). IVIM parameters were measured in 18 healthy subjects with three different diffusion gradient time profiles (bipolar with two diffusion times and one with velocity compensation) and 17 b-values (0-600 s/mm2) at rest and after muscle activation. The diffusion coefficient, perfusion fraction, and pseudo-diffusion coefficient were estimated with a segmented fit in the gastrocnemius medialis (GM) and tibialis anterior (TA) muscles. Velocity-compensated gradients resulted in a decreased perfusion fraction (6.9% ± 1.4% vs. 4.4% ± 1.3% in the GM after activation) and pseudo-diffusion coefficient (0.069 ± 0.046 mm2/s vs. 0.014 ± 0.006 in the GM after activation) compared to the bipolar gradients with the longer diffusion encoding time. Increased diffusion coefficients, perfusion fractions, and pseudo-diffusion coefficients were observed in the GM after activation for all gradient profiles. However, the increase was significantly smaller for the velocity-compensated gradients. A diffusion time dependence was found for the pseudo-diffusion coefficient in the activated muscle. Velocity-compensated diffusion gradients significantly suppress the IVIM effect in the calf muscle, indicating that the ballistic limit is mostly reached, which is supported by the time dependence of the pseudo-diffusion coefficient.

Comparing the Effectiveness of Soft Tissue Manipulation and IASTM for Calf Muscle Tightness in Spastic Cerebral Palsy Children

This experimental study aimed to assess the effectiveness of soft tissue manipulation and Instrument Assisted Soft Tissue Mobilization (IASTM) in alleviating calf muscle tightness in children diagnosed with spastic cerebral palsy (CP). Cerebral palsy, a condition affecting two to three out of every 1,000 live births, encompasses a range of challenges related to movement, posture, gait abnormalities, and balance issues. Specifically, spastic diplegic cerebral palsy, characterized by leg spasticity, often results in walking difficulties, with tiptoeing as a common symptom due to calf muscle tightness. The study involved 30 children aged 5-12 diagnosed with spastic cerebral palsy at ACS Medical College and Hospital. Participants meeting the inclusion criteria were divided into two groups: Group receiving soft tissue manipulation and Group B undergoing IASTM. Outcome measures included goniometry and the Modified Ashworth Scale. Random sampling was employed to select subjects, with exclusions for specific medical conditions. Written consent was obtained and demographic data were collected. Based on goniometry and the Modified Ashworth Scale, both interventions demonstrated highly significant differences in mean values within their respective groups. The findings underscore the potential efficacy of both soft tissue manipulation and IASTM in addressing calf muscle tightness in children with spastic cerebral palsy.

Bigger calves from doing higher resistance training volume?

We compared the effects of different calf training weekly sets on muscle size changes. Sixty-one untrained young women performed a calf training program for 6 weeks, 3 d·wk-1, with differences in the resistance training volume. The participants were randomly assigned to 1 of the 3 groups: 6-SET, 9-SET, and 12-SET calf training weekly sets. The calf raise exercise was performed in sets of 15-20 repetitions maximum. The muscle thickness measurements of medial gastrocnemius (MG), lateral gastrocnemius (LG), and soleus (SOL) were taken via B-mode ultrasound. We used the sum of the three-muscle thickness as a proxy for the triceps surae (TSSUM). The 12-SET group elicited greater increases than 6-SET in LG (6-SET = +8.1% vs. 12-SET = +14.3%; P = 0.017), SOL (6-SET = +6.7% vs. 12-SET = +12.7%; P = 0.024), and TSSUM (6-SET = +6.9% vs. 12-SET = +12.0%; P = 0.005), but there was no significant difference in MG changes (6-SET = +6.6% vs. 12-SET = +9.9%; P = 0.067). There were no significant differences when comparing 9-SET vs. 6-SET and 12-SET (P ≥ 0.099). Although all groups experienced calf muscle hypertrophy, our results suggest that the higher dose range may optimize triceps surae muscle size gains.

Lactate and hydrogen ions play a predominant role in evoking the exercise pressor reflex during ischaemic contractions but not during freely perfused contractions.

We investigated the role played by lactate and hydrogen in evoking the exercise pressor reflex (EPR) in decerebrated rats whose hindlimb muscles were either freely perfused or ischaemic. Production of lactate and hydrogen by the contracting hindlimb muscles was manipulated by knocking out the myophosphorylase gene (pygm). In knockout rats (pygm-/-; n=13) or wild-type rats (pygm+/+; n=13), the EPR was evoked by isometrically contracting the triceps surae muscles. Blood pressure, tension, blood flow, renal sympathetic nerve activity and blood lactate concentrations were measured. Intramuscular metabolites and pH changes induced by the contractions were quantified by 31P-magnetic resonance spectroscopy (n=5). In a subset of pygm-/- rats (n=5), contractions were evoked with prior infusion of lactate (pH 6.0) in an attempt to restore the effect of lactate and hydrogen ions. Contraction of freely perfused muscles increased blood lactate and decreased muscle pH in pygm+/+ rats only. Despite these differences, the reflex pressor and sympathetic responses to freely perfused contraction did not differ between groups (P=0.992). During ischaemia, contraction increased muscle lactate and hydrogen ion production in pygm+/+ rats (P<0.0134), whereas it had no effect in pygm-/- rats (P>0.783). Likewise, ischaemia exaggerated the reflex pressor, and sympathetic responses to contraction in pygm+/+ but not in pygm-/- rats. This exaggeration was restored when a solution of lactate (pH 6.0) was infused prior to the contraction in pygm-/- rats. We conclude that lactate and hydrogen accumulation in contracting myocytes play a key role in evoking the metabolic component of the EPR during ischaemic but not during freely perfused contractions. KEY POINTS: Conflicting results exist about the role played by lactate and hydrogen ions in evoking the exercise pressor reflex. Using CRISP-Cas9, we rendered the myophosphorylase gene non-functional to block the production of lactate and hydrogen ions. The exercise pressor reflex was evoked in decerebrated rats by statically contracting the triceps surae muscles with or without muscle ischaemia. Static contraction elevated the concentration of lactate and hydrogen ions in pygm+/+ but not in pygm-/- rats. Despite these differences, the exercise pressor reflex was not different between groups. Acute muscle ischaemia exaggerated the concentration of lactate and hydrogen ions in pygm+/+ but not in pygm-/- rats. Likewise, acute muscle ischaemia exaggerated the exercise pressor reflex in pygm+/+ but not in pygm-/- rats. We conclude that lactate and hydrogen play a key role in evoking the exercise pressor reflex during ischaemic but not during freely perfused contractions.

CRIM-negative infantile Pompe disease, long-term observation of the effect of enzyme replacement therapy: a clinical case

Background. Infantile-onset form of Pompe disease (IOPD) comprises a progressive and fatal disease in the absence of pathogenetic treatment. Enzyme replacement therapy using biologically active recombinant human alglucosidase alfa is considered as a treatment option to increase the life expectancy of patients with early diagnosis and timely initiation of therapy.Case description. A child aged 5 months was delivered to the Cardiology Department of Children’s Republican Clinical Hospital (Tatarstan, Russia) for examination and clarification of the diagnosis. The patient’s parents complained of his shortness of breath, unproductive cough, cyanosis of the nasolabial triangle when restless, weakness, lethargy during breastfeeding session, as well as decreased appetite up to refusal to eat, constantly enlarged tongue. The examination revealed macroglossia and hypersalivation, pseudohypertrophy of calf muscles, dyspnea involving the accessory muscles, hepatomegaly, diffuse muscular hypotonia. Laboratory tests revealed an increase in alanine aminotransferase level greater than four times the normal values, aspartate aminotransferase level — more than nine times, a significant rise of creatine phosphokinase and lactate dehydrogenase, as well as natriuretic peptide. Echocardiography revealed significant myocardial hypertrophy of both the left and right ventricles. Complaints, medical history, clinical examination, and all of the above changes in laboratory and instrumental examinations suggested a group of hereditary metabolic diseases (Pompe disease), confirmed by a pronounced decrease in the activity of the alpha-glucosidase enzyme to 0.12 μmol/l/h in dry blood spots with subsequent molecular genetic study and detection of compound-heterozygous mutations in the GAA gene. It was decided to initiate specific enzyme replacement therapy by intravenous administration of a recombinant form of human acidic alpha-glucosidase (alglucosidase alfa) at a dose of 20 mg/kg/injection in a frequency of once every 2 weeks. In addition, CRIM (cross-reactive immunological material)-negative status determined immune tolerance therapy, including the most studied combination of three drugs: rituximab, methotrexate, and intravenous immunoglobulin, as a response to enzyme replacement therapy. Long-term observation of the effect of enzyme replacement therapy brought positive results in the form of new motor skills, decreased content of intracellular enzymes and natriuretic peptide, reduction of myocardial hypertrophy of the left and right ventricles. In the future, the child needs lifelong treatment.Conclusion. Awareness of physicians about Pompe disease will prevent the growth in diagnostic errors and neglected cases. In case of early confirmation, the effectiveness of currently available ERT increases: the possibility to stop the disease progression, to reverse its individual clinical manifestations, and to improve the patient’s quality of life.

Evidence of different sensitivity of muscle and tendon to mechano-metabolic stimuli.

This study aimed to examine the temporal dynamics of muscle-tendon adaptation and whether differences between their sensitivity to mechano-metabolic stimuli would lead to non-uniform changes within the triceps surae (TS) muscle-tendon unit (MTU). Twelve young adults completed a 12-week training intervention of unilateral isometric cyclic plantarflexion contractions at 80% of maximal voluntary contraction until failure to induce a high TS activity and hence metabolic stress. Each participant trained one limb at a short (plantarflexed position, 115°: PF) and the other at a long (dorsiflexed position, 85°: DF) MTU length to vary the mechanical load. MTU mechanical, morphological, and material properties were assessed biweekly via simultaneous ultrasonography-dynamometry and magnetic resonance imaging. Our hypothesis that tendon would be more sensitive to the operating magnitude of tendon strain but less to metabolic stress exercise was confirmed as tendon stiffness, Young's modulus, and tendon size were only increased in the DF condition following the intervention. The PF leg demonstrated a continuous increment in maximal AT strain (i.e., higher mechanical demand) over time along with lack of adaptation in its biomechanical properties. The premise that skeletal muscle adapts at a higher rate than tendon and does not require high mechanical load to hypertrophy or increase its force potential during exercise was verified as the adaptive changes in morphological and mechanical properties of the muscle did not differ between DF and PF. Such differences in muscle-tendon sensitivity to mechano-metabolic stimuli may temporarily increase MTU imbalances that could have implications for the risk of tendon overuse injury.

Nonlinear dynamics of postural control system under visual-vestibular habituation balance practice: evidence from EEG, EMG and center of pressure signals.

Human postural control system is inherently complex with nonlinear interaction among multiple subsystems. Accordingly, such postural control system has the flexibility in adaptation to complex environments. Previous studies applied complexity-based methods to analyze center of pressure (COP) to explore nonlinear dynamics of postural sway under changing environments, but direct evidence from central nervous system or muscular system is limited in the existing literature. Therefore, we assessed the fractal dimension of COP, surface electromyographic (sEMG) and electroencephalogram (EEG) signals under visual-vestibular habituation balance practice. We combined a rotating platform and a virtual reality headset to present visual-vestibular congruent or incongruent conditions. We asked participants to undergo repeated exposure to either congruent (n = 14) or incongruent condition (n = 13) five times while maintaining balance. We found repeated practice under both congruent and incongruent conditions increased the complexity of high-frequency (0.5-20 Hz) component of COP data and the complexity of sEMG data from tibialis anterior muscle. In contrast, repeated practice under conflicts decreased the complexity of low-frequency (<0.5 Hz) component of COP data and the complexity of EEG data of parietal and occipital lobes, while repeated practice under congruent environment decreased the complexity of EEG data of parietal and temporal lobes. These results suggested nonlinear dynamics of cortical activity differed after balance practice under congruent and incongruent environments. Also, we found a positive correlation (1) between the complexity of high-frequency component of COP and the complexity of sEMG signals from calf muscles, and (2) between the complexity of low-frequency component of COP and the complexity of EEG signals. These results suggested the low- or high-component of COP might be related to central or muscular adjustment of postural control, respectively.

P101 Investigating the association between clinical enthesitis and central sensitisation in psoriatic arthritis

Abstract Background/Aims Psoriatic Arthritis (PsA) is an inflammatory arthritis with enthesitis as its characteristic clinical feature. Enthesitis can be clinically challenging to differentiate from the widespread pain associated with Fibromyalgia (FM), the prototype of central sensitisation (CS) present in up to 30% of PsA patients. Algometry is used in CS research to quantify pressure pain threshold (PPT), reflecting increased pain sensitivity when reduced. Ultrasound is a valuable tool to evidence entheseal inflammatory changes in PsA. This study investigates associations between CS, i.e., FM, and entheseal ultrasound outcomes to better characterise pain mechanisms in PsA enthesitis. Methods A total of 20 patients with active PsA about to start a new immunosuppressant were recruited. Ultrasound evaluation of non-dominant knee (left for all patients) using dynamic B-mode and power Doppler was performed alongside the Leeds Enthesitis Index (LEI) collection to assess enthesitis. PPT was measured with algometry at the non-dominant knee (enthesitis), trapezius and calf muscle (CS areas), and collection of the ACR 2011 FM criteria was used to determine the presence of CS. Non-dominant areas were selected because they are less likely to exhibit biomechanical ultrasound alterations; moreover, the non-dominant side is generally more sensitive than the dominant side, thus enabling more precise PPT measurements. Correlations and t-tests were used to test associations between variables collected. SPSS was used to analyse the data. Results The 30% of patients met the FM criteria and presented higher LEI scores and lower PPT evoked threshold than FM-negative patients. Total FM scores significantly correlated with LEI scores (r = 0.69, p &amp;lt; 0.001) and calf PPTs (r=-0.53, p=-0.014), but not with knee and trapezius PPTs (r=-0.49, p = 0.09; r=-0.30, p = 0.19), or US enthesitis (r=-0.04, p = 0.86). PPTs in the areas investigated did not show significant correlations with US enthesitis, while an indirect association was observed between LEI with calf PPT (r=-0.51, p = 0.02) and trapezius PPT (r=-0.41, p = 0.06). No significant correlation was demonstrated between LEI and left knee enthesitis (r=-0.32, p = 0.17). Conclusion FM is frequent in PsA and can mimic entheseal pain, as suggested by the strong correlation with the LEI scores. In our cohort, LEI scores did not efficiently capture inflammatory enthesitis, demonstrated by the lack of association with ultrasound data. Moreover, the association between objective measurement of CS, including calf and trapezius PPTs, supports that LEI score may primarily reflect the presence of central sensitisation rather than inflammation. Therefore, relying solely on clinical detection of enthesitis may result in inappropriate treatment escalation. Ultrasound, conversely, serves as a dependable tool for confirming enthesitis and providing valuable information for making informed treatment decisions. Disclosure N.M. Aldehmi: None. N. Basu: None. J. Dale: None. A. Najm: None. F. Sunzini: None.

Société de Biomécanique young investigator award 2022: Effects of applying functional electrical stimulation to ankle plantarflexor muscles on forward propulsion during walking in young healthy adults

The triceps surae muscle, composed of the gastrocnemius and soleus muscles, plays a major role in forward propulsion during walking. By generating positive ankle power during the push-off phase, these muscles produce the propulsive force required for forward progression. This study aimed to test the hypothesis that applying functional electrical stimulation (FES) to these muscles (soleus, gastrocnemius or the combination of the two) during the push-off phase would increase the ankle power generation and, consequently, enhance forward propulsion during walking in able-bodied adults. Fifteen young adults walked at their self-selected speed under four conditions: no stimulation, with bilateral stimulation of the soleus, gastrocnemius, and both muscles simultaneously. Muscles were stimulated just below the discomfort threshold during push-off, i.e., from heel-off to toe-off. FES significantly increased ankle power (+22 to 28 % depending on conditions), propulsive force (+15 to 18 %) and forward progression parameters such as walking speed (+14 to 20 %). Furthermore, walking speed was significantly higher (+5%) for combined soleus and gastrocnemius stimulation compared with gastrocnemius stimulation alone, with no further effect on other gait parameters. In conclusion, our results demonstrate that applying FES to the gastrocnemius and soleus, separately or simultaneously during the push-off phase, enhanced ankle power generation and, consequently, forward propulsion during walking in able-bodied adults. Combined stimulation of the soleus and gastrocnemius provided the greatest walking speed enhancement, without affecting other propulsion parameters. These findings could be useful for designing FES-based solutions for improving gait in healthy people with propulsion impairment, such as the elderly.

Extranodal natural killer/T cell lymphoma of the skeletal muscle.

This case report highlights a case of extranodal NK/T cell lymphoma initially misdiagnosed as myositis, emphasizing the appearance on both MRI and FDG PET images. The patient presented with systemic symptoms and calf muscle swelling, prompting imaging studies that revealed diffuse muscle involvement. Despite negative myositis markers and inconclusive biopsy, post-amputation findings confirmed lymphoma with EBV positivity. The appearance in both MRI and FDG PET complicated the diagnostic process, underscoring the importance of considering lymphoma in cases of muscle-related symptoms to prevent delays in appropriate management. This case contributes to the understanding of the diagnostic challenges associated with extranodal NK/T cell lymphoma and emphasizes the significance of peripheral band-like features in imaging studies.

Is Kinesio taping acutely effective for peripheral tissue perfusion in women with mild to moderate chronic venous insufficiency? A randomized controlled trial

Objective To evaluate the acute effect of Kinesio Taping® (KT) on peripheral tissue perfusion in women with chronic venous insufficiency (CVI). Methods: This randomized, double-blind controlled trial included 59 women with mild to moderate CVI. They were randomized to a control group (n = 23; 54.08 ± 9.04 years) and KT group (n = 36; 55.87 ± 9.97 years). Near-infrared spectroscopy was positioned in the medial gastrocnemius muscle for assessment of resting tissue perfusion 48 h after the first day of evaluation and after placement of the Kinesio Taping® tape. The evaluation also consisted of performing movements of the plethysmography examination. To verify the comparisons of pre- and post-Kinesio Taping® data, the variation delta was used for analysis. Mann–Whitney U test was performed an an alpha of 5% was considered statistically significant. Results: There wasn't a significant difference between groups regarding the peripheral tissue perfusion evaluation variables Peripheral Oxygen Saturation Difference – DELTA_SPO2: (KT Group 3.21 (0.84–3.62); Control 2.21 (1.59–4.83), p = 0.219) and Difference in deoxygenate hemoglobin values – DELTA_HHB (units) KT Group -0.62 (-2.14–0.67); Control Group -0.07 (-2.15–2.62) p = 0.238). Despite the lack of statistical significance, the KT group had a 785.7% greater drop in HHB values than the control group. Conclusions: Acute use of Kinesio Taping® in women with CVI did not significantly alter tissue perfusion of calf muscles. However, it was possible to observe percentage differences in venous retention to be considered from a clinical point of view

Are Diminishing Potentiation and Large Extensor Moments the Cause for the Occurrence of the Sticking Region in Maximum Free-Weight Barbell Back Squats among Resistance-Trained Males?

This study compared the kinematics, surface electromyography (sEMG) and kinetics among isometric squats performed at 10 different heights of the upward part and a one-repetition maximum (1-RM) squat. Eleven males (age: 27.5 ± 3.4 years, body mass: 84.9 ± 8.1 kg, body height: 1.79 ± 0.06 m, 1-RM squat: 152.2 ± 20.55 kg) took part in this study. It was found that force output was lowest in the sticking region at around the event of peak deceleration for the 1-RM trial with force output at 2179 ± 212 N. For the isometric trial, the lowest force output occurred at the lowest barbell height (1735 ± 299 N). In addition, for the 1-RM condition hip extension moments peaked at the first four barbell heights (6.5-6.2 Nm/kg) representing the pre-sticking and the sticking region before significantly decreasing during the events representing the post-sticking region. Additionally, the sEMG amplitude peaked for the hip extensors at the barbell heights corresponding to the post-sticking region. Moreover, the sEMG amplitude was significantly higher for the 1-RM condition for all hip extensors, vastus lateralis, and calf muscles (F ≥ 2.7, p ≤ 0.01, ηp2 ≥ 0.25). Therefore, we suggest that the sticking region occurs because of reduced force output in the pre-sticking and the sticking region in back squats among resistance-trained males. The reduced force output is probably a combination of suboptimal internal moment arms, length-tension relationships of the gluteus maximus, hamstring and vastii muscles in the pre-sticking and sticking regions to overcome the large extensor moments together with diminishing potentiation from the pre-sticking to the sticking region.

Triceps surae shortening in children

BACKGROUND: The triceps surae is the main muscle that exerts propulsion power during walking and running. Its retraction changes the biomechanics of the foot, alters locomotion, and results in the secondary development of flatfoot deformity. Literature data on the clinical assessment of triceps surae retraction vary.&#x0D; AIM: To assess the threshold value of foot dorsiflexion in different clinical assessment methods of determining Achilles tendon shortening.&#x0D; MATERIALS AND METHODS: The study included the clinical assessment results of foot dorsiflexion in 167 patients (325 feet) with flatfeet aged 7–18 years. The foot dorsiflexion evaluation consisted of the assessment of isolated foot dorsiflexion and foot dorsiflexion with stabilization of the tarsal joints. To determine the involvement of the gastrosoleus complex in the pathological process, foot dorsiflexion was assessed with knee joint flexion and extension. The obtained data were subjected to correlation, regression, and Bland–Altman analyses.&#x0D; RESULTS: Strong correlations were found when foot dorsiflexion was assessed with the same knee joint position (assessment of isolated foot dorsiflexion and foot dorsiflexion with stabilized tarsal joints and knee joint flexion; the same tests with knee joint extension). Moderate correlations were noted when comparing foot dorsiflexion with knee joint extension and flexion. In the regression analysis, formulas were obtained according to which the threshold values of foot dorsiflexion were calculated in various variants during knee joint flexion and extension, indicating the retraction of the triceps surae: isolated foot dorsiflexion with knee joint extension 20°, isolated foot dorsiflexion with knee flexion 36°, and foot dorsiflexion with tarsal joint stabilization and knee extension 23°.&#x0D; CONCLUSIONS: Retraction of triceps surae in children with flatfeet equally involves the gastrocnemius and soleus. Differences in the magnitude of foot dorsiflexion with knee joint flexion and extension are the main factors in the retraction of the triceps surae to the gastrocnemius muscle.

Aortic Angiosarcoma Manifesting as Multiple Musculoskeletal Metastases: A Case Report.

Aortic angiosarcomas are rare. Due to its rarity and metastatic presentation, it is difficult to diagnose metastatic aortic angiosarcoma. We describe the clinicopathological and radiologic features of a metastatic aortic angiosarcoma presenting as musculoskeletal metastases. A 59-year-old male patient presented with left thigh pain. Plain radiographs revealed multifocal osteolytic lesions in the left femur shaft. Abdominopelvic computed tomography showed a lobulated osteolytic lesion in the left iliac bone. Magnetic resonance images revealed multifocal soft tissue lesions in the thigh musculature. A positron emission tomography/computed tomography (PET/CT) scan demonstrated multiple foci of increased uptake in the left femur bone, pelvis, left thigh, and calf musculature. Focal increased uptake in the lower abdominal aorta was newly detected. Pelvis biopsy showed tumor cell nests of epithelioid cells. The tumor cells showed vasoformative features. Immunohistochemically, the tumor cells showed positivity for vimentin, CD31, and ERG. The pathologic diagnosis of epithelioid angiosarcoma was established. The origin of the tumor was presumed to be the aorta. This case underscores the importance of PET scans in identifying primary lesions. In terms of the histopathologic diagnosis of biopsy samples with tumor cells exhibiting epithelioid neoplastic morphology, employing appropriate ancillary techniques such as immunocytochemistry with vascular markers may assist in accurately diagnosing metastatic angiosarcoma.