Entire Muscle Research Articles

Intra-session and inter-rater reliability of spatial frequency analysis methods in skeletal muscle.

Spatial frequency analysis (SFA) is a quantitative ultrasound (US) method originally developed to assess intratendinous tissue structure. This method may also be advantageous in assessing other musculoskeletal tissues. Although SFA has been shown to be a reliable assessment strategy in tendon tissue, its reliability in muscle has not been investigated. The purpose of this study was to examine the reliability of spatial frequency parameter measurement for a large muscle group within a healthy population. Ten participants with no history of lower extremity surgery or hamstring strain injury volunteered. Longitudinal B-mode images were collected in three different locations across the hamstring muscles. Following a short rest, the entire imaging procedure was repeated. B-mode images were processed by manually drawing a region of interest (ROI) about the entire muscle thickness. Four spatial frequency parameters of interest were extracted from the image ROIs. Intra- and inter-rater reliabilities of extracted SFA parameters were performed. Test-retest reliability of the image acquisition procedure was assessed between repeat trials. Intraclass correlation coefficients showed high intra- and inter-rater reliability (ICC(3,1) > 0.9 for all parameters) and good to moderate test-retest reliability (ICC(3,1) > 0.50) between trials. No differences in parameter values were observed between trials across all muscles and locations (p > 0.05). The high reliability metrics suggest that SFA will be useful for future studies assessing muscle tissue structure, and may have value in assessing muscular adaptations following injury and during recovery.

Complete Adipose Replacement of Bilateral Medial Gastrocnemius Muscle - A Cadaveric Case Report

Sarcopenia and infiltration of intermuscular adipose tissue are often seen in older adults due to aging process, but a muscle is completely replaced by adipose tissue is rarely reported. In this cadaveric case, we describe an observation of bilateral symmetric adipose replacement of the medial gastrocnemius muscles (GM) on both left and right leg in an 82-year old Caucasian female, whose cause of death was advanced dementia. The white adipose tissue replaced the entire medial GM muscle belly with pennate-like arrangement, indicating adipose tissue infiltration very likely into the original muscle cells. Where and how these adipose tissues come from are discussed.

Human Medial Gastrocnemius Conversion To Adipose Tissue, A Histological Analysis

There are very rare reports in the biomedical literature of entire human skeletal muscles being replaced by adipose tissue and thereby affecting lower limb function and ambulation. The causes are unknown. A fully preserved example was discovered in a Medical Anatomy course. PURPOSE: To examine the histological characteristics of a bilateral conversion of the medial gastrocnemii, presumably from skeletal muscle to adipose tissue. METHODS: Small specimens were collected for preservation, wax embedding, and histological analysis of the affected muscle, unaffected lateral-head of the muscle, nerve, and a control muscle. RESULTS: Hematoxylin and Eosin staining revealed an 88% decrease in the number of skeletal muscle fibers with a corresponding increase in the number of adipocytes. Connective tissue was similar between samples; however, the lateral gastrocnemius exhibited signs of inflammation with no necrosis. CONCLUSIONS: This is to our knowledge the first full histological analysis of a seeming conversion of the bilateral gastrocnemius medial heads into adipose tissue. The cause is unknown but could be related to the immune cell infiltration.

Whole-Body Imaging of Neural and Muscle Activity during Behavior in Hydra vulgaris: Effect of Osmolarity on Contraction Bursts.

The neural code relates the activity of the nervous system to the activity of the muscles to the generation of behavior. To decipher it, it would be ideal to comprehensively measure the activity of the entire nervous system and musculature in a behaving animal. As a step in this direction, we used the cnidarian Hydra vulgaris to explore how physiological and environmental conditions alter simple contractile behavior and its accompanying neural and muscle activity. We used whole-body calcium imaging of neurons and muscle cells and studied the effect of temperature, media osmolarity, nutritional state, and body size on contractile behavior. In mounted Hydra preparations, changes in temperature, nutrition state, or body size did not have a major effect on neural or muscle activity, or on contractile behavior. But changes in media osmolarity systematically altered contractile behavior and foot detachments, increasing their frequency in hypo-osmolar media solutions and decreasing it in hyperosmolar media. Similar effects were seen in ectodermal, but not in endodermal muscle. Osmolarity also bidirectionally changed the activity of contraction burst (CB) neurons, but did not affect the network of rhythmic potential (RP) neurons in the ectoderm. These findings show osmolarity-dependent changes in the activity of CB neurons and ectodermal muscle, consistent with the hypothesis that CB neurons respond to media hypo-osmolarity, activating ectodermal muscle to generate CBs. This dedicated reflex could serve as an excretory system to prevent osmotic injury. This work demonstrates the feasibility of studying an entire neuronal and muscle activity in a behaving animal.

Blunt Transection of the Entire Anterolateral Abdominal Wall Musculature Following Seatbelt-Related Injury

Traumatic abdominal wall hernias (TAWHs) are uncommon and the incidence of this, which is rarely encountered in clinical practice, has been estimated at 1%. Furthermore, blunt transection of the entire abdominal wall musculature caused by seatbelt is a very rare complication. We report a case of adult with a complete disruption of the entire anterolateral abdominal wall muscle following the seatbelt injury. A 32-year-old male was wearing a seat belt in a high speed motor vehicle collision. Abdominal computed tomography (CT) scan revealed the complete disruption of bilateral abdominal wall musculatures including TAWH without visceral injury. However, injuries of small bowel and sigmoid colon were observed in the intra-operative field. The patient underwent the repair by primary closure of the defect with absorbable monofilament sutures. This case suggests that especially in TAWH patients, even if a CT scan is normal, clinicians should keep the possibility of bowel injury in mind, and choose a treatment based on the clinical findings. Keywords: Hernia, Abdominal; Seat belts; Abdominal muscles; Herniorrhaphy; Multiple trauma

Ultrasound method of the USVALID study to measure subcutaneous adipose tissue and muscle thickness on the thigh and upper arm: An illustrated step-by-step guide

Summary Objective So far there is no standardised widely accepted ultrasound method for assessment of both subcutaneous adipose tissue and muscle mass in healthy subjects, patients and ICU patients. The goal is to provide an illustrated step-by-step guide of the ultrasound method developed since 2011, refined and applied during the USVALID study. Methods We use 2 linear probes with a footprint width of 25,6 and 38,4 mm. The subject is lying relaxed with the head of bed elevated to 30°. Foam supports are placed under elbows and knees. Precise anatomical landmarks are palpated to measure the limb lengths. 3 measuring points at 50% of the thigh length and 2 measuring points at 70% of the upper arm length are marked on both sides. A gelpad is used to enable minimal compression. It is verified that the borders of the scan are blurred. Each measuring point is scanned in the short-axis and long-axis plane to more easily determine the subcutaneous adipose tissue and muscle structures especially in the presence of edema. First the quality of the scan is evaluated according to the visibility of the muscle fascia and bone surface. Then subcutaneous adipose tissue and entire muscle thickness are measured at the exact center of the scan drawing the shortest possible line from skin to bone surface. Discussion The illustrated description of the USVALID ultrasound method enables reproducibility by other researchers for external validity. The subject's position, the location of the measuring points, the performance and evaluation of the ultrasound scans are discussed and compared to other published ultrasound methodologies.

Electromyographic activity of the vastus medialis and gastrocnemius implicates a slow stretch-shortening cycle during rowing in the field

The consideration of the temporal and electromyographic (EMG) characteristics of stretch-shortening cycles (SSC) are crucial for the conceptualization of discipline-specific testing and training. Since leg muscles are first stretched (eccentric) and then contracted (concentric) during rowing, it can be assumed that the entire muscle tendon complex performs a SSC. Thus, it should be elucidated whether the rowing cycle can be attributed to either a slow or fast SSC. Therefore, EMG of the vastus medialis and gastrocnemius were captured (n = 10, 22.8 ± 3.1 years, 190 ± 6 cm, 82.1 ± 9.8 kg) during (single scull) rowing and subsequently compared to typical slow (countermovement jump, CMJ) and fast (drop jump, DJ) SSCs. The elapsed time between the EMG onset and the start of the eccentric phase was monitored. The pre-activation phase (PRE, before the start of the eccentric phase) and the reflex-induced activation phase (RIA 30–120 ms after the start of the eccentric phase) have been classified. Notable muscular activity was observed during DJ before the start of the eccentric phase (PRE) as well as during RIA. In contrast, neither CMJ nor rowing revealed any EMG-activity in these two phases. Interestingly, CMJ and race-specific rowing showed an EMG-onset during the eccentric phase. We conclude that rowing is more attributable to a slow SSC and implies that fast SSC does not reflect discipline specific muscle action and could hamper rowing-performance-enhancement.

Microsurgical anatomy of the stapedius muscle in adult cadavers.

This study aimed to establish an extended morphometric dataset regarding the stapedius muscle for anatomists and otologists. The tympanic cavity of ten cadavers (five females, five males) aged with 75.70 ± 13.75years was bilaterally dissected. Morphometric properties of the stapedius muscle (i.e., its muscular belly and tendon) and its relationship with the neighborhood structures including the facial nerve was evaluated. The length of the entire stapedius muscle was found as 4.80 ± 1.13mm. The depth between the entrance of the external auditory canal and stapedius muscle was measured as 18.23 ± 2.30mm. The incudostapedial joint and stapedial tendon were found to be 1.66 ± 0.25mm and 1.18 ± 0.19mm away from the facial nerve, respectively. The stapedial tendon length was standardized as five types: Type 1, extremely short tendon (under 0.5mm), 5% of cases; Type 2, short tendon (between 0.5 and 1mm), 30% of cases; Type 3, normal tendon (between 1 and 2mm), 55% of cases; Type 4, long tendon (between 2 and 2.5mm), 10% of cases; and Type 5, extremely long tendon (above 2.5mm), no cases. Our findings showed that the stapedius tendon size in adults was quite similar to fetuses. Therefore, probably entire muscle dimension does not alter after birth. Considering the concordance between direct anatomic (our findings) and radiologic measurements (literature findings) of the stapedius muscle, preoperative radiological evaluation may be important for otologists in terms of the choice of surgical tools such as diamond burr sizes. Due to the lack of standardization regarding the evaluation of the stapedius tendon size (i.e., extremely short or extremely long), we defined the tendons below 0.5mm as extremely short (Type 1) and above 2.5mm as extremely long (Type 5).

Short Communication: Investigating woody breast disease and broiler chicken activity using an automated tracking software program

ABSTRACT Objective This research quantified the effect of woody breast disease (WBD) presence and severity on activity in broilers. Materials and Methods Broiler cockerel chicks (n = 27) were enrolled over 2 periods and individually housed. Video data were collected continuously from 21 to 55 d of age. Behavior was analyzed over a 4-h interval using EthoVision XT automated tracking software to quantify total activity. Birds were slaughtered at 55 d of age and assigned a woody breast severity score (0–2) based on manual palpation and visual observation. Results and Discussion Of the 25 birds that survived for the duration of the study, 6 birds were assigned a severity score of 0 (no evidence of WBD), 14 a severity score of 1 (firm focal lesions), and 5 a severity score of 2 (diffuse firmness of the entire pectoralis major muscle). Neither WBD presence nor severity had an effect on total activity (P > 0.05). In the present study, no effect of WBD on activity was detected using an automated tracking software program for behavior quantification. However, limitations of the software and the potential presence of microscopic lesions in birds with a severity score of 0 may be contributing to this outcome. Implications and Applications Although WBD has significant financial implications for the poultry industry, limited research has evaluated the effect of WBD on bird welfare and behavior. Future studies should measure a more diverse set of behaviors while also analyzing muscle histology to better elucidate any associations between WBD and behavior.

Interdisciplinary Approach to the Temporomandibular Joint Osteoarthritis-Review of the Literature.

Background and objectives: There is an increasing number of patients applying for dental treatment who suffer from temporomandibular joint osteoarthritis (TMJOA). Osteoarthritis may be the cause of the pain in the area of temporomandibular joints, but its course may also be absolutely asymptomatic. The aim of this study was to present an interdisciplinary approach to TMJOA, including current diagnostics and treatment modalities on the basis of the available literature. Materials and Methods: PubMed and Scopus databases were analyzed using the keywords: ((temporomandibular joint AND osteoarthritis) AND imaging) and ((temporomandibular joint AND osteoarthritis) AND treatment). The bibliography was supplemented with books related to the temporomandibular joint. After screening 2450 results, the work was based in total on 98 publications. Results and Conclusions: Osteoarthritis is an inflammatory, age-related, chronic and progressive degenerative joint disease. Magnetic resonance imaging (MRI) and cone-beam computed tomography (CBCT), together with clinical symptoms, play significant roles in TMJOA diagnosis. Current MRI techniques seem to be clinically useful for assessment of bony changes in temporomandibular joint (TMJ) disorders. Treatment of TMJOA requires a complex, interdisciplinary approach. TMJOA treatment includes the cooperation of physiotherapists, rheumatologists, gnathologists, orthodontists and quite often also maxillofacial surgeons and prosthodontists. Sometimes additional pharmacotherapy is indicated. Thorough examination of TMJ function and morphology is necessary at the beginning of any orthodontic or dental treatment. Undiagnosed TMJ dysfunction may cause further problems with the entire masticatory system, including joints, muscles and teeth.

Foci of Segmentally Contracted Sarcomeres in Trapezius Muscle Biopsy Specimens in Myalgic and Nonmyalgic Human Subjects: Preliminary Results.

The myofascial trigger point hypothesis postulates that there are small foci of contracted sarcomeres in resting skeletal muscle. Only one example, in canine muscle, has been published previously. This study evaluated human muscle biopsies for foci of contracted sarcomeres. The Departments of Rehabilitation Sciences and Physiotherapy at Ghent University, Ghent, Belgium. Biopsies from 28 women with or without trapezius myalgia were evaluated, 14 in each group. Muscle biopsies were obtained from regions of taut bands in the trapezius muscle and processed for light and electron microscopy and for histochemical analysis. Examination of the biopsies was blinded as to group. A small number of foci of segmentally contracted sarcomeres were identified. One fusiform segmental locus involved the entire muscle fiber in tissue from a myalgic subject. Several transition zones from normal to contracted sarcomeres were found in both myalgic and nonmyalgic subjects. The distance between Z-lines in contracted sarcomeres was about 25-45% of the same distance in normal sarcomeres. Z-lines were disrupted and smeared in the contracted sarcomeres. A small number of foci of segmentally contracted sarcomeres were found in relaxed trapezius muscle in human subjects, a confirmation of the only other example of spontaneous segmental contraction of sarcomeres (in a canine muscle specimen), consistent with the hypothesis of trigger point formation and with the presence of trigger point end plate noise.

A multiple fascicle muscle force model of the human triceps surae

Muscle is typically modelled using a lump sum idealization, scaling a single fascicle to represent the entire muscle. However, fascicles within a muscle have unique orientations, which could result in forces exerted not only in the axis running along the tendon, but also the two perpendicular axes, describing the muscle's width and depth. The purpose of this research was to develop a geometric-based model of the soleus, medial gastrocnemius, and lateral gastrocnemius as distributed force systems which can predict three-dimensional forces. Measurements were taken from the triceps surae in two human cadavers (80 and 85 years old). These models predicted muscle volumes and ankle plantar flexor moments that were realistic considering the age of the cadavers. Small differences were observed in calcaneal tendon force and moment for the distributed force models compared to modelling muscle force using a lump sum idealization. The major finding of the distributed force models was that forces were present in the axes corresponding to the muscle's length, width, and depth. The forces in the width and depth axes may be relevant for evaluating how muscle shape changes during contraction, as well as to investigate stress-strain patterns along the muscle's proximal and distal aponeuroses.

Sensory cilia as the Achilles heel of nematodes when attacked by carnivorous mushrooms

Fungal predatory behavior on nematodes has evolved independently in all major fungal lineages. The basidiomycete oyster mushroom Pleurotus ostreatus is a carnivorous fungus that preys on nematodes to supplement its nitrogen intake under nutrient-limiting conditions. Its hyphae can paralyze nematodes within a few minutes of contact, but the mechanism had remained unclear. We demonstrate that the predator-prey relationship is highly conserved between multiple Pleurotus species and a diversity of nematodes. To further investigate the cellular and molecular mechanisms underlying rapid nematode paralysis, we conducted genetic screens in Caenorhabditis elegans and isolated mutants that became resistant to P. ostreatus We found that paralysis-resistant mutants all harbored loss-of-function mutations in genes required for ciliogenesis, demonstrating that the fungus induced paralysis via the cilia of nematode sensory neurons. Furthermore, we observed that P. ostreatus caused excess calcium influx and hypercontraction of the head and pharyngeal muscle cells, ultimately resulting in rapid necrosis of the entire nervous system and muscle cells throughout the entire organism. This cilia-dependent predatory mechanism is evolutionarily conserved in Pristionchus pacificus, a nematode species estimated to have diverged from C. elegans 280 to 430 million y ago. Thus, P. ostreatus exploits a nematode-killing mechanism that is distinct from widely used anthelmintic drugs such as ivermectin, levamisole, and aldicarb, representing a potential route for targeting parasitic nematodes in plants, animals, and humans.

Action of galvanic current on an experimentally generated muscle lesion: preliminary findings

Abstract Background Recently, Abat et al evaluated the effect of the application of galvanic currents on a model of muscle injury in the rat by injection of intramuscular Notexin. In mice, Notexin causes a lesion of the entire muscle when in humans, complete affectation is exceptional. In this study, we evaluated the action of the galvanic current on muscle regeneration in partially lesioned muscles with bupivacaine. Aim To evaluate the action of the galvanic current in an animal model with partial muscle lesion generated with Bupivacaine. Material and Methods The experiments were performed in adult male Swiss mice who were intramuscularly inoculated with Bupivacaine (BPV) in the posterior muscle bundle of the leg. The control subjects were inoculated with physiological saline (PS). The galvanic current protocol used in this study was 1.5mA during 5 seconds and 3 applications (1.5:5:3; Physio Invasiva®, Grupo Prim). The electromyographic recording was performed at 72 hours and at 7 and 10 days, after the first administration (Medelec Synergy Ultrasound machine, concentric recording needle). The number of areas presenting endplate noise were evaluated and the frequency of endplate noise for each of these areas. Results Considering that the fibers which have been lesioned by bupivacaine are electromyographically silent, a registration of endplate noise was related with muscle regeneration. The number of areas with endplate noise considerably increased in the injured limb which received the galvanic current compared to the limb that was only lesioned in the first 72 hours. After this, there was no other modification in the number of areas. The frequency of the endplate noise of each area has been significantly greater in all the periods studied, indicating that galvanic current has facilitated muscle regeneration. It is worth noting that these are preliminary results and other more direct tests are pending. Conclusions The functional findings uncovered in this study, enable us to establish that the application of galvanic currents in an animal model of muscle injury reduce the recovery time of the damaged muscle tissue.

Muscle fat content in the intact infraspinatus muscle correlates with age and BMI, but not critical shoulder angle

Muscle fat content of the rotator cuff increases after a tear. In the healthy rotator cuff, the influence of age, body mass index (BMI) and critical shoulder angle (CSA) on muscle fat content is unknown. The primary aim was to correlate muscle fat content with age, BMI and CSA. The secondary aims were (1) to correlate muscle fat content in the entire muscle and slice Y (most lateral sagittal slice with scapular spine) and (2) assessed the reliability for CSA measurement in MRI. In 26 healthy shoulders (17 subjects), aged 40-65years, BMI 20-35kg/m2, Goutallier grade 0, Dixon MRI was applied. The CSA was > 35° in 14 shoulders and < 30° in 12 shoulders. Muscle fat content was calculated from Dixon MRI. Infraspinatus muscle fat content correlates moderately with age (r = 0.553; p = 0.003) and BMI (r = 0.517; p = 0.007). Supraspinatus muscle fat content does not correlate with age (r = 0.363, p = 0.069) and BMI (r = 0.342, p = 0.087). No correlation between CSA and muscle fat content was found. Muscle fat content measurementin the entire musclecorrelates strongly with measurement in slice Y (intraclass correlation coefficient supraspinatus muscle: 0.757; infraspinatus muscle: 0.794). CSA intermethod analysis between radiography and MR images shows very high reliability (intraclass correlation coefficient > 0.9) and no systematical deviation in Bland-Altman analysis. Muscle fat content in the healthy infraspinatus muscle does correlate with age and BMI, but not with the CSA. Muscle fat content measurement in the rotator cuff using Dixon MRI showed a high reliability between slice Y and the entire muscle. III.

Impact of Rectus Muscle Injury during Perforator Dissection on Functional Donor Morbidity after Deep Inferior Epigastric Perforator Flap Breast Reconstruction.

Background:This study aimed to assess the extent of rectus muscle damage in deep inferior epigastric perforator (DIEP) flap harvest and to evaluate its association with functional donor morbidity.Methods:A prospective cohort of 76 patients who underwent DIEP flap breast reconstruction was evaluated preoperatively and followed up for 1 year. Abdominal wall strength was assessed using the upper and lower rectus abdominis manual muscle function tests. Functional weakness was defined as a postoperative decrease in function by at least 2 scores. The effects of patient- and operation-related characteristics on adverse outcomes were also assessed.Results:The mean width of the transected rectus muscle was 2.2 cm (partial thickness, 1.8 cm; full thickness, 0.4 cm). The mean width ratio of the overall injured muscle to the entire bilateral muscle was 0.18. Muscle injury was more severe in the cases with bipedicled flap elevation and in those with 4 or more perforators harvested. Functional weakness was detected in 13 patients (17.1%). Multivariate analyses demonstrated that the width ratio of the muscle injury was an independent predictor of functional weakness. The width ratio achieved maximal discrimination regarding the rate of functional weakness at a threshold value of 0.12, indicating that functional weakness did not develop in all 19 cases with a width ratio of <0.12.Conclusions:The extent of rectus muscle injury during perforator dissection may be associated with functional donor morbidity after DIEP flap harvest. This may be beneficial in achieving proper balance between securing flap perfusion and preserving donor functions.

Differences in Electromechanical Delay Subsequent to Neuromuscular Fatigue: A Potential Relationship to Physical Fitness Training

Background: lower body strength is a vital factor in combat sports success. When combat sport athletes (CSA) performing workouts, leg muscles occupied in all technical, tactical, and movements actions. The prevalence of non-contact injuries in CSA and non-athlete remains high. As muscular strength contributes to joint constancy, neuromuscular fatigue is considered as a danger factor for noncontact impairments. Purpose: To examine and compare the impacts of fatiguing on electromechanical in 3 different physical fitness training groups (CSA, healthy, and sedentary). Study design: Randomized controlled laboratory study. Methods: Ninety male participants (mean ± SD: age = 22.16 ± 3.51) were included and divided into three groups each of 30 individuals (30 combat sport athletes [Boxing=10; Kickboxing=7; Taekwondo=5; Karate=5; Judo=4], 30 healthy individuals, and 30 sedentary individuals). Evaluation of EMD was performed pre-and-post fatiguing protocol using Biodex System isokinetic dynamometer and wireless 8-channel Delsys electromyography (EMG) telemetry system. The three groups performed periodical intermittent contractions utilizing a 0.6 duty cycle, including 6 s contraction followed by 4 s relaxation at 60% of maximum voluntary contractions till task-incompetence. Results: Repeated measures analysis of the variance (RMANOVA) was utilized to measure the main effect of time (pre-and-post-fatigue), speed (60, 180, and 300 ˚/s), within the physical condition (CSA, healthy, and sedentary), and interaction between them on EMD. In all three studied groups, EMD was consistently increasing (p<0.001) after increasing the speed. Main effect (p<0.001) for time and speed was detected across entire muscle groups. Also, significant interaction effect (p<0.001) between time and speed in all muscle groups. Irrespective of muscle, speed or time, mean EMD was greater in the sedentary group in comparison to CSA group (p<0.001) and healthy group (P = 0.011) respectively. Conclusion: The results reinforce that neuromuscular fatigue significantly increases EMD, which might lead to augment risk factors for injuries. Elevated rate of lower EMD were induced by physical condition. Raising angular velocity might affect neuromuscular functioning, causing a reduction of joints stability, and might to injuries. The increased electromechanical delay can affect maximal performance then augment the risk of injuries whether in CSA or others. Joining sport team physical fitness training sessions is a great prevention factor than being sedentary.

The use of a probe stabilizer to reduce musculoskeletal overload of ultrasound operators in routine diagnostic echocardiographic imaging

Introduction: Echocardiography is essential in the evaluation of patients with cardiovascular disease. Repetitive movements, however, expose ultrasound operators to a high risk of musculoskeletal strain injuries. Aim: We investigated to what extent a probe stabilizer could reduce repetitive movements. Materials and methods: The study population consisted of 31 male patients referred for routine transthoracic echocardiography. A good apical acoustic window was prerequisite for inclusion. Standard apical views and measurements were first recorded without using the probe stabilizer. Afterwards, the same apical views and measurements were acquired with utilization of the probe stabilizer. During the entire procedure, shoulder abduction and muscle activity of right forearm flexor and extensor muscles were recorded. To this purpose, an EMG-sensor was attached to the right lower arm and a gyroscope to the right shoulder blade. Results: Extreme right arm abduction (>30˚) occurred in 58% of the time with use of the stabilizer and in 98% of the time without (p <0.01). Activity of right forearm extensor muscles was 42% with and 60% without stabilizer (p = 0.04). For the flexor muscles these percentages were 47% and 87%, respectively (p <0.01). Use of the stabilizer did not affect the time needed for image acquisition (308s versus 309s, respectively, p = 0.46). Conclusions: This study demonstrated that the use of a stabilizer during acquisition of apical views in routine transthoracic echocardiography reduces the total time of shoulder abduction and the use of the right forearm muscles, while acquisition time was not affected.

Wooden breast – a novel myopathy recognized in broiler chickens

Abnormally hard breast fillet consistency began to emerge in commercial broiler chickens around 2010. Due to the remarkable muscle hardness, the condition acquired the vernacular name ‘wooden breast myopathy’. This myopathy starts to develop after two weeks of age at the earliest and typically proceeds into chronic myodegeneration in three to four weeks of age. The lesion begins focally and typically develops into a diffuse lesion that involves the entire major pectoral muscle. The restricted location of wooden breast lesion in the m. pectoralis major distinguishes it from several other myodegenerative diseases that widely affect the skeletal muscle system and often the cardiac and smooth muscle systems too. Although industry-wide incidence rates are difficult to assess, it has been estimated that approximately 5-10% of commercially produced breast fillets exhibit severe WB. Even at low incidence rates, the costs to industry are substantial, as breast fillets with the wooden breast condition are often downgraded and sold at a discount, used for further processing, or in extreme cases, discarded. Because the etiology of wooden breast is still unclear, in the future, study of the early lesions, pathogenesis and the possible reduction of animal welfare are likely to gain more attention.

Unilateral Pedicled Pectoralis Major Harvested by Endoscopic-Assisted Method Achieves Adequate Management of Sternal Infection and Mediastinitis.

Bilateral PM muscles or combination with rectus abdominis or omentum are commonly used for upper and lower sternal wound infections. Unilateral PM harvesting using endoscopic-assisted method may have a simple, safe, and reliable entire muscle harvesting with comparable result of less donor-site violation. A retrospective review was performed from 2003 till 2015 on 38 patients referred to a single plastic surgeon for treatment of sternal wound infection following median sternotomy for cardiovascular surgery. After the humerus insertion of PM was cut with the assistance of endoscope visualization, all the other PM insertions on the sternum, rib, and clavicle were divided, the unilateral pedicled PM can be advanced approximately 10 cm to cover the cephalad and caudal sternum, and fill the retrosternal mediastinum. Four re-explorations in three patients for postoperative hematoma occurred. No early recurrent infection for wound dehiscence experienced. Three patients died of multiple organs failures as 30-day mortality. Two patients underwent late recurrent infections; one patient had twice wire infection removals at 4 and 6 months after transfer, and the other had another PM for rib osteomyelitis in 3 years. Unilateral PM transfer is justified to provide a simple, reliable, straightforward procedure for sternal infection management and mediastinal obliteration without violation of second flap in compromised patients.