Anatomy Of Muscles Research Articles

Anatomical features of the extensor digitorum brevis muscle as a plastic material in reconstructive surgery of facial paralysis

Relevance. Facial paralysis is a common neurological illnesses of the maxillofacial region. Gold standard of dynamic correction of permanent facial paralysis is gracilis muscle transfer. However, using this flap is impractical or impossible in some cases. There are few domestic and international publications about extensor digitorum brevis muscle for facial reanimation surgery.Purpose. Assessment of muscle variability on the dorsum of the foot; analysis of blood supply and innervation of the extensor digitorum brevis muscle.Materials and methods. Operations performed on 10 unclaimed corpses: dissection of the extensor digitorum brevis muscle, as well as the blood vessels and nerves of the dorsum of the foot. The legal and ethical requirements for such studies were observed planning the design of the study and during work.Results. As a result, in 80% of cases, was found a typical anatomy of muscles, blood vessels, and nerves in the dorsum of the foot. In 10% was found a typical anatomy of muscles and nerves, but there was no lateral tarsal artery – the branch of the dorsal artery of the foot. Blood supply to the extensor digitorum brevis muscle performed by perforating branches of the peroneal artery. In 10% was found subtotal atrophy and fibrous degeneration of the extensor digitorum brevis muscle.Conclusions. The use of the extensor digitorum brevis muscle is a perspective method for the treatment of facial paralysis. Harvesting of this flap is complicated.

Educational Modules of Skeletal Muscle Anatomy and Function with Models and Active Data Gathering Related to Muscular Dystrophy

Educational Modules of Skeletal Muscle Anatomy and Function with Models and Active Data Gathering Related to Muscular Dystrophy

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).

Does resistance training increase aponeurosis width? The current results and future tasks.

The aponeurosis, a sheet of fibrous tissue, is the deep and superficial fascia where muscle fibers attach in pennate muscles. It is quite possible that the aponeurosis size increases in response to resistance training-induced fiber hypertrophy due to an increase in connection area. As a result, it leads to an increase in anatomical muscle cross-sectional area. However, attention has not been paid to aponeurosis area changes. This review sought to determine whether muscle hypertrophy changes aponeurosis width following short-term resistance training using an equation we modified [post/pre changes in aponeurosis width (AWpost/pre) = post/pre changes in anatomical cross-sectional area (CSApost/pre) ÷ post/pre changes in pennation angle (PApost/pre) ÷ post/pre changes in fascicle length (FLpost/pre)]. A search using two electronic databases (PubMed and Google Scholar) was conducted. Nine studies measured CSApost/pre, PApost/pre, and FLpost/pre of the vastus lateralis muscle by ultrasound and magnetic resonance imaging. There was a statistically significant 2.73 [95% CI 1.11, 4.36; p = 0.009] cm2 increase in CSApost/pre along with a statistically significant 1.21° [95% CI 0.44, 1.97; p = 0.002] increase in PApost/pre and a statistically significant 0.36cm [95% CI 0.19, 0.54; p = 0.0002] increase in FLpost/pre. These results yield an estimated 1% reduction in aponeurosis width. Our results suggest that while muscle CSA, pennation angle, and fascicle length all increase following short-term resistance training, the aponeurosis width is not altered.

Transpsoas Lumbar Interbody Fusion Without Psoas Stimulated Electromyography.

This is a retrospective case review. The objective of this study was to present an anatomic approach to transpsoas interbody fusion without psoas stimulated electromyography (sEMG) and to evaluate the rate of neurological and approach-related complications. The transpsoas approaches have become commonly utilized for lumbar interbody fusion and may have certain advantages compared with other methods of interbody stabilization. Traditionally, transpsoas approaches have been performed utilizing sEMG as it has been purported to reduce the risk of injury to the lumbar plexus; however, an anatomic approach to transpsoas surgery is also possible as cadaveric studies have demonstrated the anatomy of the psoas muscle and lumbar plexus. Patients who underwent transpsoas interbody fusion using an anatomic approach without psoas sEMG between 2005 and 2018 were enrolled in this study. The preoperative and postoperative medical records for this cohort were carefully reviewed to identify any new or persistent radicular symptoms, neurological deficits or approach-related complications. A total of 133 patients (48 males, 85 females) underwent transpsoas interbody fusion at 222 levels in this cohort-which had a mean age of 63 (61, 65) years and body mass index of 28.8 (27.8, 29.9). New neurological complications were seen in 5 patients (3.8%) and 5 patients (3.8%) were found to have new postoperative radicular pain, up to 3 months postoperatively. The total number of perioperative, approach-related complications was 7 (5.3%) for the entire cohort. An anatomic transpsoas approach to the interbody space without psoas sEMG demonstrated a rate of neurological and approach-related complications that was comparable or superior to the rate of complications reported using the traditional transpsoas approach with sEMG.

Muscle Function During Feeding Through Infancy

Infant mammalian feeding is a complex process that requires the integration of different behaviors and over twenty‐five muscles controlled by multiple cranial nerves. Despite extensive characterization of muscle activity during a feeding sequence, from suckling to swallowing, specific biomechanics of muscle function are unknown. The function of a muscle is determined by both when the muscle is active and the line of action of the muscle, as well as the change in length during activity. In mammals, there is potential for the line of action of the muscles involved in swallowing to change through ontogeny, as infants have a compressed oropharyngeal anatomy relative to adults. Additionally, while we understand when muscles are active during infant feeding, little has been done to understand whether those activity patterns correspond to concentric, eccentric, or isometric contractions. Here, we used contrast‐based microCT scanning coupled with electromyography (EMG) and fluoromicrometry to test the possibility that muscle function changes through infancy using our validated infant pig model. We collected anatomical data from pigs at infancy and just prior to weaning (21 days old), and isolated muscles of interest in Avizo. We collected EMG and fluoromicrometry data from five muscles involved in feeding (Geniohyoid, Digastric, Stylohyoid, Thyrohyoid, and Omohyoid) at the same ages. We found substantive changes in muscle anatomy through infancy and found extensive variation in muscle firing patterns and function within muscles. Some muscles (eg thyrohyoid) exhibited concentric contractions, whereas other muscles were eccentric (eg omohyoid). Still others exhibited multiple functions, and were eccentric during sucking EMG bursts, but isometric during swallowing EMG bursts (eg geniohyoid). Additionally, we found regional heterogeneity in muscle firing patterns in some muscles (eg stylohyoid), whereby electrodes placed in the middle of the muscle showed activity during swallows, but electrodes placed closer to the hyoid (more ventrally) recorded activity during sucking and swallowing. These results highlight the complexity of infant mammal feeding and demonstrate that muscle activity does not necessarily indicate muscle function. Instead, many muscles that are traditionally thought to function to pull the hyoid along their line of action may actually be functioning to stabilize the hyoid during swallowing. This suggests that control and coordination of the oropharyngeal structures is likely to be more important for successful feeding function than strength or the velocity of moving those structures.Support or Funding InformationAAA Postdoctoral Fellowship

Application of CT Imaging in the Analysis of Thigh Muscle Morphology of Athletes

The objective of the paper is to investigate and explore the effects of progressive muscle relaxation training (PMR) on image qualities of computed tomography (CT) coronary angiography and the relief of anxiety and pain of patients, as well as the improvement of sleep qualities of patients. The SPSS 16.0 statistics software was applied to respectively obtain the mean number, the standard deviation, and P value, etc. and analyze the variances of each group; the analysis was statistically significant at P < 0 05. The results of the study showed that CT could clearly indicate the anatomy of the thigh muscles and adjacent organs, and could better distinguish the bone density; however, its partitioning accuracy of the erector spinae was slightly worse. Therefore, it was inferred that morphological parameters such as CT values would provide persuasive data for clinical diagnosis, intervention therapy, and rehabilitation exercises, etc.

Neck Muscle Morphology and Function in Primates

The cervical spine lies at intersection between the cranium and postcranium and plays a crucial role in orienting the head relative to the substrate during locomotion. Previous work demonstrates that bony features of the cranial base and cervical spine are related to positional behavior in primates. How soft tissues of the neck vary across primate taxa is relatively unknown yet is critical for understanding function, head carriage, and locomotion in this clade. The objective of this study was to describe the relationship between the extrinsic and intrinsic muscles of the neck and postural and locomotor behaviors in primates. We collected and dissected 26 primate cadavers from 17 different genera representing each major primate clade. We hypothesized that trunk and neck posture, as well as forelimb dominated below‐branch suspensory behaviors and neck rotational capabilities all influence the attachment sites and size of the dorsal neck musculature.Using gross anatomical dissection, we qualitatively described and compared the attachment sites of the dorsal neck, back, and shoulder muscles of taxa that display contrasting behaviors and quantified muscle mass. Using the dissection data combined with contrast enhanced microCT data, we constructed 3D models of the head and neck to visualize the in situ neck muscle attachment sites for Propithecus, Aotus, and Carlito.Gross anatomical dissections demonstrate that among nonhuman apes, hylobatids lack cranial attachments of the trapezius and rhomboideus. Additionally, strepsirrhines display anatomy that is more nonprimate mammal‐like in the distribution of the trapezius, rhomboideus, and semispinalis muscles. Results of phylogenetic regressions indicate that neck muscle masses are best predicted by body size, but also demonstrated significant results for both postural and locomotor behaviors as predictors of overall muscle mass (p < 0.05). This study represents the first comprehensive description of the functional anatomy of the neck muscles across primates. Future work will focus on quantifying biomechanically‐relevant variables such as physiological cross‐sectional area using novel fascicle‐tracking methods and estimating muscle moments to compare across taxa.Support or Funding InformationThis work was funded by the Leakey Foundation, National Science Foundation, American Association of Anatomists, Western University of Health Sciences, and University of Missouri.

Anatomy of the Lateral Pterygoid Muscle and its Relationship with Temporomandibular Disorders. An anatomic review

The lateral pterygoid muscle (LPM) is a chewing muscle that is found bilaterally in the cranial region, anatomically the LPM is made up of two bellies, an upper belly and a lower belly. The anatomical description of the LPM present in the scientific literature, showed that there is an anatomical difference or variation mainly in the insertions of the upper belly of the LPM at the level of the temporomandibular joint and specifically in the disc and articular condyle, although distributions are reported similarly they are not entirely accurate, in smaller quantities some articles reported variations in the insertion of the lower belly, and in others the appearance of a third belly of the LPM or middle belly. As mentioned above, a high number of studies that presented some type of LPM variation was associated with some type of TMD of the joint or some of its intra or extra‐articular components. A review of the literature in scientific databases was carried out after the selection of the scientific articles, which were analyzed in full text and the relationship on the anatomy of the LPM and the TMD was sought.Support or Funding InformationNo conflicts of interest declared.Search AlgorithmFigure 1 Correlation between the anatomical variation of the LPM and the TMD Bibliographic reference Anatomic Variation of the LPM TMJ Dissorder Antonopoulou M, et al. (2013) 3 insertions in the joint disc. Dysfunction in the anterior displacement of the articular disc. Coskun A, et al. (2009) 3 heads of the lateral pterygoid muscle. Temporomandibular dysfunction Dergin G, et al (2012) Provision in patterns of variation in the insertion of the MPL, either in the articular disc and in the condyle. No correlation was presented. Desmons S, et al (2007) Provision in patterns of variation in the insertion of the LPM, either in the articular disc and in the condyle. Temporomandibular dysfunction Imanimoghaddam M, et al. (2013) Provision in patterns of variation in the insertion of the LPM, either in the articular disc and in the condyle Temporomandibular dysfunction Kawakami S, et al (2012) Variation in the insertion of the lower head of the LPM. Temporomandibular dissorder. Litko M, et al (2016) Variation in the insertion of the lower and upper head of the LPM, plus third head of the LPM. Indirect correlation between insertion and joint disc abnormalities. Matsunaga, et al (2009) Variation in the insertion of the lower head of the LPM. No correlation was presented. Mazza D, et al (2009) Variation in the insertion of the upper and lower head of the LPM. Temporomandibular dysfunction, dislocation of the joint disc. Omami G, et al (2012) Variation in the insertion of the upper head of the LPM. Symptomatic TMJ only with the presence of pain evaluated with VAS. Melke G, et al (2016) Variation in the insertion of the upper head of the LPM. Temporomandibular dysfunction.

Myology of the Reptilia

Sauropsid vertebrates (lepidosaurs, turtles, crocodilians and birds) have evolved a diversity of head shapes and feeding behaviors during their history. A key to understanding this great radiation of reptiles is the physiology of the jaw musculature which powers the feeding apparatus. However we still know little about jaw muscle mechanics within lineages of reptiles or how this complicated musculoskeletal system has evolved to employ a variety of behaviors. New imaging and computational methods are now enabling an extraordinary view into the 3D anatomy and biomechanics of reptiles and other vertebrates. Here we illustrate several approaches to analyzing jaw muscle morphology and architecture using contrast imaging, 3D fiber tracking, biomechanical analysis, and data visualization methods that offer enormous potential for exploring the anatomy, function and evolution of jaw muscles. We first illustrate basic workflow of 3D jaw muscle visualization, morphometrics and interpretation using crocodilian jaw muscle anatomy. Second, we show how homologous jaw muscle bellies evolve among lineages of different reptiles and birds to elicit different functional demands. Third, we show how the 3D architecture of hard‐to‐dissect, small, deep protractor muscles correlate with different types of cranial kinesis among a sample of lizards and birds. These new imaging and analytical approaches offer incredible potential for the quantification of soft tissue morphology like muscle architecture and their applications to comparative biomechanics, ecomorphology, and evolutionary biology should prove remarkable.Support or Funding InformationNSF IOS 1457319, NSF EAR 1631684, University of Missouri Life Sciences Fellowship, University of Missouri Integrative Anatomy Fellowship, IMSD‐Express

Case Based Learning Using a Dynamic 3D Model: An Integrated Approach in Teaching Anatomy

Medical students have different levels of spatial competence. Some students can look at a well‐prepared 2D figure and understand all of the shapes and structure relationships. However, most students have to do that with difficulty and process it from wrong aspects. 3D model allows the student to integrate all of those aspects into one object that can be seen from different angles. Different 3D designs save a lot of time for the students as well as the instructors. In addition, making these 3D models movable (dynamic 3D) allows for creative reflections and problem solving in practice. The students can have the opportunity of establishing new instruments that build the teamwork through shared activities. Recruiting dynamic 3D models in anatomy teaching also favors implementation of effective instructional approaches with active participation by the students.This study aims to describe a novel intervention in teaching the anatomy of the extraocular muscles by incorporating a dynamic 3D model and utilizing a case based learning methodology. We created a dynamic 3D model demonstrating the extraocular muscles surrounding the eyeball (fig 1). The anatomist demonstrated attachments, nerve supply and action of the extraocular muscles on the model. The students were able to pull each muscle and notice the movement of the eyeball. Ophthalmologist is then involved in the study by demonstrating strabismus case followed by explanation of the different effects of nerve injuries in which paralysis of the extraocular muscles occurs and led to different types of strabismus.The students were allowed to reflect on the Case Based Learning. They were asked to voluntarily participate in an anonymous questionnaire. The items in the questionnaire form obeyed Likert‐type rating scales in which the respondent show the level of agreement or disagreement according to five point Likert scale. In addition, focus group discussion was conducted to discuss if this reflected on their way of anatomy learning.ResultsEighty‐two third year medical students participated in this study. Almost Sixty‐one percent (n=50) of the students enjoyed the session. Ninety percent (n=74) described the dynamic 3D as more helpful in the application of knowledge than the 2D or static 3D models. Sixty‐seven percent (n=55) mentioned that the dynamic 3D model increased their deep and spatial understanding. Sixty‐three percent (n=52) of the students demonstrated that integration between basic and clinical data through involving of clinician with the teaching faculty promotes better understanding of the clinically relevant topics. Some students in the focus group described the integrated basic and clinical teaching as the best way to demonstrate the relevance of the anatomical data taught in their basic science years.ConclusionThe use of dynamic 3D models could be superior to traditional teaching in consolidating the understanding and the relevance of the anatomical relations. That can be achieved through integrating basic anatomy teaching with clinician involvement using case based learning.Dynamic 3D model demonstrating the extraocular muscles movementFigure 1

Muscle and Joint Evolution in Crocodyliforms

Modern crocodylians employ immense forces during feeding relative to other clades. Many characters that enable crocodylians to generate and resist these forces are not found in their ancestors, and thus the evolution of crocodylians involved a substantial reorganization of the feeding apparatus. This transformation saw changes to many cranial joints: the expansion of the pterygoid buttress, reshaping and reorienting of the articular surface of the jaw joint, and the suturing of the quadrate and palate to the braincase, closing the primitive and potentially‐kinetic otic and palatobasal joints. The jaw muscles that loaded cranial joints also experienced reorganization: the flatter skull of crocodylians led to mediolateral orientations, the pterygoideus ventralis muscle began attaching laterally on the mandible, and the retroarticular process enlarged caudally, expanding the size of the depressor mandibulae muscle. Once this suite of changes was in place, crocodyliforms radiated into forms with derived diets and craniodental modifications. However, the biomechanical effects of these morphological character shifts on feeding performance have not been explicitly evaluated, obscuring coevolutionary patterns of morphology and function. Here, we use select crocodylians and fossil relatives that characterize the evolution of the clade to reconstruct jaw muscle anatomy and estimate biomechanical loading of cranial joints. We hypothesize that crocodylians will be characterized by successive increases in jaw muscle mass relative to body size. We used CT data to create 3D models of extant and fossil suchians that demonstrate the evolution of the crocodylian skull, using osteological correlates to reconstruct muscles. Muscle forces were distributed with the computational package Boneload and used as input for finite element analysis and 3D lever analyses. We found that jaw muscles expanded and shifted attachments throughout suchian evolution: muscle orientations became more mediolateral as the skull flattened, the pterygoideus ventralis muscle began inserting on the lateral mandible, and the depressor mandibulae muscle expanded its attachment on the enlarged retroarticular process. Changes to cranial joints accompanied muscular changes: the pterygoid buttress expanded, the articular surfaces of the jaw joint changed, and the quadrate and palate sutured to the braincase. Our results showed that joint force orientation tracks with articular surface metrics. We found that as bite location moves caudally, working side joint force decreases in magnitude; it is likely that in feeding events such as shaking bites or death roll, the jaw joint is loaded in tension. This study depicts a feeding apparatus that defies traditional understanding. The combination of dual craniomandibular joints and jaw joints loaded in tension is unknown from other tetrapods.Support or Funding InformationNSF‐EAR 1631684Cladogram of representative crocodiles included in the study. The black arrows represent the orientation of joint reaction force; note that joint reaction force becomes more horizontally oriented in later specimens.Figure 1

MP30-13 USE OF UNIFORMLY SIZED MUSCLE FIBER FRAGMENTS FOR THE TREATMENT OF URINARY INCONTINENCE

You have accessJournal of UrologyUrodynamics/Lower Urinary Tract Dysfunction/Female Pelvic Medicine: Female Incontinence: Therapy I (MP30)1 Apr 2020MP30-13 USE OF UNIFORMLY SIZED MUSCLE FIBER FRAGMENTS FOR THE TREATMENT OF URINARY INCONTINENCE In Kap Ko, Eun Sang Yoo, Sang Mi Park, Bu-Kyu Lee, John Jackson*, Ji Hyun Kim, James Yoo, and Anthony Atala In Kap KoIn Kap Ko More articles by this author , Eun Sang YooEun Sang Yoo More articles by this author , Sang Mi ParkSang Mi Park More articles by this author , Bu-Kyu LeeBu-Kyu Lee More articles by this author , John Jackson*John Jackson* More articles by this author , Ji Hyun KimJi Hyun Kim More articles by this author , James YooJames Yoo More articles by this author , and Anthony AtalaAnthony Atala More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000000869.013AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Treatment of muscle function loss due to traumatic injury, congenital defects, or tumor ablations is clinically challenging. The current treatment standard is grafting of autologous muscle flaps, however significant donor site morbidity and graft tissue availability remain a problem. Alternatively, muscle fiber therapy has been attempted to treat muscle injury by transplanting single fibers into the defect site. However, irregularly organized long fibers resulted in low survivability due to delay in vascular and neural integration, thus limiting the therapeutic efficacy. Therefore, no effective method is available to permanently restore extensive muscle injuries. To address the current limitations, we developed a novel method that produces uniformly sized native muscle fiber fragments (MFFs) for muscle transplantation. We hypothesized that fragmentation of muscle fibers into small and uniformly sized fragments would allow for rapid reassembly and efficient engraftment within the defect site, resulting in accelerated recovery of muscle function. In this study, we applied autologous MFFs to restore sphincteric muscle anatomy and function for the treatment of urinary incontinence. METHODS: We developed an MFF processing method that produces uniformly sized fragments (approximately 100 μm in width and length) with intact muscle cells on the fiber surface. To test the therapeutic effects of the MFF technology, we created several rodent muscle injury models, including 1) a muscle atrophy model using toxin treatment such as barium chloride (BaCl2), 2) a volumetric muscle defect model by surgical ablation, and 3) urinary incontinence (UI) model by damaging the external sphincter of urethra. The effectiveness of the MFF therapy was determined by structural and functional recovery of muscle tissues in these models. RESULTS: The processed MFFs have a dimension of approximately 100 μm and contain living muscle cells on extracellular matrices (ECM). In preclinical animal studies using muscle atrophy, volumetric defect, and urinary incontinence models, histological and functional analyses confirmed that the transplanted MFFs into the injury sites were able to effectively integrate with host muscle tissue, vascular, and neural systems, which resulted in significant improvement of muscle function and mass. CONCLUSIONS: These results indicate that the MFF technology platform is a promising therapeutic option for the restoration of muscle function in several muscle defect models, including the urinary incontinence. The ease of preparation and short processing time makes this technology readily usable as a point of care procedure in the operating room. Source of Funding: Departmental funding © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e443-e443 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information In Kap Ko More articles by this author Eun Sang Yoo More articles by this author Sang Mi Park More articles by this author Bu-Kyu Lee More articles by this author John Jackson* More articles by this author Ji Hyun Kim More articles by this author James Yoo More articles by this author Anthony Atala More articles by this author Expand All Advertisement PDF downloadLoading ...

Temporal tendinosis: A cause of chronic orofacial pain.

Diverse musculoskeletal disorders and neuropathic symptoms of the face pose significant diagnostic challenges. In particular, temporal tendinosis is generally overlooked in the medical and dental literature and is therefore a poorly understood topic and often problematic cause of chronic orofacial pain. In this article, we explore temporal tendinosis as a cause of unresolved orofacial pain by reviewing the complex anatomy of the temporalis muscle, common presentations of temporal tendinosis, possible etiologies for injury and place a strong emphasis on required diagnostic evaluation and clinical management. Temporal tendinosis remains under diagnosed due to a combination of anatomical complexity and incomplete description in the majority of general anatomy medical textbooks. The two main presentations are unilateral facial pain with or without temporal headache and pain radiating from the distal temporalis tendon to the temporalis muscle. Diagnosis should be made with a combination of focused history, physical examination and specialised imaging, preferably with ultrasound but with MRI an alternate option. While many management options are available, optimal treatment remains unclear. Temporal tendinosis is an under-recognised and under-treated condition. Despite the fact that orofacial pain is one of the single most common complaints of patients presenting to physicians or dentists, it is widely acknowledged that training for diagnosis and manage of temporal tendinopathy among primary care physicians in both medical and dental professions is inadequate. This may result in extensive workups, leading to suboptimal management and chronic pain syndromes.

Shoulder Muscle Architecture in the Echidna (Monotremata: Tachyglossus aculeatus) Indicates Conserved Functional Properties

Monotremes are a group of egg-laying mammals, possessing a mosaic of ancestral and derived anatomical features. Despite much interest in monotremes from phylogenetic, morphological, and ecological perspectives, they have been the subject of relatively few biomechanical studies. In this study, we examined shoulder and proximal forelimb muscle anatomy and architecture in the short-beaked echidna, Tachyglossus aculeatus, through contrast-enhanced computed tomography and gross dissection. Muscle architecture is a major determinant of muscle function and can indicate specialized muscle roles, such as the capacity for generating large forces (through large physiological cross-sectional area, PCSA) or working ranges (through long fascicle lengths). We hypothesized that some muscles would exhibit architectural specializations convergent with other fossorial and/or sprawling animals, and that other muscles would reflect the echidna’s unusual anatomy and locomotor style. Instead, we found the shoulder and proximal forelimb muscles in echidna to have little variation in their architecture. The muscles generally had long fascicles and small-to-intermediate PCSAs, consistent with force production over a wide working range. Further, muscles did not show overt differences in architecture that, in therian mammals, have been linked to increased forelimb mobility and the transition from sprawling to parasagittal posture. Our measures of architectural disparity placed the echidna closer to the tegu lizard than other sprawling fossorial mammals (e.g., mole). The low architectural diversity found in the echidna’s shoulder and proximal forelimb muscles is interpreted as a lack of functional specialization into distinct roles. We hope our study will contribute to greater understanding of monotreme anatomy and biomechanical function, and to the reconstruction of musculoskeletal evolution in mammals.

Comparative anatomy of the fin muscles of non-sarcopterygian fishes, with notes on homology and evolution

Limited gross anatomical information about the muscles of fins, in particular those of the median fins, creates substantial gaps in the comparative anatomy, homologies, and evolution of these muscles across fishes. The scarcity of data also makes it difficult to interpret results obtained in developmental studies done in model organisms, such as zebrafish. To overcome these gaps, we provide descriptions of the configuration of all appendicular muscles of Amia, median fins of Polypterus, and the dorsal and anal fins of Lepisosteus and Chondrostei. The musculature of other species, including sharks and sturgeons, is also revised. We describe muscles that were previously overlooked, report sexual dimorphism in the muscles of the anal fin of Polypterus, and reveal muscle variations within Polypterus males. Species dissected for the present study thus represent all major non-sarcopterygian extant clades of gnathostomes, i.e. Chondrichthyes, Polypteriformes, Chondrostei, Lepisosteiformes, Amiiformes and Teleostei. Moreover, we compare our observations with the relatively few works that have provided information about muscles of at least some fins of these taxa in order to provide a broad discussion on - and detailed schemes showing - the major evolutionary patterns within the appendicular musculature of these fishes. Such discussion provides an opportunity for a more comprehensive understanding of appendicular evolution and fish evolution in particular and of gnathostome and morphological evolution in general.

Left Valvar Morphology Is Associated With Late Regurgitation in Atrioventricular Canal Defect

Left atrioventricular valve regurgitation (LAVVR) after atrioventricular canal (AVC) repair remains a significant cause of morbidity. Papillary muscle arrangement may be important. To investigate the implications of left mural leaflet morphology, we examined anatomic characteristics of the LAVV to determine possible associations with postoperative LAVVR. All patients with biventricular AVC repair at our institution between January 1, 2011, and December 31, 2016, with necessary imaging were retrospectively reviewed. We assessed papillary muscle structure and novel measures of the left mural leaflet from preoperative echocardiograms and the degree of LAVVR from the first and last available follow-up echocardiograms. Associations with degree of early and late postoperative LAVVR were assessed with t tests, analysis of variance, or χ2 or Fisher exact tests, and multivariable logistic regression. There were 58 of 156 patients (37%) with significant (moderate or severe) early postoperative LAVVR, and 30 of 93 (32%) had significant LAVVR after 6 or more months. Fewer patients with closely spaced or asymmetric papillary muscles had moderate or severe late LAVVR vs those with widely spaced papillary muscles (17% vs 40%, P= .019). Controlling for weight at operation, genetic syndromes, and bypass time, widely spaced papillary muscles increased the odds ratio for late LAVVR to 3.6 (P= .026). Larger mural leaflet area was also associated with late LAVVR on univariable (P= .019) and multivariable (P= .023) analyses. One-third of patients with significant late LAVVR had no significant early postoperative regurgitation. Mural leaflet and papillary muscle anatomy are associated with late LAVVR after AVC repair. Late regurgitation can develop in the absence of early LAVVR, suggesting different mechanisms.

Botox Effect on Sex Hormones and Lipid Profile of Females Rats

The present study aimed to investigate the effect of Botoxon sex hormones level which including folliclestimulatinghormone (FSH), luteinizing hormone(LH)and progesterone in female rats and measurement ofserum lipid profile. Two doses 0.1/animal and 0.2 ml/animal from Botox were used and the animals wereinjected intramuscular of botulinum toxin for 1 day as two doses only. The results showed a significantdecrease (P<0.05) in the level of FSH and LH, with a significant increase the level of progesterone of thefemale treated with 0.1 ml and 0.2 ml of Botox compared with the control group. The results showed asignificant increase in the level of cholesterol, TG, HDL, LDL and VLDL of the female treated with Botoxatdose 0.2 ml when compared with the control group. While,the female treated with Botoxat dose 0.1 mlthere was no a significant in level of cholesterol compared with control group. Also, there was a significantdecrease of HDL of female rats treated with Botox compared with control group. Injections of femalerats with botulinum toxin are generally well tolerated and side effects are few. A precise knowledge andunderstanding of the functional anatomy of the mimetic muscles is absolutely necessary to correctly usebotulinum toxins in clinical practice.

Distal insertional anatomy of the triceps brachii muscle: MRI assessment in cadaveric specimens employing histologic correlation and Play-doh® models of the anatomic findings.

Assess the insertional anatomy of the distal aspect of the triceps brachii muscle using magnetic resonance imaging (MRI) in cadavers with histologic correlation and Play-doh® models of the anatomic findings. Elbows were obtained from twelve cadaveric arm specimens by transverse sectioning through the proximal portion of the humerus and the midportion of the radius and ulna. MRI was performed in all elbows. Two of the elbow specimens were then dissected while ten were studied histologically. Subsequently, Play-doh® models of the anatomic findings of the distal attachment sites of the triceps brachii muscle were prepared. MRI showed a dual partitioned appearance of the distal attachment sites into the olecranon in all specimens. In the deeper tissue planes, the medial head muscle insertion was clearly identified while superficially, the terminal portion of the long and lateral heads appeared as a conjoined tendon. Histologic analysis, however, showed continuous tissue rather than separate structures attaching to the olecranon. Although MRI appeared to reveal separate and distinct attachments of the triceps brachii muscle into the olecranon, histologic analysis delineated complex but continuous tissue related to the attachments of the three heads of this muscle. The Play-doh® models were helpful for the comprehension of this complex anatomy and might serve as a valuable educational tool when applied to the analysis of other musculoskeletal regions.

In vivo characterization of skeletal muscle function in nebulin-deficient mice.

The conditional nebulin knockout mouse is a new model mimicking nemaline myopathy, a rare disease characterized by muscle weakness and rods within muscle fibers. We investigated the impact of nebulin (NEB) deficiency on muscle function in vivo. Conditional nebulin knockout mice and control littermates were studied at 10 to 12 months. Muscle function (force and fatigue) and anatomy (muscles volume and fat content) were measured in vivo. Myosin heavy chain (MHC) composition and nebulin (NEB) protein expression were assessed by protein electrophoresis. Conditional nebulin knockout mice displayed a lower NEB level (-90%) leading to a 40% and 45% reduction in specific maximal force production and muscles volume, respectively. Nebulin deficiency was also associated with higher resistance to fatigue and increased MHC I content. Adult nebulin-deficient mice displayed severe muscle atrophy and weakness in vivo related to a low NEB content but an improved fatigue resistance due to a slower contractile phenotype.