Anatomy Of Muscles Research Articles

Gross Anatomy of the Equine Masseter Muscle: Lamination and Intramuscular Course of the N. Massetericus.

The masticatory muscles of the horse are arranged in an asymmetrical pattern. Four individual muscles on the medial side of the mandible are opposed by one muscle (M. masseter) on the lateral side. However, recent studies on various herbivorous mammals indicate that the masseter muscle features a complex stratigraphic structure that might account for a functional diversity resembling an arrangement of several individual muscles. The functional consideration of the multidirectional equine masticatory movements leads to a similar hypothesis. In order to elucidate the detailed anatomy of the equine masseter muscle, eight cadaveric equine heads were dissected. Additional 29 skull specimens were assessed with regard to the masseteric attachment within the Fossa masseterica. A constant arrangement of nine individual muscular layers within the masseteric muscle was determined. The individual layers were clearly separated by tendon plates and their attachment areas at the masseteric fossa of the mandible were arranged in a constant pattern of bony ridges. With similar consistency, the main trunk of the masseteric nerve was found to run from dorsocaudal to ventrorostral: On that course, the nerve penetrated between the muscular layers from medial to lateral at constant positions. The findings of this study serve as a basis for further studies with the aim of developing biomechanical concepts of equine masticatory movement.

Anatomy and Immunohistochemistry of Woodpecker Tail Muscles.

Woodpeckers (Order Piciformes) belong to a group of birds characterized by their hammering capabilities in which the bill is utilized as a tool to probe for food and to excavate nest cavities. They have numerous specializations for this behavior, including their bill and tongue, feet for gripping vertical tree trunks, and tail feathers with thickened shafts to provide stability as a postural appendage. We hypothesized that (1) woodpecker tail musculature is also modified for clinging behaviors with a heterogeneous distribution of fast and slow muscle fibers, and that (2) the tree-trunk foraging Hairy Woodpeckers would have more slow muscle fibers in their M. depressor caudae than Northern Flickers, which forage on the ground where they probe the substrate for insects. We performed immunohistochemistry to identify the fiber type distributions for tail muscles Mm. caudofemoralis pars caudalis, lateralis caudae, levator caudae, and depressor caudae in four Hairy Woodpeckers and five Northern Flickers. Our results show that these tail muscles in the two woodpecker species are comprised of a majority of fast muscle fibers common among dynamic locomotor muscles. Interestingly, we report a functionally-significant distribution of slow muscle fibers in M. depressor caudae predicted to be utilized in propping of the tail during tree climbing and support. Further, we found more slow fibers (13.80% ± 4.49%) in the trunk-foraging Hairy Woodpeckers compared with the ground-foraging Northern Flicker (7.40% ± 4.95%), which we interpret to be related to the trunk-foraging habits of Hairy Woodpeckers.

Pelvic Floor Muscle Anatomy and its Contribution to Penile Erection in Olive Baboons.

Despite the number of studies on the contribution of pelvic floor muscles (PFM) to the penile erection process, their significance is still underestimated. The goal of this study was to investigate the role of PFM in the erection process in non-human primates. First, we performed an anatomical study of the penile structures in 12 baboon cadavers. Next, we created chronic electrophysiological models of normal erectile function in 25 olive baboons. We implanted electrodes on the cavernous nerves to control penile blood filling and placed other electrodes on the pudendal nerve to stimulate the ischiocavernosus muscles (ICM) contractions after sufficient blood filling, thus simulating both vascular and muscular phases of penile erection. We controlled the intracavernous pressure (ICP) during nerve stimulations and further performed a mathematical analysis of the collected data. We described the main pro-erectile muscle anatomy and its relationship with penile structures in monkeys. During neurostimulation studies, we showed the key role of ICM in achieving full penile rigidity with suprasystolic ICP up to 120-300 mm Hg. We also developed a math model for calculating the pro-erectile muscle's contraction force with high accuracy. In this study, we demonstrated the crucial role of PFM in the penile erection process using the monkey model, supporting the previous studies' data. We consider these results essential for a better, more complex understanding of the penile erection process and the participating structures in each stage. This is essential for further improving and designing novel erectile dysfunction diagnostics and treatment techniques.

Quantitative anatomy of the infraspinatus muscle in the human fetus.

The study presents one of the six scapulohumeral muscles, which occupies most of the osteofibrous infraspinatus compartment. Along with the supraspinatus, teres minor and subscapularis muscles, the infraspinatus muscle contributes to the rotator cuff. It protects the posterior aspect of the articular capsule of the shoulder joint, adducts and externally rotates the arm. The aim of the study was to perform the quantitative analysis of the infraspinatus muscle in human fetuses and to elaborate growth dynamics for its morphometric parameters. Using anatomical dissection, digital image analysis (NIS Elements AR3.0) and statistics (Student's t-test, regression analysis), the vertical, transverse and oblique diameters, muscle circumference and projection surface area of the infraspinatus muscle were measured in 36human fetuses of both sexes (17♂, 19♀) aged 18-30weeks. The infraspinatus muscle revealed neither sex nor laterality differences. All examined morphometric parameters of the infraspinatus muscle increased commensurately in accordance with the following linear functions: y=-4.024 + 0.903×Age ± 0.621 (R²=0.96) for transverse diameter, y=-3.089 + 1.321×Age ± 0.897 (R²=0.97) for vertical diameter, y=-1.161 + 0.632×Age ± 0.444 (R²=0.97) for oblique diameter, y=-13.575 + 3.851×Age ± 1.938 (R²=0.98) for muscle circumference and y=-293.512 + 23.228×Age ±19.650 (R²=0.95) for projection surface area.

The Relationship Between Glabellar Contraction Patterns and Glabellar Muscle Anatomy: A Magnetic Resonance Imaging-based Study.

Glabellar contraction patterns were introduced to the scientific literature to help guide glabellar neuromodulator injection algorithms. However, the relationship between the underlying musculature and its influence on these glabellar contraction patterns is unclear. The aim of this study was to identify via Magnetic Resonance Imaging (MRI) glabellar muscle parameters that display an influence on the distribution of individual glabellar contraction patterns. Thirty-four healthy young individuals of Caucasian Polish descent were investigated (17 women, 17 men) with a mean age of 23.6 years and a mean BMI of 22.8 kg/m2. MRI-based measurements of length, thickness, width and surface area of procerus, corrugator supercilii, orbicularis oculi and frontalis muscles were conducted. Unadjusted models revealed that there was no statistically significant difference between the five glabellar contraction types and the investigated muscle parameters indicating that independent of the skin rhytid pattern, the underlying musculature was not different between the investigated groups in this sample with all p ≥ 0.102. Adjusted models revealed that sex was the most influential factor due to males displayed in general higher values for the investigated parameters when compared to females. The results of this study reveal that based on the MRI parameters investigated and based on the investigated cohort, there does not appear to be a strong relationship between glabellar contraction patterns and underlying glabella muscle anatomy. Utilizing glabellar contraction patterns to design neuromodulator treatment algorithms may be of variable clinical merit.

Dynamic and static nasolabial muscle anatomy of unilateral cleft lip adult patients based on magnetic resonance imaging data.

This study aims to obtain a three-dimensional reconstruction model based on magnetic resonance imaging (MRI) data of patients with different degrees of unilateral cleft lip and analyze the anatomy and changes in multiple groups of nasolabial muscles under dynamic and static conditions. One normal person and four adult patients with unilateral cleft lip were included, and MRI was performed under static (upper and lower lips closed naturally) and dynamic (pout and grin) conditions. 3D Slicer software was used to reconstruct the model and draw the anatomic morphology of nasolabial muscles. The distance between the junction (where the muscle merges into the orbicularis oris) of the levator muscle, zygomaticminor muscle, and zygomatic major muscle to the median sagittal plane, the starting point to the junction point, the dynamic and static junction points, and the angle between the connection of dynamic and static junctions and the horizontal plane were measured under three kinds of movements, and the ratio was calculated. In all patients, under dynamic and static conditions, the distance from the muscle junction to the median sagittal plane, their ratios of the cleft side to the non-cleft side were all greater than 1. While the ratio of the distance from the starting point of the muscle to the junction point is less than 1. At static conditions, the two ratios of the same muscle increased gradiently with the severity of the cleft, and the ratio of the zygomatic minor muscle was prominent in the same patient. The ratio of the cleft side to the non-cleft side was greater than 1, and the value for comparison was the angle of the line from the static to the dynamic junction and the horizontal plane. The symmetry of the insertion site of the orbicularis oris and the linear distance of both sides of the muscle are related to muscle and cleft types. The angle of muscle contraction on the cleft side is greater than that on the non-cleft side.

When the Going Gets Tough: A Review of Total Hip Arthroplasty in Patients with Ipsilateral Above- and Below-Knee Amputation.

Life expectancy and overall function of amputated patients have improved significantly over the last few decades; for this reason, amputees are more exposed to primary or secondary degenerative disease of the hip, requiring total hip arthroplasty (THA) surgery. However, during training, not all the surgeons acquire adequate skills to manage these patients, and only a few studies and case reports describe technical pearls and outcomes of THA in patients with ipsilateral lower limb amputation, either above or below the knee. The objective of this narrative review is to present current evidence and surgical tips for performing THA in ipsilateral amputated patients, with a focus on the differences between patients with above- (AKA) and below-knee amputation (BKA). We reviewed manuscripts in major scientific databases, cross-referencing to retrieve adjunctive manuscripts, and summarized all relevant cases. We found 17 manuscripts, spanning 70 years of literature, collecting a total of 39 patients who underwent THA on an ipsilateral amputated limb: 13 AKA, 23 BKA, and 3 through-knee-amputation (TKA). The cohort primarily consists of patients with post-traumatic hip arthritis, often associated with sequelae such as fractures to other bones, soft tissue compromise and heterotopic calcifications. Managing with amputated patients requires careful planning, which includes the study of the residual bone, muscle anatomy, and the level of femoral amputation, as these factors present significant surgical challenges, especially in patients without a knee joint. In dealing with the post-traumatic and multi-comorbidity patients, rehabilitation goals should be considered prior to surgery and should drive the surgical strategy. We found that BKA patients typically have high functional demands, necessitating precise positioning of the components and an aggressive post-operative physiotherapy regimen to avoid unsatisfactory outcomes. AKA patients, on the other hand, often present with altered anatomy, and typically require more surgical instruments and expertise to achieve intraoperative dislocation of the hip joint.

Nonspherical humeral arthroplasty increases internal rotation: a biomechanical comparison of the native humeral head to nonspherical and spherical humeral implants

BackgroundNonspherical humeral head implants more closely resemble native humeral anatomy than spherical components and may better replicate native shoulder range of motion (ROM) and kinematics. The purpose of this study was to compare shoulder ROM and kinematics of a commercially available nonspherical humeral head implant with the native humeral head and a height matched, custom manufactured spherical implant. MethodsSix fresh frozen cadaveric shoulder specimens were used with a custom shoulder testing system. The native shoulder was tested in multiple positions under anatomic muscle loading. Each specimen was tested for ROM and glenohumeral joint kinematics by measuring the humeral head apex and humeral head center (HHC) translation per degree of rotation using a MicroScribe digitizer. Measurements were then repeated after implantation of a spherical and, subsequently, a nonspherical humeral head prothesis. ResultsThe nonspherical implant had significantly more internal rotation (IR) compared to the spherical implant at 0° abduction (10.6 ± 6.2° more IR, P = .004, 95% confidence interval [CI]: −13.3, 34.5), 30° abduction (5.7 ± 2.8°, P = .009, 95% CI: −12.6, 24.0) and 60° abduction (6.8 ± 2.7°, P = .002, 95% CI: −8.3, 22.1) in the scapular plane, and 60° abduction (6.9 ± 2.0°, P = .031, 95% CI: −12, 25.6) in the coronal plane. The nonspherical implant had more IR than the native head at 60° of abduction in the scapular plane (7.0 ± 2.2° P = .002, 95% CI: −10.3, 24.3). The spherical head had less IR than the native head at 0° abduction (7.2 ± 4.8°, P = .031, 95% CI: 32.5, 18.1). There were no differences in humeral head apex translation per degree of rotation noted between the spherical implant or nonspherical implant and the native shoulder. The nonspherical head had less HHC translation than the native shoulder at 30° abduction in the forward flexion plane (P = .007); otherwise, there were no statistically significant differences in HHC translation between the native shoulder, the spherical head, and the nonspherical head. There was no significant difference observed between the average difference in anterior-posterior and superior-inferior radius of curvature of the nonspherical implants (2.0 ± 0.7 mm) and the native humeral heads (1.9 ± 1.3 mm) [P = .926]. ConclusionThe results of this biomechanical study suggest that the commercially available nonspherical humeral head has improved IR when compared to a custom, height controlled spherical implant and offers ROM and kinematics similar to the native humeral head in a cadaveric model.

Comparative muscle anatomy of the anuran pelvis and hindlimb in relation to locomotor mode.

Frogs have a highly conserved body plan, yet they employ a diverse array of locomotor modes, making them ideal organisms for investigating the relationships between morphology and locomotor function, in particular whether anatomical complexity is a prerequisite for functional complexity. We use diffusible iodine contrast-enhanced microCT (diceCT) imaging to digitally dissect the gross muscle anatomy of the pelvis and hindlimbs for 30 species of frogs representing five primary locomotor modes, including the first known detailed dissection for some of the world's smallest frogs, forming the largest digital comparative analysis of musculoskeletal structure in any vertebrate clade to date. By linking musculoskeletal dissections and phylogenetic comparative methods, we then quantify and compare relationships between anatomy and function across over 160 million years of anuran evolution. In summary, we have found that bone lengths and pelvic crest sizes are generally not reliable predictors of muscle sizes, which highlights important implications for future palaeontological studies. Our investigation also presents previously unreported differences in muscle anatomy between frogs specialising in different locomotor modes, including several of the smallest frog hindlimb muscles, which are extremely difficult to extract and measure using traditional approaches. Furthermore, we find evidence of many-to-one and one-to-many mapping of form to function across the phylogeny. Additionally, we perform the first quantitative analysis of how the degree of muscle separation can differ between frogs. We find evidence that phylogenetic history is the key contributing factor to muscle separation in the pelvis and thigh, while the separation of shank muscles is influenced more strongly by locomotor mode. Finally, our anatomical 3D reconstructions are published alongside this manuscript to contribute towards future research and serve as educational materials.

Anatomical and surgical considerations of the pectoralis muscle.

The pectoralis major (PM) muscle is the largest and most superior muscle of the anterior chest wall. The PM plays an important role in flexion, adduction, and internal rotation of the arm. The pectoralis major's size, strength, and anatomical location make it an excellent candidate in transfer surgeries due to its ability to restore balancing forces that may be lost in scapular winging and subscapularis tears. Each of these injuries and pathologies involves the PM muscle in some way, and careful consideration of its anatomy and physiology is necessary. This review article aims to provide a comprehensive overview of the anatomy, physiology, and surgical considerations of the pectoralis muscle with a specific focus on the surgical techniques involving the muscle. A comprehensive literature search using a combination of the following terms: pectoralis major, rupture, transfer, chronic subscapularis tear, pectoralis surgery, anatomy, scapular winging, and long thoracic nerve anatomy. There were no limitations with regards to article type or publishing date, but article language was limited to only English. The pectoralis muscle is an important muscle when it comes to function of the upper extremity primarily or through transfer procedure. Injuries and impairments of the pectoralis major or other muscles of the upper extremity can significantly impact an individual's quality of life, limiting their ability to perform activities of daily living. A thorough understanding of anatomical, functional, and surgical purposes of the pectoralis muscle is crucial for achieving optimal outcomes and avoiding complications.

Research on gravity compensation control of BPNN upper limb rehabilitation robot based on particle swarm optimization

AbstractA four‐degree‐of‐freedom upper limb exoskeleton rehabilitation robot system with a gravity compensation device is constructed. The objective is to address the rehabilitation training needs of patients with upper limb motor dysfunction. A BP neural network adaptive control method based on particle swarm optimization is proposed. First, the degrees of freedom of the human body are analyzed, and a Lagrange method is employed to construct a dynamic model. Second, a particle swarm optimization back propagation neural network adaptive control algorithm based on particle swarm optimization is presented. Subsequently, the range of motion of the upper limbs is analyzed with reference to muscle anatomy and a three‐dimensional motion capture system. And the robot structure design is analyzed in detail. Finally, simulation experiments were conducted, and the results demonstrated that the proposed method exhibited high effectiveness and accuracy.

Bee morphology: A skeletomuscular anatomy of Thyreus (Hymenoptera: Apidae).

Although the knowledge of the skeletal morphology of bees has progressed enormously, a corresponding advance has not happened for the muscular system. Most of the knowledge about bee musculature was generated over 50 years ago, well before the digital revolution for anatomical imaging, including the application of microcomputed tomography. This technique, in particular, has made it possible to dissect small insects digitally, document anatomy efficiently and in detail, and visualize these data three dimensionally. In this study, we document the skeletomuscular system of a cuckoo bee, Thyreus albomaculatus and, with that, we provide a 3D atlas of bee skeletomuscular anatomy. The results obtained for Thyreus are compared with representatives of two other bee families (Andrenidae and Halictidae), to evaluate the generality of our morphological conclusions. Besides documenting 199 specific muscles in terms of origin, insertion, and structure, we update the interpretation of complex homologies in the maxillolabial complex of bee mouthparts. We also clarify the complicated 3D structure of the cephalic endoskeleton, identifying the tentorial, hypostomal, and postgenal structures and their connecting regions. We describe the anatomy of the medial elevator muscles of the head, precisely identifying their origins and insertions as well as their homologs in other groups of Hymenoptera. We reject the hypothesis that the synapomorphic propodeal triangle of Apoidea is homologous with the metapostnotum, and instead recognize that this is a modification of the third phragma. We recognize two previously undocumented metasomal muscle groups in bees, clarifying the serial skeletomusculature of the metasoma and revealing shortcomings of Snodgrass' "internal-external" terminological system for the abdomen. Finally, we elucidate the muscular structure of the sting apparatus, resolving previously unclear interpretations. The work conducted herein not only provides new insights into bee morphology but also represents a source for future phenomic research on Hymenoptera.

Mechanisms for pelvic floor muscle training: Morphological changes and associations between changes in pelvic floor muscle variables and symptoms of female stress urinary incontinence and pelvic organ prolapse-A narrative review.

Today there is Level 1, recommendation A for pelvic floor muscle training (PFMT) to be effective in treatment of stress urinary incontinence (SUI) and pelvic organ prolapse (POP). However, the mechanisms of action are discussed. The aim of the present overview was to give an update of studies evaluating the effect of PFMT on pelvic floor morphology and associations between changes in PFM strength and symptoms of female SUI and POP. MATERIALS ANDMETHODS: This was a narrative review retrieving studies from systematic reviews of PFMT for SUI and POP. In addition, an open search on PubMed with the search terms PFMT and morphology was conducted. Both randomized controlled trials (RCTs) and pre-posttest design studies were included. PEDro rating scale (0-10) was used to assess risk of bias. Ten studies were found reporting on morphological changes after PFMT. The four RCTs had PEDro score between 5 and 8/10. The studies found significant higher bladder neck position and narrower levator hiatus dimensions, thicker external urethral sphincter, increased cross-sectional area of PFM, improvement in PFM tears and blood flow. Twenty studies analyzed associations between changes in different PFMT variables and SUI and POP. Eleven studies found a positive weak to moderate association and six studies reported no association. Studies comparing responders and nonresponders to PFMT found statistically significant better PFM variables in responders. PFMT can change pelvic floor muscle and external urethral sphincter anatomy. This contributes to the understanding on how PFMT can be effective in prevention and treatment of SUI and POP.

Newly revealed anatomy of the bucinator muscle: An anatomical and histological study

BackgroundCurrent anatomical knowledge of the origin of the bucinator muscle (BM), i.e., long thin attachments on the maxilla and mandible and the pterygomandibular raphe (PMR), is not supported by anatomical dissection of this muscle. The aim of this study was therefore to investigate the detailed morphology of the BM and associated structures and to discuss its function. MethodsThe anatomy of the BM and related structures was investigated in 15 cadaveric heads using a surgical microscope and histological analysis. ResultsThe inferior fibers of the BM originated from a small retromolar area (internal oblique line), which shared a common tendon with the deep tendon of the temporalis. The superior fibers of the BM originated from the maxillary tuberosity. The middle fibers originated the pterygoid hamulus. No PMR was identified in any of the specimens, but the border between the BM and superior pharyngeal constrictor muscle (SC) was clear because the muscle fibers followed different directions. Some horizontal fibers were continuous between the BM and SC. ConclusionsOur results suggest the need to revise established accounts of the origins of the bucinator (the maxillary tuberosity, conjoint tendon of the temporalis, and pterygoid hamulus without a pterygomandibular raphe. It also needs to be noted that some of its fibers merge directly with the SC.

Optimal Gearing of Musculoskeletal Systems.

Movement is integral to animal life, and most animal movement is actuated by the same engine: striated muscle. Muscle input is typically mediated by skeletal elements, resulting in musculoskeletal systems that are geared: at any instant, the muscle force and velocity are related to the output force and velocity only via a proportionality constant G, the "mechanical advantage". The functional analysis of such "simple machines" has traditionally centered around this instantaneous interpretation, such that a small vs large G is thought to reflect a fast vs forceful system, respectively. But evidence is mounting that a comprehensive analysis ought to also consider the mechanical energy output of a complete contraction. Here, we approach this task systematically, and deploy the theory of physiological similarity to study how gearing affects the flow of mechanical energy in a minimalist model of a musculoskeletal system. Gearing influences the flow of mechanical energy in two key ways: it can curtail muscle work output, because it determines the ratio between the characteristic muscle kinetic energy and work capacity; and it defines how each unit of muscle work is partitioned into different system energies, that is, into kinetic vs "parasitic" energy such as heat. As a consequence of both effects, delivering maximum work in minimum time and with maximum output speed generally requires a mechanical advantage of intermediate magnitude. This optimality condition can be expressed in terms of two dimensionless numbers that reflect the key geometric, physiological, and physical properties of the interrogated musculoskeletal system, and the environment in which the contraction takes place. Illustrative application to exemplar musculoskeletal systems predicts plausible mechanical advantages in disparate biomechanical scenarios, yields a speculative explanation for why gearing is typically used to attenuate the instantaneous force output ($G_{\text{opt}} \lt 1)$, and predicts how G needs to vary systematically with animal size to optimize the delivery of mechanical energy, in superficial agreement with empirical observations. A many-to-one mapping from musculoskeletal geometry to mechanical performance is identified, such that differences in G alone do not provide a reliable indicator for specialization for force vs speed-neither instantaneously, nor in terms of mechanical energy output. The energy framework presented here can be used to estimate an optimal mechanical advantage across variable muscle physiology, anatomy, mechanical environment, and animal size, and so facilitates investigation of the extent to which selection has made efficient use of gearing as a degree of freedom in musculoskeletal "design."

A dysphagia model with denervation of the pharyngeal constrictor muscles in guinea pigs: functional evaluation of swallowing.

Swallowing impairment is a crucial issue that can lead to aspiration, pneumonia, and malnutrition. Animal models are useful to reveal pathophysiology and to facilitate development of new treatments for dysphagia caused by many diseases. The present study aimed to develop a new dysphagia model with reduced pharyngeal constriction during pharyngeal swallowing. We analyzed the dynamics of pharyngeal swallowing over time with the pharyngeal branches of the vagus nerve (Ph-X) bilaterally or unilaterally transected, using videofluoroscopic assessment of swallowing in guinea pigs. We also evaluated the detailed anatomy of the pharyngeal constrictor muscles after the denervation. Videofluoroscopic examination of swallowing showed a significant increase in the pharyngeal area during swallowing after bilateral and unilateral sectioning of the Ph-X. The videofluoroscopy also showed significantly higher pharyngeal transit duration for bilateral and unilateral section groups. The thyropharyngeal muscle on the sectioned side was significantly thinner than that on the intact side. In contrast, the thickness of the cricopharyngeal muscles on the sectioned and intact sides were not significantly different. The mean thickness of the bilateral thyropharyngeal muscles showed a linear correlation to the pharyngeal area and pharyngeal transit duration. Data obtained in this study suggest that denervation of the Ph-X could influence the strength of pharyngeal contraction during pharyngeal swallowing in relation to thickness of the pharyngeal constrictor muscles, resulting in a decrease in bolus speed. This experimental model may provide essential information (1) for the development of treatments for pharyngeal dysphagia and (2) on the mechanisms related to the recovery process, reinnervation, and nerve regeneration following injury and swallowing impairment possibly caused by medullary stroke, neuromuscular disease, or surgical damage from head and neck cancer.

Modern methods for chest wall reconstruction using the pectoralis major muscle

The article discusses current trends in the use of the pectoralis major muscle in restorative operations for chest wall defects resulting from infectious and inflammatory processes. The scientific literature for analysis was found in the following databases: RSCI, PubMed, Web of Science. The mostly discussed topics are features of the anatomy and anomalies of the pectoralis major muscles, variants of pectoralis major flaps, the main nosologies requiring pectoralis major muscle plasty, complications after using the pectoralis major flaps.

The quadratus femoris muscle anatomy: Do we know everything?

IntroductionThe purpose of this study was to characterize the morphological variations in the quadratus femoris muscle (QF) and to create an anatomical classification that could be used in the planning of surgical procedures in this area, radiological imaging, and rehabilitation. Materials and methodsNinety-two lower limbs from 46 cadavers, fixed in 10 % formalin solution, were examined. ResultsThe QF muscle was present in all specimens. According to morphology, the QF muscle was classified into three types. The most common type was Type I, characterized by one muscular belly (78.3 %), while the second most common type was Type II, characterized by two bellies, was observed in 17.4 % of cases. The rarest type was Type III. It was characterized by three bellies and was found in 4.3 % of the cases. ConclusionsThe current classification system on quadratus femoris morphological variability is novel. Morphological variants may contribute to clinical issues, such as the ischiofemoral impingement syndrome, that could arise from type I quadratus femoris. Hence, the current study may be applicated to planning surgical procedures, imaging, and rehabilitation.

Clinical Implications of Fat Grafting in the Posterior Calf: A Dynamic Cadaver-based Study.

Intramuscular fat grafting in extremity muscles, especially the gastrocnemius, has become increasingly popular. However, while safety in truncal muscle fat grafting has been well-studied, research on extremity muscles is lacking. In this study, we aimed to explore the anatomy of the gastrocnemius muscle and adjacent structures as intramuscular and subcutaneous recipient sites. Additionally, we sought to analyze pressure-volume relationships and fat migration patterns during posterior calf grafting. Eight cadaveric lower extremities were examined. A prosection was performed to better understand the vascular complex around the gastrocnemius. Ultrasound-guided fat injections were then performed into both the subcutaneous and intramuscular layers; dynamic pressures were measured with a manometer. Last, dyed-injectant was injected subcutaneously to better elucidate subcutaneous anatomy. Anatomic prosection demonstrated the proximity of the gastrocnemius muscle to the popliteal venous system that arborized (>1 mm) intramuscularly. In the 3 specimens that underwent intramuscular fat grafting, the peak intramuscular pressures plateaued at 21 mmHg (19.5-23 mmHg); there was no observed extrafascial migration of the injectant. With subcutaneous injectant in 1 specimen, pressures in the subcutaneous space increased (125 mmHg) with additional injectant (240 mL) while pressures in the intramuscular space remained relatively constant (4 mmHg). Intramuscular gastrocnemius fat grafting should be done with caution: its proximity to critical veins and sustained increased intramuscular pressures following grafting increases risks of embolus and thrombosis, respectively. Subcutaneous injection may be safer in that increased pressures are not communicated to deep structures. Last, we present a novel description of posterior calf subcutaneous compartments that may better allow surgeons to direct and predict subcutaneous injectant.

경도 및 중등도 안면마비환자를 위한 셀프 스트레칭 치료의 의의

Background: It is necessary for facial palsy patients to be educated and proceed consistently with self-stretching exercise considering facial muscular anatomy to maximize the effect of self-educated facial stretching exercise. But there are few references for the patients to specifically learn any methodological techniques that can be implemented in detail. It is aimed to demonstrate the effective and consistent home-educational stretching exercise for facial paralysis patients considering the anatomical features of facial muscles to provide easily-accessible technical methods. Materials and Methods: For the self-muscular stretching exercise, it is necessary to first learn the anatomical position and contraction direction of the muscles that basically form the facial part because the specific method differs according to the characteristics of each facial muscle. The basic technique consists of firm but gentle stretching of each affected muscle group in the opposite direction from which it contracts that can be combated by regular stretches and gentle isotonic exercises. Results: It is expected that patients suffering from facial paralysis can enjoy a better quality of life if they can use the facial exercise method that can be performed independently without anyone’s help in consideration of the direction of the facial anatomical muscles. Conclusions: This study is a method devised to minimize facial contracture by facial palsy in consideration of the anatomical characteristics of facial muscles in order to educate patients and facilitate home training in case of facial palsy.