Soft Tissue Anatomy Research Articles

Digital 3D facial approximation of the Petralona skull. Methodological issues and applications

The human face is a highly specialized anatomical entity. Its appearance is a result of evolutionary processes that include biomechanical, physiological, and social influences. The facial approximation is based on the relevance of skeletal and soft tissue anatomy and aims to reconstruct a person's face from the anatomical features of the skull. In forensics, the technique focuses on the estimation of the facial characteristics of unidentified individuals. In archaeological contexts, it has been widely used for the representation of hominins, prehistoric and historic periods individuals. For the facial approximation of the Petralona man, we digitized a cast of the original skull with an Artec Spider 3D scanner of metrological accuracy up to 0.05mm. A digital model of the Mauer mandible (Germany), the holotype of Homo heidelbergensis, was used to virtually complement the skeletal anatomy of the face. Cinema4D (Maxon) was used to place soft tissue depth markers according to standard nomenclature. The digital reconstruction of facial anatomy and skin texture was developed in ZBrush (Pixologic). The facial features were approximated with the use of techniques that are based on anatomical and/or statistical evidence. The facial approximation of the Petralona skull aims to disseminate scientific information and contribute to the public understanding of evolutionary science.

A novel approach for quantitative imaging of the seated anatomy of the buttocks using ultrasound and MRI

Background: Pressure injuries are commonly noted in individuals who use wheelchairs for mobility and sit for prolonged periods. Understanding soft tissue composition is an essential part of treating and preventing pressure injuries. This study proposes novel approaches for imaging the soft tissue of the buttocks in unloaded and loaded conditions using ultrasound (US) and magnetic resonance imaging (MRI).Methods: The soft tissue of the buttocks was measured in able-bodied participants (n = 26, 50% female) and one male with a spinal cord injury using an innovative chair that allowed seated US acquisition of the buttocks and a newly developed MRI compatible loader. The US test–retest reliability (reproducibility) of buttocks soft tissue was assessed, and US was validated with MRI. Soft tissue was measured between the peak of the ischial tuberosity (IT) and proximal femur and the skin. MRI was used to quantify the fat fraction of the gluteus maximus muscle, with the goal of determining the influence of intramuscular fat on loaded soft tissue responses and was used to assess tissue thickness during buttocks loading.Results: US reproducibility was excellent, ICC = 0.934–0.981, with no statistical differences between scan days. Coefficients of variation (CVs) between visits ranged from 2.5% to 7.4% for loaded and unloaded tissue. US and MRI measures of tissue thickness were significantly correlated (r = 0.68–0.91, p ≤ 0.001). US underestimated the unloaded tissue thicknesses, with a mean bias of 0.39–0.56 cm. When the buttocks were loaded, US- and MRI-measured total tissue thickness was reduced by up to 64.2% ± 9.1% (p < 0.001). The US- and MRI-unloaded total soft tissue of the IT was correlated with loaded tissue thickness (r = 0.54–0.67, p ≤ 0.027). Intramuscular fat of the gluteus maximus was not correlated to changes in muscle thickness with loading (r = 0.05, p > 0.05).Conclusion: We have developed and validated a novel US methodology using MRI as a comparison measure to investigate soft tissue anatomy and deformation during sitting and loading. The ability to obtain such data in the loaded condition is unique and fills an unmet need in understanding loading and pressure injury formation.

Cadaveric Biomechanical Study of Partial Glenoid Arthroplasty Versus the Latarjet Procedure for Anterior Glenoid Bone Loss

Background: For severe anterior glenoid bone loss due to recurrent shoulder instability, the Latarjet procedure offers a dynamic sling effect in addition to bone augmentation. Yet, it heavily alters the surrounding anatomy, while fixation and graft union issues are also common. Purpose/Hypothesis: The purpose of this study was to compare a novel printed 3-dimensional (3D) partial glenoid arthroplasty (PGA) implant with the classic Latarjet procedure. It was hypothesized that by replicating the original glenoid geometry and preserving soft tissue anatomy, PGA may better reproduce normal joint kinematics. In addition, the locking screw construct may offer stronger fixation. Study Design: Controlled laboratory study. Methods: A total of 14 matched cadaveric shoulders were tested. The PGA implant was 3D printed in titanium based on preoperative computed tomography. The intact, 25% anterior glenoid bone loss, and postoperative states were tested in the scapular and coronal planes. The following parameters were measured: articular surface area and stepoff, rotational range of motion and the humeral head apex position during rotation, and load and linear stiffness at 25% anterior translation and at 2-mm construct displacement. Results: The baseline dimensions of the glenoid articular surface were comparable between the groups. The articular surface area after PGA was significantly larger (P = .006) with less articular stepoff (P = .030). PGA better approximated the intact state’s external (P = .006) and total (P = .019) rotational range of motion in the scapular plane. The course of the humeral head apex after PGA better followed that of the intact state (P < .001). Resistance against anterior translation after PGA was not significantly different compared with after the Latarjet procedure. Greater linear stiffness (P = .031) and loading (P = .002) at 2-mm construct displacement were demonstrated in the PGA group. Conclusion: In addressing anterior glenoid bone loss, PGA better approximated intact glenohumeral joint kinematics compared with the Latarjet procedure with less articular stepoff in a cadaveric model. PGA was comparable in resisting anterior translation while being significantly stronger against loading at 2-mm construct displacement. Further clinical studies are warranted to validate this novel procedure. Clinical Relevance: A 3D-printed PGA implant may offer an alternative treatment option for severe glenoid bone loss due to shoulder instability, overcoming the previous drawbacks of the Latarjet procedure, including altered kinematics, fixation failure, and hardware issues.

Beyond the Malleoli: Part 2—Avulsion Fractures of the Hindfoot

Avulsion fractures of the ankle and hindfoot are a diverse group of injuries occurring at level of retinacular, capsuloligamentous, and tendinous attachments. Accurate identification of avulsion fractures and their origins is based on understanding the relevant soft-tissue anatomy. In the first part of this two-series article, avulsion fractures at level of the ankle retinacula and distal tibiofibular syndesmosis were reviewed. The second part of this series of two articles is dedicated to reviewing the relevant anatomy, injury mechanisms, classification, nomenclature, imaging, treatment, and complications of hindfoot avulsion fractures occurring at level of the lateral ankle ligament complex (distally), posterior talar process, tendinous attachments, and miscellaneous soft-tissue attachments not otherwise specified.

Management of Oral Thrush in an Infant with Cleft Lip and Palate (A Case Report)

Oral candidiasis is the most common human fungal infection seen with a wide range of carrier rates ranging from 2% to as high as 95% among various age groups, especially in children and the elderly, often found in immunocompromised individuals but can also occur in healthy individuals. Although considered a pathogen, Candida albicans is a commensal organism that usually colonizes the oral mucosa and is isolated in the oral cavity of healthy individuals. Several risk factors for oral candidiasis in cleft lip and palate patients include changes in oral microflora, variations in hard and soft tissue anatomy, immunocompromised state, and high number of frequent hospitalizations. Candida albicans adhering to the oral cavity can be a cause of infection, however, removal of adherent candida cells from the mucosal surface through the effects of salivary flow and swallowing is the most important factor in preventing candida overgrowth. The aim of this paper is to evaluate the management of oral thrush in infant with cleft lip and palate.

Periodontal regeneration risk assessment in the treatment of intrabony defects.

Regenerative approaches performed in periodontics seems to be efficient in treating intrabony defects. There are, however, many factors that may affect the predictability of the regenerative procedures. The present article aimed to propose a new risk assessment tool for treating periodontal intrabony defects by regenerative therapy. Different variables that could affect the success of a regenerative procedure were considered based on their impact on (i) the wound healing potential, promoting wound stability, cells, and angiogenesis, or (ii) the ability to clean the root surface and maintain an optimal plaque control or (iii) aesthetics (risk for gingival recession). The risk assessment variables were divided into a patient, tooth, defect, and operator level. Patient-related factors included medical conditions such as diabetes, smoking habit, plaque control, compliance with supportive care, and expectations. Tooth-related factors included prognosis, traumatic occlusal forces or mobility, endodontic status, root surface topography, soft tissue anatomy, and gingival phenotype. Defect-associated factors included local anatomy (number of residual bone walls, width, and depth), furcation involvement, cleansability, and number of sides of the root involved. Operator-related factors should not be neglected and included the clinician's level of experience, the presence of environmental stress factors, and the use of checklists in the daily routine. Using a risk assessment comprised of patient-, tooth-, defect- and operator-level factors can aid the clinician in identifying challenging characteristics and in the treatment decision process.

Craniofacial Soft-Tissue Anthropomorphic Database with Magnetic Resonance Imaging and Unbiased Diffeomorphic Registration.

Objective assessment of craniofacial surgery outcomes in a pediatric population is challenging because of the complexity of patient presentations, diversity of procedures performed, and rapid craniofacial growth. There is a paucity of robust methods to quantify anatomical measurements by age and objectively compare craniofacial dysmorphology and postoperative outcomes. Here, the authors present data in developing a racially and ethnically sensitive anthropomorphic database, providing plastic and craniofacial surgeons with "normal" three-dimensional anatomical parameters with which to appraise and optimize aesthetic and reconstructive outcomes. Patients with normal craniofacial anatomy undergoing head magnetic resonance imaging (MRI) scans from 2008 to 2021 were included in this retrospective study. Images were used to construct composite (template) images with diffeomorphic image registration method using the Advanced Normalization Tools package. Composites were thresholded to generate binary three-dimensional segmentations used for anatomical measurements in Materalise Mimics. High-resolution MRI scans from 130 patients generated 12 composites from an average of 10 MRI sequences each: four 3-year-olds, four 4-year-olds, and four 5-year-olds (two male, two female, two Black, and two White). The average head circumference of 3-, 4-, and 5-year-old composites was 50.3, 51.5, and 51.7 cm, respectively, comparable to normative data published by the World Health Organization. Application of diffeomorphic registration-based image template algorithm to MRI is effective in creating composite templates to represent "normal" three-dimensional craniofacial and soft-tissue anatomy. Future research will focus on development of automated computational tools to characterize anatomical normality, generation of indices to grade preoperative severity, and quantification of postoperative results to reduce subjectivity bias.

Personalized statistical modeling of soft tissue structures in the knee.

Background and Objective: As in vivo measurements of knee joint contact forces remain challenging, computational musculoskeletal modeling has been popularized as an encouraging solution for non-invasive estimation of joint mechanical loading. Computational musculoskeletal modeling typically relies on laborious manual segmentation as it requires reliable osseous and soft tissue geometry. To improve on feasibility and accuracy of patient-specific geometry predictions, a generic computational approach that can easily be scaled, morphed and fitted to patient-specific knee joint anatomy is presented. Methods: A personalized prediction algorithm was established to derive soft tissue geometry of the knee, originating solely from skeletal anatomy. Based on a MRI dataset (n = 53), manual identification of soft-tissue anatomy and landmarks served as input for our model by use of geometric morphometrics. Topographic distance maps were generated for cartilage thickness predictions. Meniscal modeling relied on wrapping a triangular geometry with varying height and width from the anterior to the posterior root. Elastic mesh wrapping was applied for ligamentous and patellar tendon path modeling. Leave-one-out validation experiments were conducted for accuracy assessment. Results: The Root Mean Square Error (RMSE) for the cartilage layers of the medial tibial plateau, the lateral tibial plateau, the femur and the patella equaled respectively 0.32mm (range 0.14-0.48), 0.35mm (range 0.16-0.53), 0.39mm (range 0.15-0.80) and 0.75mm (range 0.16-1.11). Similarly, the RMSE equaled respectively 1.16mm (range 0.99-1.59), 0.91mm (0.75-1.33), 2.93mm (range 1.85-4.66) and 2.04mm (1.88-3.29), calculated over the course of the anterior cruciate ligament, posterior cruciate ligament, the medial and the lateral meniscus. Conclusion: A methodological workflow is presented for patient-specific, morphological knee joint modeling that avoids laborious segmentation. By allowing to accurately predict personalized geometry this method has the potential for generating large (virtual) sample sizes applicable for biomechanical research and improving personalized, computer-assisted medicine.

Architecture of head and neck soft tissues and associated entheses: An exploration of sexual dimorphism in, and population differences between, New Zealand and Thai individuals.

Understanding the musculoskeletal anatomy of soft tissues of the head and neck is important for surgical applications, biomechanical modelling and management of injuries, such as whiplash. Additionally, analysing sex and population differences in cervical anatomy can inform how biological sex and population variation may impact these anatomical applications. Although some muscles of the head and neck are well-studied, there is limited architectural information thatalso analyses sex and population variation, for many small cervical soft tissues (muscles and ligaments) and associated entheses (soft tissue attachment sites). Therefore, the aim of this study was to present architectural data (e.g., proximal and distal attachment sites, muscle physiological cross-sectional area, ligament mass, enthesis area) and analyse sex and population differences in soft tissues and entheses associated with sexually dimorphic landmarks on the cranium (nuchal crest and mastoid process) and clavicle (rhomboid fossa). Through the dissection and three-dimensional analysis of 20 donated cadavers from New Zealand (five males, five females; mean age 83 ± 8 years; range 67-93 years) and Thailand (five males, five females; 69 ± 13 years; range 44-87 years), the following soft tissues and their associated entheses were analysed: upper trapezius, semispinalis capitis and the nuchal ligament (nuchal crest); sternocleidomastoid, splenius capitis and longissimus capitis (mastoid process); the clavicular head of pectoralis major, subclavius, sternohyoid and the costoclavicular (rhomboid) ligament (rhomboid fossa). Findings indicate that although muscle, ligament and enthesis sizes were generally similar to previously published data, muscle size was smaller for six of the eight muscles in this study, with only the upper trapezius and subclavius demonstrating similar values to previous studies. Proximal and distal attachment sites were largely consistent with the current research. However, some individuals (six of 20) had proximal upper trapezius attachments on the cranium, with most attaching solely to the nuchal ligament, contrasting with existing literature, which often describes attachment to the occipital bone. With respect to sexual dimorphism, the Thai sample exhibited more sex differences in muscle size than the New Zealand sample, but for enthesis size (area), both samples had the same amount of statistically significant sex differences (5 of 10). Additionally, some significant population differences were found when comparing muscle and enthesis size data between the New Zealand and Thai samples. Despite these findings, no sex or population differences were found for ligament size (mass) in either group. This paper presents new architectural data for several understudied areas of the head and neck, as well as providing analyses on sex and population differences, two areas that have limited representation in anatomy.

Proximal Anterolateral Accessory Portal Use Improves Peripheral Compartment Access and Capsular Management with T-Capsulotomy

One of the primary goals of hip arthroscopy for femoroacetabular impingement (FAI) syndrome is precise removal of pathologic FAI morphology while protecting and restoring the normal soft tissue anatomy. Adequate visualization is a key foundation of precise removal of FAI morphology and varying types of capsulotomies are frequently used to achieve necessary exposure. Anatomic and outcomes studies have influenced an increasing appreciation for repairing these capsulotomies. Thus one of the central technical challenges of hip arthroscopy is achieving both goals of capsule preservation and adequate visualization. Various techniques have been described, including suture-based capsule suspension, portal placement, and T-capsulotomy. The following technique describes how the proximal anterolateral accessory portal can be added to a capsule suspension and T-capsulotomy technique to improve visualization and facilitate repair.

Superimposition of intraoral scans of an edentulous arch with implants and implant-supported provisional restoration, implementing a novel implant prosthetic scan body.

Purpose To describe a technique utilizing a novel prosthetic scan body, that assists the accurate merging of multiple scans (intra- and extraoral) of the interim prosthesis and edentulous arch with dental implants, during rehabilitation with a fixed implant-supported prosthesis.Methods Intraoral scanning (Trios 3, 3Shape) of an interim implant-supported prosthesis was performed, subsequently followed by another scan, using five scan bodies, placed onto the implant abutments (SRA, Bone level, Straumann AG). Successively, the newly designed prosthetic scan bodies were attached to the abutment copings of the interim prosthesis, for extraoral scanning. Utilizing an implant library designed for the prosthetic scan body, the three scans were merged, providing all the necessary information for the digital design and fabrication of the fixed implant-supported prosthesis.Conclusions The described clinical technique enabled effective and accurate superimposition of intra- and extraoral scans of the implant prosthesis. Superimposed data, including that of the position of dental implants and anatomy of soft tissue, provided essential information for the fabrication of a definitive implant-supported prosthesis. The novel prosthetic scan bodies attached to the implant prosthesis, assisted in merging intra- and extraoral scans, thus facilitating the rehabilitation of maxillary and/or mandibular edentulous dental arches. Further research is required to assess the accuracy of the proposed technique.

Acetabular labrum and cartilage contact mechanics during pivoting and walking tasks in individuals with cam femoroacetabular impingement syndrome

Femoroacetabular impingement syndrome (FAIS) is a motion-related pathology of the hip characterized by pain, morphological abnormalities of the proximal femur, and an elevated risk of joint deterioration and hip osteoarthritis. Activities that require deep flexion are understood to induce impingement in cam FAIS patients, however, less demanding activities such as walking and pivoting may induce pain as well as alterations in kinematics and joint stability. Still, the paucity of quantitative descriptions of cam FAIS has hindered understanding underlying hip joint mechanics during such activities. Previous in silico studies have employed generalized model geometry or kinematics to simulate impingement between the femur and acetabulum, which may not accurately capture the interplay between morphology and motion. In this study, we utilized models with participant-specific bone and articular soft tissue anatomy and kinematics measured by dual-fluoroscopy to compare hip contact mechanics of cam FAIS patients to controls during four activities of daily living (internal/external pivoting and level/incline walking). Averaged across the gait cycle during incline walking, patients displayed increased strain in the anterior joint (labrum strain: p-value = 0.038, patients: 11.7 ± 6.7 %, controls: 5.0 ± 3.6 %; cartilage strain: p-value = 0.029, patients: 9.1 ± 3.3 %, controls: 4.2 ± 2.3). Patients also exhibited increased average anterior cartilage strains during external pivoting (p-value = 0.039; patients: 13.0 ± 9.2 %, controls: 3.9 ± 3.2 %]). No significant differences between patient and control contact area and strain were found for level walking and internal pivoting. Our study provides new insights into the biomechanics of cam FAIS, including spatiotemporal hip joint contact mechanics during activities of daily living.

Soft tissue stabilization of the hinge position in medial closed wedge distal femoral osteotomy: an anatomical study

BackgroundSoft tissue has an important role in stabilizing the hinge point of medial closed wedge distal femoral osteotomy (MCWDFO). However, there are conflicting data on the soft tissue anatomy around the hinge point of MCWDFO and, therefore, further anatomical data are needed. The purposes of the study were to: 1) anatomically analyze the soft tissue around the hinge point of MCWDFO; 2) radiologically define the appropriate hinge point to prevent an unstable hinge fracture based on the result of the anatomical analysis; and 3) histologically analyze the soft tissue based on the result of the anatomical analysis.MethodsIn 20 cadaveric knees, the capsule attachment of the distal lateral side of the femur was marked with a radiopaque ball bearing. A digital planning tool was used to calculate the area of the marked capsule attachment around the ideal hinge point of MCWDFO on radiographs. The soft tissue around the hinge point was histologically examined and the periosteal thickness was measured and visualized graphically. The graph and radiograph were overlayed using image editing software, and the appropriate hinge position was determined based on the periosteal thickness.ResultsAs a result, the periosteal thickness of the distal lateral femur tended to rapidly decrease from the metaphyseal region toward the diaphyseal region. The overlayed graph and radiograph revealed that the periosteal thickness changed in the region corresponding to the apex of the turning point of the femoral metaphysis in all cases.ConclusionsIn conclusion, the periosteum might support the hinge of MCWDFO within the area surrounded by the apex of the turning point of the femoral metaphysis and the upper border of the posterior part of the lateral femoral condyle.

Orbital soft tissues, bones, and allometry: Implications for the size and position of crocodylian eyes.

Although the visual system of crocodylians has attracted interest regarding optical parameters and retinal anatomy, fundamental questions remain about the allometry of the eyeball and whether such scaling is the same across all crown groups of crocodylians. In addition, anatomy and identities of adnexal soft tissues that interact with the visual system are not well understood in many cases. We used contrast-enhancing iodine stain and high-resolution micro-computed tomography to assess the anatomy of orbital soft tissues, including extraocular muscles and glands, in crocodylians. We also used regression analysis to estimate the allometric relationship between the bony orbit and eyeball across Alligator mississippiensis and Crocodylus niloticus for the first time. Results revealed tight, negatively allometric relationships between the bony orbit and eyeball. Notably, the eyes of C. niloticus were larger for a given orbit size than the eyes of A. mississippiensis, although the slope of the relationship was no different between these two crown crocodylian groups. Among the findings from our anatomical study, new details were uncovered about the homologies of muscles of the abducens complex. In particular, M. rectus lateralis of crocodylians is revealed to have a more complex form than previously appreciated, being adhered to the tendon of the nictitating membrane, which may be apomorphic for Crocodylia. Our calculation of the orbit-eyeball allometric relationship and study of the adnexal soft tissues of the crocodylian visual system, in combination with previous work by other teams in other crown saurian clades, is a critical, formerly missing, piece in the Extant Phylogenetic Bracket for restoring the visual apparatus of extinct crocodyliforms and other archosauriform groups.

Biomechanical analysis of pelvic holding pathways and strategies for use of the steinmann pin in pelvic fracture reduction

Pelvic fracture is the most serious bone trauma and has the highest mortality and disability rate. Surgical treatment of pelvic fracture is very challenging for surgeons. Minimally invasive close reduction of pelvic fracture is considered the most difficult operation due to the complex pelvic morphology and abundant soft tissue anatomy, both of which increase the difficulty of pelvic fracture reduction. The most challenging aspect of such surgery is how to hold the pelvic bone and effectively transmit the reduction force to the bone. Therefore, a safe and effective pelvic holding pathway for reduction is necessary for pelvic fracture operations. Existing research on the pelvic holding pathway addresses anatomical position and dimension. Few studies have focused on biomechanical properties or on surgical techniques related to these pathways. This paper studies the three holding pathways that are most commonly used in clinical practice. The most effective force direction for each holding pathway is identified through finite element modeling. Pathway 1 is suitable for internal rotation operation and open/close-book operation of the pelvis; Pathway 2 is suitable for translation of the fractured pelvis toward the sacrum and internal pelvic rotation operations; Pathway 3 is suitable for pulling and lifting of the fractured pelvis against gravity and open/close-book operation of the pelvis. In addition, we find through our simulation that the use of a combined holding strategy can reduce the reduction force during the reduction process. We compared the performances of the 2-pin combined holding strategy (2P–CH) and the 3-pin combined strategy (3P–CH). During translational reduction, 2P–CH and 3P–CH showed little difference in pelvic reduction force. However, in rotational reduction, 3P–CH shows advantages. It has less reduction force and the least combined muscle resistance. It can also maximize the displacement of the iliac crest under the same conditions. The results of this study can be applied to surgical planning and to the development of robot-assisted surgery systems in selecting holding pathways and operation strategies for fractured pelvis.

Internal anatomy of a fossilized embryonic stage ofthe Cambrian-Ordovician scalidophoran Markuelia.

The Wangcun fossil Lagerstätte in Hunan, South China, has yielded hundreds of fossilized embryos of Markuelia hunanensis representing different developmental stages. Internal tissues have only rarely been observed, impeding further understanding of the soft tissue anatomy, phylogenetic affinity and evolutionary significance of Markuelia. In this study, we used synchrotron radiation X-ray tomographic microscopy (SRXTM) to study a new collection of fossil embryos from the Wangcun fossil Lagerstätte. We describe specimens exhibiting a spectrum of preservation states, the best of which preserves palisade structures underneath the cuticle of the head and tail, distinct from patterns of centripetal mineralization of the cuticle and centrifugal mineralization of hypha-like structures, seen elsewhere in this specimen and other fossils within the same assemblage. Our computed tomographic reconstruction of these mineralization phases preserves the gross morphology of (i) longitudinal structures associated with the tail spines, which we interpret as the proximal ends of longitudinal muscles, and (ii) a ring-shaped structure internal to the introvert, which we interpret as a ring-shaped brain, as anticipated of the cycloneuralian affinity of Markuelia. This is the first record of a fossilized nervous system in a scalidophoran, and the first instance in Orsten-style preservation, opening the potential for further such records within this widespread mode of high-fidelity three-dimensional preservation.

Kembawacela yajuwayeyi n. sp., a new cistecephalid species (Dicynodontia: Emydopoidea) from the Upper Permian of Malawi

Cistecephalidae are a relatively basal clade of dicynodonts, well-nested within emydopoids, and known to have multiple adaptations to a fossorial lifestyle. In recent years cistecephalid taxonomic diversity has been progressively increasing and important insights into the osteology, soft-tissue anatomy, and paleobiology of the clade have improved considerably. Here we describe a new species of the cistecephalid Kembawacela from the Chiweta Beds (northern Malawi, Wuchiapingian), a poorly sampled area of Karoo sediments. Due to the minute dimensions and delicate nature of specimen DMMM-PK-16-1, we utilized propagation phase-contrast synchrotron X-ray micro-computed tomography, revealing conspicuous contrast between rock matrix and bone and allowing reconstruction of its cranial osteology in great detail. DMMM-PK-16-1 is here recognized as a new species based on the morphology of the crista oesophagea of the pterygoid, which has an acute posterior process separate from its contralateral. Despite the affinities with Kembawacela kitchingi there are various distinguishable features absent in the taxon (e.g., posterior border of the pterygoids is smoothly concave, rather than interdigitating with the basipostsphenoid). The erection of a new species in this region seems to support the growing evidence for species-level diversity in East African Karoo basins when contrasted to the Main South African Karoo basin. Furthermore, the anatomical resolution obtained allowed us to reconstruct the osseous labyrinth, the paths for several nerve branches, arteries and veins for the first time in cistecephalids, and we develop new hypotheses for their paths and nomenclature for dicynodonts. We found remarkable resemblance in the brain endocast of DMMM-PK-16-1 and another cistecephalid, Kawingasaurus, which is distinct from other dicynodonts in which it is known.

Editorial: Tetrapod water-land transition: Reconstructing soft tissue anatomy and function

Editorial: Tetrapod water-land transition: Reconstructing soft tissue anatomy and function

New frontiers in imaging, anatomy, and mechanics of crocodylian jaw muscles.

New imaging and biomechanical approaches have heralded a renaissance in our understanding of crocodylian anatomy. Here, we review a series of approaches in the preparation, imaging, and functional analysis of the jaw muscles of crocodylians. Iodine-contrast microCT approaches are enabling new insights into the anatomy of muscles, nerves, and other soft tissues of embryonic as well as adult specimens of alligators. These imaging data and other muscle modeling methods offer increased accuracy of muscle sizes and attachments without destructive methods like dissection. 3D modeling approaches and imaging data together now enable us to see and reconstruct 3D muscle architecture which then allows us to estimate 3D muscle resultants, but also measurements of pennation in ways not seen before. These methods have already revealed new information on the ontogeny, diversity, and function of jaw muscles and the heads of alligators and other crocodylians. Such approaches will lead to enhanced and accurate analyses of form, function, and evolution of crocodylians, their fossil ancestors and vertebrates in general.

Applied anatomy of the layers and soft tissues of the forehead during minimally-invasive aesthetic procedures.

An increasing demand of minimally-invasive aesthetic procedures of the forehead concomitantly leads to higher numbers of adverse events. Adequate application of anatomical knowledge is required to increase safety and efficacy of different minimally-invasive aesthetic procedures in this anatomical region. To describe the layered anatomy of the forehead soft tissues with respect to their thicknesses and how they relate to different minimally-invasive aesthetic treatments. A total of n=85 healthy study participants (69 females and 16 males) with a mean age of 40.84 ± 10.9 years and a mean body mass index of 22.65 ± 2.6kg/m2 were investigated with ultrasound-based imaging to measure the thickness of different forehead soft tissues. The mean overall soft tissue thickness of the forehead was measured to be 4.18 ± 0.7 mm for the entire study population. Increasing BMI values correlated statistically significantly with increasing thickness of all measured forehead soft tissues with exception of the frontalis muscle. On a statistically significant level, males showed thicker forehead soft tissues than females, with exception of the retrofrontalis fat and the frontalis muscle. On basis of the findings obtained in this study, basic treatment principles can be derived and improved for the injection of neuromodulators, hyaluronic acid as well as the application of polydiaxonane (PDO) threads and micro-focused ultrasound. Precise knowledge and thorough understanding of the layers and soft tissues of the forehead is required to guarantee safe and effective procedures in this aesthetically important facial region.