Insertion Of Muscle Research Articles

Cervicalgia and anomalous insertion of the levator scapulae muscle. Case report

Cervicalgia and anomalous insertion of the levator scapulae muscle. Case report

On the systematic position of the genus Fractonotus (Eutardigrada, Parachela)

The genus Fractonotus was erected on the basis of the peculiar appearance of the apophyses for the insertion of the stylet muscles on the buccal tube, and it has been attributed, together with the genus Microhypsibius, to the family Microhypsibiidae on the basis of the structure of the claws. A subsequent molecular investigation on Microhypsibius (18S and 28S rRNA) assigned the family Microhypsibiidae to the superfamily Hypsibioidea. Recently two other species, Isohypsibius gilvus and Calohypsibius verrucosus were transferred to Fractonotus and the latter was sequenced (18S and 28S rDNA, ITS-2), with the conclusion that the genus Fractonotus should be assigned to the family Isohypsibiidae, superfamily Isohypsibioidea. However, the transfer of I. gilvus and C. verrucosus to Fractonotus was incorrect. In fact, these two species definitely have claws of the Isohypsibius type, while Fractonotus caelatus, the type species of the genus, clearly has claws of the Microhypsibius type, in addition to other characters of the Hypsibioidea. Therefore, Fractonotus remains a monospecific genus in the Microhypsibiidae family, superfamily Hypsibioidea. The other two species belong to Isohypsibius or, if later confirmed by further morphological and new molecular data, to a new genus of Isohypsibiidae.

The importance of anatomical knowledge and execution technique for optimizing strength training results: opinion article

Strength training is essential for maintaining and optimizing health and is an effective non-pharmacological resource in the treatment of various comorbidities. The repercussions revolve around the promotion of motivated adaptations due to the planning and structuring of the training program through the manipulation of variables such as intensity, volume, selection and order of exercises, weekly frequency, cadence, and amplitude. These include the manipulation of variables such as intensity, volume, exercise selection and order, recovery interval, weekly frequency, cadence, and amplitude. This study aims to discuss the importance of anatomical knowledge and the use of an appropriate execution technique, which must be applied in strength exercises. However, what can be observed in practice is a lack of methodology, as well as an undefined movement standard of exercises, which is based on the premise of improving body composition. In this context, the study points to the need for a more robust discussion on the movement standard and the application of an adequate execution technique in three exercises commonly prescribed in physical training programs. Implementing a proper execution technique based on origin, muscle and joint insertion and actions could optimize strength, hypertrophy, and weight loss results. And, since improving these components is related to a reduction in comorbidities, there is a need for studies that discuss the role of movement execution in greater depth. Thus, further research could evoke a debate on the feasibility of incorporating execution technique as the eighth variable in muscle strength training. Keywords: Physical exercise; physical training; body composition.

Management of traumatic incomplete lacerating rectus muscle injuries using multimodal imaging approach (ASOCT and CT/MRI)

ABSTRACT Purpose: To describe the pathophysiology, importance of multimodal imaging approach, and the clinical outcomes of incomplete lacerating rectus muscle injuries. Methods: A retrospective review was conducted to identify patients with ocular deviation secondary to rectus muscle injuries. Between 2019 and 2022, a total of 30 patients were identified, amongst whom eleven patients had incompletely lacerated rectus muscles (secondary to penetrating adnexal trauma and sino-orbital surgeries). Patients’ demography, nature of injury, computed tomography/magnetic resonance imaging, anterior segment optical coherence tomography features, intra-operative findings, and post-operative outcomes were reviewed. Results: The mean age of 11 patients was 31.36 ± 14.38 years. All patients had external trauma which severed the muscle in its anterior portion. Five patients had isolated inferior rectus muscle injury (45.45%), three had inferior and medial rectus muscle injuries together (27.27%), two had isolated lateral rectus muscle injury (18.18%), and one remaining patient had isolated medial rectus muscle injury (9.05%). In ten patients (90.90%) CT/MRI revealed features suggestive of muscle injury, however details with respect to muscle insertion and scleral course were lacking. In this difficult scenario, ASOCT filled these lacunae in nearly 90% of the patients by providing surgically useful details. Moreover, when CT/MRI-ASOCT imaging features were combined, the management and outcomes were even more predictable. Conclusions: Penetrating rectus muscle injuries can be better identified as incompletely lacerated muscle using multimodal imaging approach. This simple image correlation process customizes the treatment approach and hence the clinical outcomes.

Cranial musculature of batoids: A standardized nomenclature.

Batoids (rays and skates) are cartilaginous fishes whose jaws are not articulated directly to the neurocranium. The only point of contact between them are the hyomandibular cartilages, resulting in a unique mandibular suspension called euhyostyly. Due to this decoupling of the jaws from the skull, muscles play an essential role in modulating mandibular movements during the feeding process, especially during mandibular protrusion. The main objectives of our study were: (1) to examine the mandibular musculature of eight batoid species from different orders in the Batoidea and (2) establish a standardized musclulature terminology for future comparative myological studies in batoids. For each muscle bundle, the general characteristics of each cranial muscle were described and their origin and insertions were identified. The number of muscle bundles differed intraspecifically. On the dorsal surface, we reported the first evidence of the presence of the precranial muscle (PCM) in U. halleri, as well as the ethmoideo-parethmoidalis muscle (ETM) in R. velezi, P. glaugostigma and Z. exasperata; in addition, the insertion of the spiracularis muscle (SP) extended to the ventral surface of the oropharyngeal tract in myliobatiforms. On the ventral surface of the head, both N. entemedor and M. californica exhibited additional muscles in the mandibular area. These muscles were renamed as part of the standardization of mandibular terminology: the depressor mandibularis minor (DMM) in N. entemedor and the adductor mandibulae profundus (AMP) in M. californica. The standardization of terminology is essential for futures studies of the mandibular apparatus in batoids, to facilitate the morphological description of muscles in species without anatomical accounts and for continuity in broader comparative analyses.

Accuracy of Boltless Frame-Based Stereo-Electroencephalography Electrode Implantation.

Boltless implantation of stereo-electroencephalography electrode is a useful alternative especially when anchor bolt is not available such as in country with limited resources or is less appropriate such as placement in patients with thin skull or at the occiput area, despite some drawbacks including potential dislodgement. While the accuracy of implantation using anchor bolt is well-studied, data on boltless implantation remain scarce. This study aimed to reveal the accuracy, permissible error for actual placement of electrodes within the grey matter, and delayed electrode dislodgement in boltless implantation. A total of 120 electrodes were implanted in 15 patients using a Leksell Stereotactic G Frame with each electrode fixed on the scalp using sutures. Target point error was defined as the Euclidean distance between the planned target and the electrode tip on immediate postimplantation computed tomography. Similarly, delayed dislodgement was defined as the Euclidean distance between the electrode tips on immediate postimplantation computed tomography and delayed MRI. The factors affecting accuracy were evaluated using multiple linear regression. The permissible error was defined as the largest target point error that allows the maximum number of planned gray matter electrode contacts to be actually placed within the gray matter as intended. The median (IQR) target point error was 2.6 (1.7-3.5) mm, and the permissible error was 3.2 mm. The delayed dislodgement, with a median (IQR) of 2.2 (1.4-3.3) mm, was dependent on temporal muscle penetration (P = 5.0 × 10-4), scalp thickness (P < 5.1 × 10-3), and insertion angle (P = 3.4 × 10-3). Boltless implantation of stereo-electroencephalography electrode offers an accuracy comparable to those using anchor bolt. During the planning of boltless implantation, target points should be placed within 3.2 mm from the gray-white matter junction and a possible delayed dislodgement of 2.2 mm should be considered.

Suture materials in maxillofacial surgery – A comprehensive review

By holding tissues together to speed up the healing process, surgical sutures are used to secure and restore active or trauma-induced wounds. In dentistry, a variety of sutures are employed. Both absorbable and nonabsorbable suture materials are part of the primary category. A well-fitting suture prevents the displacement forces caused by external agents, functional movements, and muscle insertions. The potential of novel suture materials to resemble wounds and cure wounds is driving up their manufacture in recent times. In order to help the clinician obscure the best possible soft tissue care, this review provides an update on the features and guiding principles of suture selection.

Levator ani muscle avulsion and subsequent vaginal delivery: 8-year longitudinal follow-up.

To assess the evolution of levator ani muscle (LAM) avulsion from 1 year to 8 years after first delivery in women with and those without subsequent vaginal delivery. In addition, to assess whether women with full or partial avulsion 8 years after first delivery have larger LAM hiatal area and more symptoms of pelvic organ prolapse compared to women with normal LAM insertion. In this single-center longitudinal study, 195 women who were primiparous at the start of the study were included and underwent transperineal ultrasound examination 1 year and 8 years after first delivery. Muscle insertion was assessed by tomographic ultrasound imaging in the axial plane. Full LAM avulsion was defined as abnormal muscle insertion in all three central slices. Partial LAM avulsion was defined as abnormal muscle insertion in one or two central slices. Eight years after the first delivery, LAM hiatal area was assessed at rest, during maximum pelvic floor muscle contraction and on maximum Valsalva maneuver. To assess symptoms of pelvic organ prolapse, the vaginal symptoms module of the International Consultation on Incontinence Questionnaire was used. At 1-year follow-up, 25 (12.8%) women showed signs of LAM avulsion, of whom 20 fulfilled the sonographic criteria of full avulsion and five of partial avulsion. Eight years after the first delivery, 35 (17.9%) women were diagnosed with avulsion, of whom 25 were diagnosed with full avulsion and 10 with partial avulsion. No woman with partial or full avulsion at 1 year had improved avulsion status at the 8-year follow-up. Of the 150 women who had subsequent vaginal delivery, 21 (14.0%) women were diagnosed with partial or full LAM avulsion 1 year after first delivery, and 31 (20.7%) women were diagnosed with partial or full avulsion 8 years after first delivery. Of the 45 women without subsequent vaginal delivery, one woman with partial avulsion 1 year after first delivery was diagnosed with full avulsion at the 8-year follow-up. All women with full avulsion at 1-year follow-up were diagnosed with full avulsion at the 8-year follow-up regardless of whether they had subsequent vaginal delivery. At 8-year follow-up, women with full avulsion had statistically significantly larger LAM hiatal area compared to women with normal muscle insertion. Mean ± SD vaginal symptom scores ranged between 5.5 ± 5.7 and 6.0 ± 4.0 and vaginal symptom quality of life scores ranged between 0.9 ± 1.4 and 1.5 ± 2.2 and did not differ significantly between women with normal muscle insertion and women with partial or full avulsion at 8-year follow-up. More LAM avulsions were present 8 years compared with 1 year after first delivery in women with subsequent vaginal delivery. Except for one primipara, all women without subsequent vaginal delivery had unchanged LAM avulsion status between 1 year and 8 years after their first delivery. Larger LAM hiatal area was found in women with full avulsion compared to those with normal muscle insertion at 8-year follow-up. Vaginal symptoms scores were low and did not differ between women with normal muscle insertion and those with partial or full avulsion at 8-year follow-up. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

What Is New about the Semimembranosus Distal Tendon? Ultrasound, Anatomical, and Histological Study with Clinical and Therapeutic Application.

The semimembranosus muscle inserts into several tendons that are associated with some pathologies. Although ultrasound is useful for studying, diagnosing, and managing these pathologies, the correct interpretation of any images requires a clear knowledge of the related anatomical structures and the inter-related functions. We studied 38 cryopreserved non-paired knees from adult anatomical specimens and 4 non-paired knees from 29 to 38-week-old fetuses. The semimembranosus muscle and its tendons were located, observed, and injected under ultrasound guidance. The macroscopic anatomy was studied using dissection and anatomical cuts and the tendons were analyzed histologically. Measurements of muscle were taken 10 cm from the medial epicondyle and just before the tendon divided. The ultrasound facilitated the identification of the different divisions of the tendon of semimembranosus muscle and the rotation of the muscle and tendon from medial to posterior. An anatomical study confirmed this rotation and revealed an average width, thickness, and diameter of 38.29 mm, 14.36 mm, and 112.64 mm, respectively. Important relationships were observed between the divisions of the main tendons and the medial collateral ligament, the posterior side of the knee and popliteus muscle. This information can help to explain knee pathologies and facilitate rehabilitation after surgery.

Exceptional In Situ Preservation of Chondrocranial Elements in a Coniacian Mosasaurid from Colombia

The first record of well-preserved chondrocranial elements in mosasaurids is here described. These elements are preserved in situ in a Coniacian skull found in north-central Colombia, inside a calcareous concretion. Based on a 3D model generated from computed tomography scans, we identified elements of the nasal and orbitotemporal regions. Our descriptions show that in this specimen, the chondrocranium was reduced, more so than in most lacertilians (including their closest recent relatives, the varanids), but not as severely as in snakes or amphisbaenians (which have an extremely reduced chondrocranium and limbs). The new evidence suggests that the reduction in the chondrocranium in mosasaurids could be related to modification of their limbs when adapting to aquatic environments, but also that in mosasaurids, the olfactory tract was reduced, and the optic muscle insertions occurred mainly in the interorbital septum. The exceptional preservation of the chondrocranial elements in the specimen is facilitated by a gray mineralization covering them. XRD analysis and thin section observations indicated that this mineralization is composed of microcrystalline quartz and calcite. We infer that this material was produced by a partial silicification process promoted by lower pH microenvironments associated with bacterial breakdown of non-biomineralized tissues during early diagenesis.

Insertions of the striated muscles in the skin and mucosa: a histological study of fetuses and cadavers.

Striated muscle insertions into the skin and mucosa are present in the head, neck, and pelvic floor. We reexamined the histology of these tissues to elucidate their role in transmission of the force. We examined histological sections of 25 human fetuses (gestational ages of ~11-19 weeks and ~26-40 weeks) and 6 cadavers of elderly individuals. Facial muscle insertion or terminal almost always formed as an interdigitation with another muscle or as a circular arrangement in which muscle fiber insertions were sandwiched and mechanically supported by other muscle fibers (like an in-series muscle). Our examination of the face revealed some limited exceptions in which muscle fibers that approached the dermis were always in the nasalis and mentalis muscles, and often in the levator labii superioris alaeque nasi muscle. The buccinator muscle was consistently inserted into the basement membrane of the oral mucosa. Parts of the uvulae muscle in the soft palate and of the intrinsic vertical muscle of the tongue were likely to direct toward the mucosa. In contrast, the pelvic floor did not contain striated muscle fibers that were directed toward the skin or mucosa. Although 'cutaneous muscle' is a common term, the actual insertion of a muscle into the skin or mucosa seemed to be very rare. Instead, superficial muscle insertion often consisted of interdigitated muscle bundles that had different functional vectors. In this case, the terminal of one muscle bundle was sandwiched and fixed mechanically by other bundles.

Evaluation of macular vessel density with OCTA in patients undergoing inferior oblique muscle surgery

Aims: To evaluate pre- and postoperative macular vascular density changes in patients undergoing inferior oblique muscle surgery using optical coherence tomography angiography (OCTA). Methods: 28 eyes of 16 patients who underwent inferior oblique muscle surgery were included in the study. Measurements were taken preoperatively (T0) and one day (PO1), 15 days (PO15) and 6 weeks (PO6w) after surgery. The vessel densities of the superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris (CCL) were measured by OCTA. Results: This study included 28 eyes of 16 patients. The mean age of the patients was 8.07±5.5 years (4-23 years). SCP and DCP mean vascular densities decreased significantly at PO1 and PO15 compared to T0, but increased at PO6w, reaching their initial levels. Mean CCL levels were lower at PO1 compared to all other measurements and reached their preop values at PO6w. Conclusion: The inferior oblique muscle insertion is known to be close to the macula and surgical interventions for this muscle may cause changes in macular vascular density. In our study, macular vascular density decreased in all parameters at PO1 compared to T0, but almost reached its preop levels at PO6w.

The Spiral of Tillaux: dead on accurate; a cadaveric study

ABSTRACT Introduction The Spiral of Tillaux describes the historically accepted insertion distances of the medial rectus, inferior rectus, lateral rectus, and superior rectus from the limbus: 5.5 mm, 6.5 mm, 6.9 mm, and 7.7 mm, respectively. The corneal diameters are historically accepted to be 11.7 mm horizontally and 10.6 mm vertically in adults. We investigated the variability of the insertion distances of the extraocular rectus muscles from the limbus as well as the corneal diameters using eyes from human cadavers and compared our measurements to these historically accepted measurements. Methods A sample of 60 eyes were included. For each eye, a 360 peritomy was conducted and the conjunctiva bluntly dissected to view the sclera. Muscle hooks were utilized to isolate the extraocular rectus muscles. Calipers were used to measure the insertion distances of the rectus muscles as well as the corneal diameters. Results The mean rectus muscle insertions distances from the limbus were medial 5.28 mm, inferior 5.72 mm, lateral 6.40 mm, and superior 6.78 mm. These insertion distances were shorter than the historical benchmarks (p < .01). However, observed maximum distances of the rectus muscles were all greater than the historically accepted benchmarks, with the medial, inferior, lateral, and superior rectus muscles being 6.4 mm, 7.3 mm, 7.4 mm, and 7.8 m from the limbus, respectively. The mean width and height of the cornea were 11.7 mm and 10.7 mm, respectively, and similar to the expected ranges. Conclusion This study concludes that variability does exist from the historically accepted Spiral of Tillaux measurements. In addition, significant variation exists between male and female rectus muscle insertions. However, we did confirm that the rectus muscles followed the same spiral pattern described by the Spiral of Tillaux and concluded that the corneal diameters are consistent with previously accepted values.

Anatomy of the Lumbrical Muscles: Implications for Mechanical Advantage.

The lumbrical muscles comprise 4 intrinsic muscles of the hand and are involved in flexion of the metacarpophalangeal joint (MCPJ) and extension of the proximal interphalangeal and distal interphalangeal joints. The purpose of this study was to investigate the anatomical mechanics of the lumbrical muscles of the index, middle, ring, and small fingers. We evaluated 25 cadaver arms and measured the distance between the MCPJ and fingertip, the distance between the MCPJ and lumbrical muscle insertion, and the distance between the MCPJ and the most proximal lumbrical muscle origin. With these measurements we calculated the needed force, insertion ratio (length of the proximal, middle, and distal phalanx divided by the MCPJ to insertion distance), and lumbrical muscle length. We found that the force was significantly different between all fingers, except for the comparison of the index and ring finger (P = .34). In addition, we found that muscle length was significantly different between most the fingers, except for the comparison between the index and middle fingers (P = .24), and index and ring fingers (P = .20). There was no significant difference in insertion ratio. Our study suggests that the anatomical mechanics for the motor function of the lumbrical muscles are similar in all fingers. This could further imply that movements are equally precise in all fingers resulting in coordination with one another and, therefore, adequate hand function. IV.

Prediction of jaw opening function after mandibular reconstruction using subject-specific musculoskeletal modelling.

Mandibular reconstruction patients often suffer abnormalities in the mandibular kinematics. In silico simulations, such as musculoskeletal modelling, can be used to predict post-operative mandibular kinematics. It is important to validate the mandibular musculoskeletal model and analyse the factors influencing its accuracy. To investigate the jaw opening-closing movements after mandibular reconstruction, as predicted by the subject-specific musculoskeletal model, and the factors influencing its accuracy. Ten mandibular reconstruction patients were enrolled in this study. Cone-beam computed tomography images, mandibular movements, and surface electromyogram signals were recorded preoperatively. A subject-specific mandibular musculoskeletal model was established to predict surgical outcomes using patient-averaged muscle parameter changes as model inputs. Jaw bone geometry was replaced by surgical planning results, and the muscle insertion sites were registered based on the non-rigid iterative closest point method. The predicted jaw kinematic data were validated based on 6-month post-operative measurements. Correlations between the prediction accuracy and patient characteristics (age, pathology and surgical scope) were further analysed. The root mean square error (RMSE) for lower incisor displacement was 31.4%, and the error for peak magnitude of jaw opening was 4.9 mm. Age, post-operative infection and radiotherapy influenced the prediction accuracy. The amount of masseter detachment showed little correlation with jaw opening. The mandibular musculoskeletal model successfully predicted short-range jaw opening functions after mandibular reconstruction. It provides a novel surgical planning method to predict the risk of developing trismus.

Zip-up Loop Myopexy in Heavy Eye Syndrome.

To describe and report the results of a zip-up modification for loop myopexy for facilitating a muscle union procedure in heavy eye syndrome. A retrospective chart review was conducted on patients with heavy eye syndrome in whom the modified surgical technique was performed. Superior and lateral rectus muscle bellies were approximated using a suture 4 to 5 mm from the muscle insertion. Muscles were then zipped together by 5-0 polyester sutures placed in an anteroposterior direction using a hand-over-hand technique. Details of the surgical technique were reported. Ductions, versions, and angles of strabismus were evaluated before and after surgery. Complications were reported. A total of 8 patients were identified (mean age: 60.8 ± 7 years). Mean axial length was 33.2 ± 1.2 mm. Mean preoperative horizontal and vertical angles of deviation were 78 ± 20 prism diopters (PD) (range: 50 to 120 PD) and 34 ± 4 PD (range: 30 to 40 PD), respectively. Preoperative limitation of abduction and elevation was -4 to -5 in all patients. An average of seven to eight sutures were used. No intraoperative complications were reported. In 7 patients, both vertical and horizontal angles of deviation were reduced to within 8 PD from orthophoria and limitation of ductions was reduced to null or -1 after surgery. Undercorrection occurred in 1 patient with bilateral heavy eye syndrome who had unilateral surgery. No recurrences developed over a median of 6 months of follow-up. A zip-up modification for loop myopexy can facilitate the surgical procedure to achieve a satisfactory outcome in heavy eye syndrome. [J Pediatr Ophthalmol Strabismus. 2024;61(4):279-286.].

Three Key Submuscular Points for Nonsurgical Rejuvenation of the Midface in Caucasian Patients: A Methodological Approach Using Injectable Hyaluronic Acid Fillers.

Since aesthetic medical treatments providing natural results are becoming increasingly popular, we developed an innovative hyaluronic acid infiltration technique for midface rejuvenation. In this prospective study, only patients with a negative or neutral lower eyelid vector were included. Treatment consisted in injecting three hyaluronic acid boluses at the cutaneous projections of the levator labii superioris, zygomatic major and minor muscles insertions. All patients were administered before treatment the FACE-Q questionnaire, whereas after treatment, they were administered the FACE-Q questionnaire and the Global Aesthetic Improvement Scale (GAIS). All treatments were documented with standardized photographs. A plastic surgeon from another Institution reviewed the photos and scored the treatments according to the GAIS scale. We included 567 patients (101 males and 466 females) who met the inclusion criteria. The mean age was 41 years, and mean follow-up time was four months. The FACE-Q scores after treatment were significantly higher (p < 0.001) in every domain investigated. The GAIS scores demonstrated significant improvement posttreatment in 89.8% of patients. An average of 1.5 ml of hyaluronic acid (VYC-20) was used for each zygomatic region. No major complications were reported; only 27 patients reported bruising, which resolved spontaneously. In all patients, there was an inversion of the lower eyelid vector, which had transitioned from neutral or negative to positive. Lifting the insertions of three selected muscles with hyaluronic acid allows a midface upward repositioning. This technique provides a reproducible and safe approach for midface rejuvenation through tissue repositioning rather than augmenting facial volume. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Growing stylohyoideus muscle insertion to the hyoid bone with special reference to its topographical relation to the intermediate tendon of digastricus muscle: A histological study using human fetuses

BackgroundIn adults, the intermediate tendon of digastricus muscle usually runs along the medial or lateral side of the stylohyoideus muscle insertion. To provide a better understanding of the variations, we examined the topographical anatomy of the muscle and tendon in fetuses. MethodsWe examined histological sections from six early-term, 26 mid-term and six near-term fetuses (approximately 8–9, 12–18 weeks and 25–33 weeks). ResultsAt early-term, an initial sheath of intermediate tendon of digastricus muscle received the stylohyoideus muscle at the superior aspect. The muscle and tendon was distant from the hyoid. At mid-term, near the insertion to the hyoid greater horn, the stylohyoideus muscle consistently surrounded more than 2/3 of the intermediate tendon circumference. In contrast, we found no near-term specimen in which the stylohyoideus muscle surrounded the intermediate tendon. The multilayered tendon sheath was fully developed until near-term and connected to the body of hyoid by an intermuscular septum between the thyrohyoideus muscle and one or two of suprahyoid muscles. Therefore, the hyoid insertion of the styloglossus muscle was a transient morphology at mid-term. ConclusionThe stylohyoideus muscle insertion was appeared to move from the tendon sheath to the hyoid greater horn and, until near-term, return to the tendon sheath. A fascia connecting the tendon sheath to the body of hyoid was strengthened by the suprahyoid and infrahyoid muscles. The latter muscles seemed to regulate fixation/relaxation of the intermediate tendon to the hyoid. The stylohyoideus muscle slips sandwiching the intermediate tendon might be a rare morphology.

Morphological variation, modularity and integration in the scapula and humerus of Lissotriton newts.

The modular organization of tetrapod paired limbs and girdles, influenced by the expression of Hox genes is one of the primary driving forces of the evolution of animal locomotion. The increased morphological diversification of the paired limbs is correlated with reduced between-limb covariation, while correlation within the elements is usually higher than between the elements. The tailed amphibians, such as Lissotriton newts, have a biphasic lifestyle with aquatic and terrestrial environments imposing different constraints on limb skeleton. By employing the methods of computerized microtomography and 3D geometric morphometrics, we explored the pattern of morphological variation, disparity, modularity and morphological integration in the proximal parts of the anterior limbs of six species of Eurasian small bodied newts. Although the species significantly differ in limb shape, there is a great overlap in morphology of scapula and humerus, and there are no differences in morphological disparity. For the scapula, the shape differences related to the duration of the aquatic period are in length, depth and curvature. The shape of the humerus is not affected by the length of aquatic period, and shape differences between the species are related to robustness of the body. The length of aquatic period has statistically supported phylogenetic signal. The scapula and humerus are structures of varying modularity. For the humerus, the strongest support on the phylogenetic level was for the capitulum/shaft hypothesis, which can also be interpreted as functional modularity. For the scapula, the greatest support was for the antero-posterior hypothesis of modularity in case of Lissotriton vulgaris, which can be explained by different functional roles and muscle insertion patterns, while there was no phylogenetic modularity. The modularity patterns seem to correspond with the general tetrapod pattern, with modularity being more pronounced in the distal structure. The future research should include more salamandrid taxa with different habitat preferences and both adult and larval stages, in order to explore how size, phylogeny and ecology affect the morphology and covariation patterns of limbs.

Comparison of exposure of the radius afforded by the craniomedial and craniolateral open surgical approaches in dog cadavers.

Management of antebrachial fractures in dogs typically involves open reduction and bone plate stabilisation of the radius performed using either a craniomedial approach (CMA) or craniolateral approach (CLA). The aim of this cadaveric study was to compare radial exposure afforded via the craniomedial and craniolateral approaches, without and with releasing the abductor digiti I longus (ADIL) muscle. The CMA and CLA were performed on alternate paired cadaver forelimbs with the subsequent release (CMA) or elevation (CLA) of the ADIL muscle (n = 12). The percent area of exposure was calculated in defined longitudinal radial segments (LRSs) and hemi-circumferential radial segments (HRSs) using digitally uploaded images. A non-parametric rank sum test was used for statistical analysis (p < 0.05). While both the CMA and CLA provided sufficient exposure for radial cranial plate placement in the mid-to-distal diaphyseal region (50-80% LRSs), the CMA afforded greater exposure to the distal metaphysis (80-90% LRS). The CLA was advantageous in exposing the proximal diaphysis (20-50% LRSs) and distal epiphysis (90-100% LRS). Exposure of the distal diaphyseal, metaphyseal, and epiphyseal regions (80-100% LRSs) was impeded by the ADIL muscle. A tenotomy of the tendon of insertion of the ADIL muscle increased exposure afforded by the CMA in the distal metaphyseal and epiphyseal regions. The exposure afforded by the CLA in the distal diaphyseal and metaphyseal regions was significantly improved by elevating the origin of the ADIL muscle. The results of this study provide useful clinical information when surgeons are deciding which approach to use for cranial radial plating.