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Journal of Anatomy Jul 2022The morphology of the more superficial tissue of the human tongue was investigated and discussed with the clinical appearance of fissures. Three regions could be...
The morphology of the more superficial tissue of the human tongue was investigated and discussed with the clinical appearance of fissures. Three regions could be distinguished according to the presence and shape of the aponeurosis linguae: the central region showed a thick aponeurotic plate with myotendinous muscle fibre insertions. The lateral region showed still an aponeurosis linguae but of reduced thickness and without muscle insertions. The edge-wise and lower region showed no aponeurosis linguae but a fatty subcutis and myocutaneous muscle fibre insertions lacking specific molecules of myotendinous junctions. This system of partially developed exoskeleton seems to underlie but not to be involved in tongue fissures, which are more superficial within the epidermis and dermis.
Topics: Aponeurosis; Humans; Muscle Fibers, Skeletal; Muscle, Skeletal; Tendons; Tongue
PubMed: 35137396
DOI: 10.1111/joa.13637 -
The Journal of Craniofacial Surgery Nov 2016The aim of this study was to examine the superoinferior extension of the post-levator aponeurosis fat pad in the upper eyelids of Japanese cadavers. Twenty-six upper...
The aim of this study was to examine the superoinferior extension of the post-levator aponeurosis fat pad in the upper eyelids of Japanese cadavers. Twenty-six upper eyelids (12 right and 14 left) from 15 Japanese cadavers (6 men and 9 women; average age at death, 82.1 years) were used in this experimental anatomical study. After an orbital exenteration, the tissues were cut sagittally through the center of the orbit, and the superoinferior extension of the post-levator aponerosis fat pad was microscopically examined on the sections. Consequently, the fat pad superiorly reached the myotendinous junction between the levator aponeurosis and the levator palpebrae superioris (LPS) muscle in 17 eyelids with the nonbranching LPS muscle. The fat pad extended to the roots of the superior and inferior branches of the LPS muscle in the other 9 eyelids with the branching LPS muscle. Inferiorly, the fat pad was limited to the conjunctival fornix in 13 eyelids, but reached the tarsal plate in the other 13 eyelids. This study showed anatomical variation in the superoinferior extension of the post-levator aponerosis fat pad in Japanese cadavers.
Topics: Adipose Tissue; Aged, 80 and over; Aponeurosis; Cadaver; Connective Tissue; Eyelids; Female; Humans; Male; Oculomotor Muscles; Orbit
PubMed: 28005782
DOI: 10.1097/SCS.0000000000003088 -
Ophthalmic Plastic and Reconstructive... 2017To investigate biomechanical properties of the levator aponeurosis.
PURPOSE
To investigate biomechanical properties of the levator aponeurosis.
METHODS
Patients undergoing external levator resection for primary or revision correction of acquired ptosis were analyzed as primary and revision groups. Immediately postoperatively, the resected segments of the levator aponeurosis were stressed by adding sequential masses to the tissue. Specimen length was recorded at each stress level. Stress-strain diagrams were used to summarize how the tissue elongated in response to the external forces, because these diagrams correct for differences in specimen size. Representative specimens were analyzed histologically.
RESULTS
Twenty-two specimens from 14 patients in the primary group and 10 specimens from 7 patients in the revision group met inclusion criteria. In the primary group, the mean age was 66 years; 8 patients were women. In the revision group, the mean age was 69 years; 6 patients were women. Levator aponeurosis specimens in both the primary and revision group demonstrated proportional increases in length with increasing stress, demonstrating that the levator aponeurosis is extensile. Given the same amount of stress, the levator aponeurosis from primary specimens elongated more than revision specimens. Histologically, revision specimens exhibited increased collagen and haphazard, tangled elastin fibers.
CONCLUSIONS
The levator aponeurosis obtained during surgical correction of acquired ptosis elongates in response to nominal external forces. This biomechanical property is important because the length of the aponeurosis may vary intraoperatively if variable forces are applied to the eyelid. This property might be related to connective tissue architecture and, specifically, fibrosis. Surgeons performing levator aponeurosis resection should be mindful to maintain a consistent amount of force on the levator aponeurosis when performing the resection to maximize intercase consistency.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Aponeurosis; Biomechanical Phenomena; Blepharoplasty; Blepharoptosis; Eyelids; Female; Humans; Male; Middle Aged; Young Adult
PubMed: 27517973
DOI: 10.1097/IOP.0000000000000731 -
Journal of Applied Physiology... Aug 2018Aponeuroses are connective tissues found on the surface of pennate muscles and are in close association with muscle fascicles. In addition to transmitting muscle forces...
Aponeuroses are connective tissues found on the surface of pennate muscles and are in close association with muscle fascicles. In addition to transmitting muscle forces to the external tendon, aponeurosis has been hypothesized to influence the direction of muscle shape change during a contraction. Muscle shape changes affect muscle contractile force and velocity because they influence the gear ratio with which muscle fascicles transmit force and velocity to the tendon. If aponeurosis modulates muscle shape changes, altering the aponeurosis' radial integrity with incisions should alter gearing. We tested the hypothesis that incising the aponeurosis would lead to decreased gearing across force conditions with an in situ preparation of the turkey lateral gastrocnemius muscle. We found that multiple full-length incisions in the aponeurosis altered the relationship between gearing and force relative to the intact aponeurosis condition. Specifically, after multiple aponeurosis incisions, gear ratio decreased by 19% in the high-force contractions compared with the intact condition. These results suggest that aponeuroses influence muscle shape change and can alter muscle contractile force and speed through their effect on muscle gearing. NEW & NOTEWORTHY Muscle gearing is determined by muscle shape change during a contraction and varies with the force of contraction. Variable gearing influences muscle force and speed, but how gearing is modulated is not well understood. Incising the aponeurosis before and after contractions demonstrates that aponeurosis plays a role in modulating gearing.
Topics: Animals; Aponeurosis; Biomechanical Phenomena; Mechanical Phenomena; Muscle Contraction; Muscle, Skeletal; Tendons; Turkeys
PubMed: 29792551
DOI: 10.1152/japplphysiol.00151.2018 -
International Journal of Sports Medicine Sep 2021Lower stiffness of the medial longitudinal arch is reportedly a risk factor for lower leg disorders. The plantar aponeurosis is considered essential to maintaining the...
Lower stiffness of the medial longitudinal arch is reportedly a risk factor for lower leg disorders. The plantar aponeurosis is considered essential to maintaining the medial longitudinal arch. It is therefore expected that medial longitudinal arch stiffness is influenced by plantar aponeurosis stiffness. However, this has not been experimentally demonstrated. We examined the relationship between the plantar aponeurosis stiffness and medial longitudinal arch stiffness in humans in vivo. Thirty young subjects participated in this study. The navicular height and shear wave velocity (an index of stiffness) of the plantar aponeurosis were measured in supine and single-leg standing positions, using B-mode ultrasonography and shear wave elastography, respectively. The medial longitudinal arch stiffness was calculated based on body weight, foot length, and the difference in navicular height between the supine and single-leg standing conditions (i. e., navicular drop). Shear wave velocity of the plantar aponeurosis in the supine and single-leg standing positions was not significantly correlated to medial longitudinal arch stiffness (spine: r=-0.14, P=0.45 standing: r=-0.16, P=0.41). The findings suggest that the medial longitudinal arch stiffness would be strongly influenced by the stiffness of foot structures other than the plantar aponeurosis.
Topics: Adult; Aponeurosis; Elasticity Imaging Techniques; Female; Foot; Humans; Male; Tarsal Bones; Ultrasonography; Young Adult
PubMed: 33621994
DOI: 10.1055/a-1373-5734 -
Journal of Biomechanics Apr 2023The plantar aponeurosis functions to support the foot arch during weight bearing. Accurate anatomy and material properties are critical in developing analytical and...
The plantar aponeurosis functions to support the foot arch during weight bearing. Accurate anatomy and material properties are critical in developing analytical and computational models of this tissue. We determined the cross-sectional areas and material properties of four regions of the plantar aponeurosis: the proximal middle and distal middle portions of the tissue and the medial (to the first ray) and lateral (to the fifth ray) regions. Bone-plantar aponeurosis-bone specimens were harvested from fifteen cadaveric feet. Cross-sectional areas were measured using molding, casting, and sectioning methods. Mechanical testing was performed using displacement control triangle waves (0.5, 1, 2, 5, and 10 Hz) loaded to physiologic tension by estimating from body weight and area ratio of the region. Five specimens were tested for each region. Regional deformations were recorded by a high-speed video camera. There were overall differences in cross-sectional areas and biomechanical behavior across regions. The stress-strain responses are non-linear and mainly elastic (energy loss 3.6% to 7.2%). Moduli at the proximal middle and distal middle regions (400 and 522 MPa) were significantly higher than the medial and lateral regions (225 and 242 MPa). The effect of frequency on biomechanical outcomes was small (e.g., 3.5% change in modulus), except for energy loss (107% increase as frequency increased from 0.5 to 10 Hz). These results indicate that the plantar aponeurosis tensile response is non-linear, nearly elastic, and frequency independent. The cross-sectional area and material properties differ by region, and we suggest that such differences be included to accurately model this structure.
Topics: Humans; Aponeurosis; Foot; Weight-Bearing; Bone and Bones; Models, Biological; Biomechanical Phenomena
PubMed: 36924529
DOI: 10.1016/j.jbiomech.2023.111531 -
Journal of Anatomy Jul 2020The plantar aponeurosis in the human foot has been extensively studied and thoroughly described, in part, because of the incidence of plantar fasciitis in humans. It is...
The plantar aponeurosis in the human foot has been extensively studied and thoroughly described, in part, because of the incidence of plantar fasciitis in humans. It is commonly assumed that the human plantar aponeurosis is a unique adaptation to bipedalism that evolved in concert with the longitudinal arch. However, the comparative anatomy of the plantar aponeurosis is poorly known in most mammals, even among non-human primates, hindering efforts to understand its function. Here, we review previous anatomical descriptions of 40 primate species and use phylogenetic comparative methods to reconstruct the evolution of the plantar aponeurosis and its relationship to the plantaris muscle in primates. Ancestral state reconstructions suggest that the overall organization of the human plantar aponeurosis is shared with chimpanzees and that a similar anatomical configuration evolved independently in different primate clades as an adaptation to terrestrial locomotion. The presence of a plantar aponeurosis with clearly developed lateral and central bands in the African apes suggests that this structure is not prohibitive to suspensory locomotion and that these species possess versatile feet adapted for both terrestrial and arboreal locomotion. This plantar aponeurosis configuration would have been advantageous in enhancing foot stiffness for bipedal locomotion in the earliest hominins, prior to the evolution of a longitudinal arch. Hominins may have subsequently evolved thicker and stiffer plantar aponeuroses alongside the arch to enable a windlass mechanism and elastic energy storage for bipedal walking and running, although this idea requires further testing.
Topics: Animals; Aponeurosis; Biological Evolution; Foot; Gait; Hominidae; Humans; Locomotion; Phylogeny; Primates; Walking
PubMed: 32103502
DOI: 10.1111/joa.13173 -
In Vivo (Athens, Greece) 2022Masticatory muscle tendon-aponeurosis hyperplasia (MMTAH) is a disease associated with a mouth opening limitation. Here, we conducted a bioinformatics analysis to...
BACKGROUND/AIM
Masticatory muscle tendon-aponeurosis hyperplasia (MMTAH) is a disease associated with a mouth opening limitation. Here, we conducted a bioinformatics analysis to examine gene expression patterns in patients with MMTAH in comparison to those with facial deformity (FD).
MATERIALS AND METHODS
Seven MMTAH patients and three FD patients were recruited. We conducted RNA sequencing analysis, quantitative reverse transcription polymerase chain reaction and immunoblot analysis.
RESULTS
Of the identified 19,767 mapped read tags that showed clear differential expression, 2,471 genes were significantly up-regulated and 2,849 genes were significantly down-regulated in patients with MMTAH compared to those in patients with FD. Among the up-regulated genes, ten genes were significantly increased. The distribution of up-regulated and down-regulated genes at different ages tended to be similar. Moreover, the protein levels of Ankyrin Repeat Domain 2, Troponin T1 and myosin heavy chain 7, which are associated with slow twitch fibers and mechanical loading, were strongly expressed in patients with MMTAH compared to those in patients with FD.
CONCLUSION
The gene expression pattern in MMTAH patients was similar regardless of age. As the transition of fast-to-slow twitch in the skeletal muscle is induced by mechanical loading, and up-regulation of slow twitch molecules was observed in MMTAH patients, mechanical loading is suggested to be implicated in MMTAH.
Topics: Aponeurosis; High-Throughput Nucleotide Sequencing; Humans; Hyperplasia; Masticatory Muscles; Muscle, Skeletal; Tendons
PubMed: 35241507
DOI: 10.21873/invivo.12738 -
Journal of Plastic, Reconstructive &... Jun 2021Conventional aponeurotic surgery for blepharoptosis has many advantages, but there is a potential for recurrence and lagophthalmos. The anatomy of the levator palpebrae...
BACKGROUND
Conventional aponeurotic surgery for blepharoptosis has many advantages, but there is a potential for recurrence and lagophthalmos. The anatomy of the levator palpebrae muscle is relatively well studied, but the relationship of levator aponeurosis with surrounding layers is still controversial. This study aims to prove the presence of an anterior layer of the levator aponeurosis in clinical cases and to describe a technique involving its use for obtaining predictable outcomes in blepharoptosis correction.
METHODS
Between January 2014 and October 2018, 173 patients with blepharoptosis underwent correction surgery that involved relocating the anterior layer of the levator aponeurosis. During this procedure, after retracting the preaponeurotic fat pad, we could identify the misinserted anterior layer of the levator aponeurosis on the floor of the fat pad. The anterior layer was divided and advanced with posterior layers to 2 mm below the upper margin of the tarsus. After surgery, patients were followed up for 1 year, and surgical outcomes were evaluated.
RESULTS
After 1 year of follow-up, 95.4% of the examined patients showed good long-term outcomes. Moreover, although 4% showed moderate outcomes and lost the double eyelid skin crease, there was no ptosis recurrence in these patients and no lagophthalmos occurred in any of the 173 patients.
CONCLUSIONS
The authors found the misinserted anterior layer of the levator aponeurosis at the floor of preaponeurotic fat pad in blepharoptosis patients. Relocation of the anterior layer can provide predictable outcomes without lagophthalmos in blepharoptosis correction.
Topics: Aponeurosis; Blepharoplasty; Blepharoptosis; Eyelids; Female; Follow-Up Studies; Humans; Male; Middle Aged; Oculomotor Muscles; Outcome and Process Assessment, Health Care; Postoperative Complications; Risk Adjustment; Time
PubMed: 33358565
DOI: 10.1016/j.bjps.2020.10.040 -
Sbornik Lekarsky Mar 1991The plantar aponeurosis begins to differentiate from two separate blastemas in the subcutaneous area of the planta in embryos 20-25 mm long. The basis of the lateral...
The plantar aponeurosis begins to differentiate from two separate blastemas in the subcutaneous area of the planta in embryos 20-25 mm long. The basis of the lateral (fibular) strip is in 30 mm long embryos still larger than the blastema of the medial (tibial) strip. In embryos longer than 40 mm first the ratio of sizes of the two strips becomes equal and gradually there develops a predominance of the medial (tibial) tract. Both originally isolated bases of the plantar aponeurosis fuse gradually in 30-40 mm long embryos. 2. In the course of early development the bases of the aponeurosis are distinctly separated from the base of the m. flexor digitorum brevis. The aponeurosis becomes close to the basis of the flexor only in embryos longer than 45 mm. 3. The insertion of the plantar muscle is not related to the plantar aponeurosis during ontogenetic development. The development of the two formations is quite independent and the tendon of the m. plantaris becomes adjacent to the tendon of the m. triceps surae. 4. In the course of development we found three typical sites of insertions of the main-medial-strip of the plantar aponeurosis: a) primary insertion of the transverse fascia of the aponeurosis and the major part of the longitudinal strips leads to the vaginae fibrosae of the flexor tendons; b) the splitting longitudinal strips which lead to the plantar and lateral surface of the capsules of the metatarsophalangeal joints; c) rare longitudinal fascia of the aponeurosis end in the subcutaneous area on the plantar side of the toes. The tractus lateralis (fibularis) joins the fascia covering the muscles of the little toe.
Topics: Foot; Humans; Tendons
PubMed: 2047746
DOI: No ID Found