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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 -
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 -
Frontiers in Cell and Developmental... 2021The roles of bone morphogenetic protein (BMP) signaling in palatogenesis were well documented in the developing hard palate; however, little is known about how BMP...
The roles of bone morphogenetic protein (BMP) signaling in palatogenesis were well documented in the developing hard palate; however, little is known about how BMP signaling regulates the development of soft palate. In this study, we overexpressed transgene via allele to suppress BMP signaling in the developing soft palate. We found that BMP-Smad signaling was detected in the palatal muscles and surrounding mesenchyme. When BMP-Smad signaling was suppressed by the overexpressed , the soft palatal shelves were reduced in size with the hypoplastic muscles and the extroversive hypophosphatasia (HPP). The downregulated cell proliferation and survival in the soft palates were suggested to result from the repressed transcription and Gli1 activity, implicating that the BMP-Shh-Gli1 network played a similar role in soft palate development as in the hard palate. The downregulated Sox9, (), and expression in soft palate indicated the impaired differentiation of the aponeurosis and tendons, which was suggested to result in the hypoplasia of palatal muscles. Intriguingly, in the and the soft palates, the hypoplastic or abrogated muscles affected little the fusion of soft palate. Although the , , and transcription was significantly repressed in the tenogenic mesenchyme of the soft palate, the Sox9 expression, and the and transcription in aponeurosis mesenchyme were almost unaffected. It implicated that the fusion of soft palate was controlled by the mesenchymal clues at the tensor veli palatini (TVP) and levator veli palatini (LVP) levels, but by the myogenic components at the palatopharyngeus (PLP) level.
PubMed: 34557486
DOI: 10.3389/fcell.2021.711334 -
European Journal of Applied Physiology Aug 2022Measurement of medial gastrocnemius (MG) tendon length using ultrasonography (US) requires the muscle-tendon junction (MTJ) to be located. Previously, the MG MTJ has...
PURPOSE
Measurement of medial gastrocnemius (MG) tendon length using ultrasonography (US) requires the muscle-tendon junction (MTJ) to be located. Previously, the MG MTJ has been tracked from different proximo-distal locations near the MTJ, which could influence estimates of tendon length change due to the different characteristics of the aponeurosis and tendon. We used US to evaluate the effect of tracking point location on MG MTJ displacement during maximal and submaximal (10, 20 and 30% of the non-injured maximal) isometric plantar flexion contractions.
METHODS
Displacement behaviour of MTJ was tracked from (1) the exact MTJ; and (2) from an insertion point of a muscle fascicle on the aponeurosis 1.3 ± 0.6 cm proximal to the MTJ, in both limbs of patients with unilateral Achilles tendon rupture (ATR) (n = 22, 4 females, 42 ± 9 years, 177 ± 9 cm, 79 ± 10 kg).
RESULTS
In the non-injured limb, displacement (1.3 ± 0.5 cm vs. 1.1 ± 0.6 cm) and strain (6.7 ± 2.8% vs. 5.8 ± 3.3%) during maximal voluntary contraction were larger when tracking a point on the aponeurosis than when tracking the MTJ (both p < 0.001). The same was true for all contraction levels, and both limbs.
CONCLUSION
Tracking a point on the aponeurosis consistently exaggerates estimates of tendon displacement, and the magnitude of this effect is contraction intensity-dependent. When quantifying displacement and strain of the Achilles tendon, the MTJ should be tracked directly, rather than tracking a surrogate point proximal to the MTJ. The latter method includes part of the aponeurosis, which due to its relative compliance, artificially increases estimates of MTJ displacement and strain.
Topics: Achilles Tendon; Aponeurosis; Female; Humans; Isometric Contraction; Muscle, Skeletal; Ultrasonography
PubMed: 35522277
DOI: 10.1007/s00421-022-04958-8 -
World Journal of Clinical Cases Oct 2021Desmoid fibroma is a rare soft tissue tumor originating from the aponeurosis, fascia, and muscle, and it is also known as aponeurotic fibroma, invasive fibroma, or...
BACKGROUND
Desmoid fibroma is a rare soft tissue tumor originating from the aponeurosis, fascia, and muscle, and it is also known as aponeurotic fibroma, invasive fibroma, or ligamentous fibroma.
AIM
To investigate the clinical and imaging features of desmoid tumors of the extremities.
METHODS
Thirteen patients with desmoid fibroma of the extremities admitted to our hospital from October 2016 to March 2021 were included. All patients underwent computed tomography (CT), magnetic resonance imaging (MRI), and pathological examination of the lesion. Data on the diameter and distribution of the lesion, the relationship between the lesion morphology and surrounding structures, MRI and CT findings, and pathological features were statistically analyzed.
RESULTS
The lesion diameter ranged from 1.7 to 8.9 cm, with an average of 5.35 ± 2.39 cm. All lesions were located in the deep muscular space, with the left and right forearm each accounting for 23.08% of cases. Among the 13 patients with desmoid fibroma of the extremities, the lesions were "patchy" in 1 case, irregular in 10, and quasi-round in 2. The boundary between the lesion and surrounding soft tissue was blurred in 10 cases, and the focus infiltrated along the tissue space and invaded the adjacent structures. Furthermore, the edge of the lesion showed "beard-like" infiltration in 2 cases; bone resorption and damage were found in 8, and bending of the bone was present in 2; the boundary of the focus was clear in 1. According to the MRI examination, the lesions were larger than 5 cm (61.54%), round or fusiform in shape (84.62%), had an unclear boundary (76.92%), showed uniform signal (69.23%), inhomogeneous enhancement (84.62%), and "root" or "claw" infiltration (69.23%). Neurovascular tract invasion was present in 30.77% of cases. CT examination showed that the desmoid tumors had slightly a lower density (69.23%), higher enhancement (61.54%), and unclear boundary (84.62%); a CT value < 50 Hu was present in 53.85% of lesions, and the enhancement was uneven in 53.85% of cases. Microscopically, fibroblasts and myofibroblasts were arranged in strands and bundles, without obvious atypia but with occasional karyotyping; cells were surrounded by collagen tissue. There were disparities in the proportion of collagen tissue in different regions, with abundant collagen tissue and few tumor cells in some areas, similar to the structure of aponeuroses or ligaments, and tumor cells invading the surrounding tissues.
CONCLUSION
Desmoid tumors of the extremities have certain imaging features on CT and MRI. The two imaging techniques can be combined to improve the diagnostic accuracy, achieve a comprehensive diagnosis of the disease in the clinical practice, and reduce the risk of missed diagnosis or misdiagnosis. In addition, their use can ensure timely diagnosis and treatment.
PubMed: 34734049
DOI: 10.12998/wjcc.v9.i29.8710 -
Revista Brasileira de Ortopedia 2018The aim of this study was to analyze the anatomic variations of the bicipital aponeurosis (BA) () and its implications for the compression of the median nerve, which is...
OBJECTIVE
The aim of this study was to analyze the anatomic variations of the bicipital aponeurosis (BA) () and its implications for the compression of the median nerve, which is positioned medially to the brachial artery, passing under the bicipital aponeurosis.
METHODS
Sixty upper limbs of 30 cadavers were dissected, 26 of which were male and four, female; of the total, 15 had been previously preserved in formalin and glycerine and 15 were dissected fresh in the Laboratory of Anatomy.
RESULTS
In 55 limbs, short and long heads of the biceps muscle contributed to the formation of the BA, and the most significant contribution was always from the short head. In three limbs, only the short head contributed to the formation of the BA. In two limbs, the BA was absent. The length of the bicipital aponeurosis from its origin to its insertion ranged from 4.5 to 6.2 cm and its width, from 0.5 to 2.6 cm. In 42 limbs, the BA was thickened; of these, in 27 it was resting directly on the median nerve, and in 17 a high insertion of the humeral head of the pronator teres muscle was found, and the muscle was interposed between the BA and the median nerve.
CONCLUSION
These results suggest that a thickened BA may be a potential factor for nerve compression, by narrowing the space through which the median nerve passes.
PubMed: 29367910
DOI: 10.1016/j.rboe.2017.11.014 -
Knee Surgery, Sports Traumatology,... May 2021The purpose of the present anatomical study was to define the exact morphology of the posterior fibulotalocalcaneal ligament complex (PFTCLC), both for a better...
PURPOSE
The purpose of the present anatomical study was to define the exact morphology of the posterior fibulotalocalcaneal ligament complex (PFTCLC), both for a better orientation and understanding of the anatomy, especially during hindfoot endoscopy.
METHODS
Twenty-three fresh frozen specimens were dissected in order to clarify the morphology of the PFTCLC.
RESULTS
In all specimens, the ligament originated from the posteromedial border of the lateral malleolus between the posterior tibiofibular ligament (superior border) and the calcaneofibular ligament (CFL), (inferior border). This origin functions as the floor for the peroneal tendon sheath. The origin of the PFTCLC can be subdivided into two parts, a superior and inferior part. The superior part forms an aponeurosis with the superior peroneal retinaculum and the lateral septum of the Achilles tendon. From this structure, two independent laminae can be identified. The inferior part of the origin has no role in the aponeurosis and ligamentous fibres run obliquely to insert in the lateral surface of the calcaneus, in the same orientation as the CFL, but slightly more posterior, which was a consistent finding in all examined specimens. The PFTCLC is maximally tensed with ankle dorsiflexion and is located within the fascia of the deep posterior compartment of the leg.
CONCLUSIONS
The PFTCLC is part of the normal anatomy of the hindfoot and therefore should be routinely recognized and partly released to achieve access to the posterior ankle anatomical pathology, relevant for hindfoot endoscopy. The origin of the ligament complex forms the floor for the peroneal tendon sheath. The superior part of the origin plays a role in the formation of an aponeurosis with the superior peroneal retinaculum and the lateral septum of the Achilles tendon.
Topics: Achilles Tendon; Ankle Joint; Aponeurosis; Cadaver; Fascia; Female; Humans; Lateral Ligament, Ankle; Male; Tarsal Bones
PubMed: 33486559
DOI: 10.1007/s00167-020-06431-5 -
BMC Musculoskeletal Disorders Jul 2020The objective of this study was to explore the relationships between claw toe deformity, peripheral neuropathy, intrinsic muscle volume, and plantar aponeurosis...
BACKGROUND
The objective of this study was to explore the relationships between claw toe deformity, peripheral neuropathy, intrinsic muscle volume, and plantar aponeurosis thickness using computed tomography (CT) images of diabetic feet in a cross-sectional analysis.
METHODS
Forty randomly-selected subjects with type 2 diabetes were selected for each of the following four groups (n = 10 per group): 1) peripheral neuropathy with claw toes, 2) peripheral neuropathy without claw toes, 3) non-neuropathic with claw toes, and 4) non-neuropathic without claw toes. The intrinsic muscles of the foot were segmented from processed CT images. Plantar aponeurosis thickness was measured in the reformatted sagittal plane at 20% of the distance from the most inferior point of the calcaneus to the most inferior point of the second metatarsal. Five measurement sites in the medial-lateral direction were utilized to fully characterize the plantar aponeurosis thickness. A linear mixed-effects analysis on the effects of peripheral neuropathy and claw toe deformity on plantar aponeurosis thickness and intrinsic muscle volume was performed.
RESULTS
Subjects with concurrent neuropathy and claw toes had thicker mean plantar aponeurosis (p < 0.006) and may have had less mean intrinsic muscle volume (p = 0.083) than the other 3 groups. The effects of neuropathy and claw toes on aponeurosis thickness were synergistic rather than additive. A similar pattern may exist for intrinsic muscle volume, but results were not as conclusive. A negative correlation was observed between plantar aponeurosis thickness and intrinsic muscle volume (R = 0.323, p < 0.001).
CONCLUSIONS
Subjects with concurrent neuropathy and claw toe deformity were associated with the smallest intrinsic foot muscle volumes and the thickest plantar aponeuroses. Intrinsic muscle atrophy and plantar aponeurosis thickening may be related to the development of claw toes in the presence of neuropathy.
Topics: Aponeurosis; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Diabetic Foot; Hammer Toe Syndrome; Humans; Peripheral Nervous System Diseases; Toes
PubMed: 32703177
DOI: 10.1186/s12891-020-03503-y