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Sun Y, Fede C, Zhao X, Del Felice A, Pirri C, Stecco C. Quantity and Distribution of Muscle Spindles in Animal and Human Muscles. Int J Mol Sci 2024; 25:7320. [PMID: 39000428 PMCID: PMC11242712 DOI: 10.3390/ijms25137320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Revised: 06/27/2024] [Accepted: 07/02/2024] [Indexed: 07/16/2024] Open
Abstract
Muscle spindles have unique anatomical characteristics that can be directly affected by the surrounding tissues under physiological and pathological conditions. Understanding their spatial distribution and density in different muscles is imperative to unravel the complexity of motor function. In the present study, the distribution and number/density of muscle spindles in human and animal muscles were reviewed. We identified 56 articles focusing on muscle spindle distribution; 13 articles focused on human muscles and 43 focused on animal muscles. The results demonstrate that spindles are located at the nerve entry points and along distributed vessels and they relate to the intramuscular connective tissue. Muscles' deep layers and middle segments are the main topographic distribution areas. Eleven articles on humans and thirty-three articles on animals (totaling forty-four articles) focusing on muscle spindle quantity and density were identified. Hand and head muscles, such as the pronator teres/medial pterygoid muscle/masseter/flexor digitorum, were most commonly studied in the human studies. For animals, whole-body musculature was studied. The present study summarized the spindle quantity in 77 human and 189 animal muscles. We identified well-studied muscles and any as-yet unfound data. The current data fail to clarify the relationship between quantity/density and muscle characteristics. The intricate distribution of the muscle spindles and their density and quantity throughout the body present some unique patterns or correlations, according to the current data. However, it remains unclear whether muscles with fine motor control have more muscle spindles since the study standards are inconsistent and data on numerous muscles are missing. This study provides a comprehensive and exhaustive approach for clinicians and researchers to determine muscle spindle status.
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Affiliation(s)
- Yunfeng Sun
- Padova Neuroscience Center, University of Padova, 35129 Padova, Italy; (Y.S.); (X.Z.); (A.D.F.)
| | - Caterina Fede
- Institute of Human Anatomy, Department of Neuroscience, University of Padova, 35122 Padova, Italy; (C.F.); (C.P.)
| | - Xiaoxiao Zhao
- Padova Neuroscience Center, University of Padova, 35129 Padova, Italy; (Y.S.); (X.Z.); (A.D.F.)
| | - Alessandra Del Felice
- Padova Neuroscience Center, University of Padova, 35129 Padova, Italy; (Y.S.); (X.Z.); (A.D.F.)
- Section of Neurology, Department of Neuroscience, University of Padova, 35122 Padova, Italy
| | - Carmelo Pirri
- Institute of Human Anatomy, Department of Neuroscience, University of Padova, 35122 Padova, Italy; (C.F.); (C.P.)
| | - Carla Stecco
- Institute of Human Anatomy, Department of Neuroscience, University of Padova, 35122 Padova, Italy; (C.F.); (C.P.)
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Martín-Cruces J, Cuendias P, García-Mesa Y, Cobo JL, García-Suárez O, Gaite JJ, Vega JA, Martín-Biedma B. Proprioceptive innervation of the human lips. Anat Rec (Hoboken) 2024; 307:669-676. [PMID: 37712912 DOI: 10.1002/ar.25324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 08/20/2023] [Accepted: 08/25/2023] [Indexed: 09/16/2023]
Abstract
The objective of this study was to analyze the proprioceptive innervation of human lips, especially of the orbicularis oris muscle, since it is classically accepted that facial muscles lack typical proprioceptors, that is, muscle spindles, but recently this has been doubted. Upper and lower human lips (n = 5) from non-embalmed frozen cadavers were immunostained for detection of S100 protein (to identify nerves and sensory nerve formations), myosin heavy chain (to label muscle fibers within muscle spindles), and the mechano-gated ion channel PIEZO2. No muscle spindles were found, but there was a high density of sensory nerve formations, which were morphologically heterogeneous, and in some cases resemble Ruffini-like and Pacinian sensory corpuscles. The axons of these sensory formations displayed immunoreactivity for PIEZO2. Human lip muscles lack typical proprioceptors but possess a dense sensory innervation which can serve the lip proprioception.
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Affiliation(s)
- José Martín-Cruces
- Departamento de Morfología y Biología Celular, Grupo SINPOS, Universidad de Oviedo, Oviedo, Spain
| | - Patricia Cuendias
- Departamento de Morfología y Biología Celular, Grupo SINPOS, Universidad de Oviedo, Oviedo, Spain
| | - Yolanda García-Mesa
- Departamento de Morfología y Biología Celular, Grupo SINPOS, Universidad de Oviedo, Oviedo, Spain
| | - Juan L Cobo
- Departamento de Morfología y Biología Celular, Grupo SINPOS, Universidad de Oviedo, Oviedo, Spain
- Instituto Asturiano de Odontología, Oviedo, Spain
| | - Olivia García-Suárez
- Departamento de Morfología y Biología Celular, Grupo SINPOS, Universidad de Oviedo, Oviedo, Spain
| | - Juan J Gaite
- Departamento de Morfología y Biología Celular, Grupo SINPOS, Universidad de Oviedo, Oviedo, Spain
- Unidad Dental, Clínica Universitaria de Navarra, Pamplona, Spain
| | - José A Vega
- Departamento de Morfología y Biología Celular, Grupo SINPOS, Universidad de Oviedo, Oviedo, Spain
- Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Providencia-Santiago de Chile, Chile
| | - Benjamín Martín-Biedma
- Departamento de Cirugía y Especialidades Médico-Quirúrgicas, Universidad de Santiago de Compostela, Santiago, Spain
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Omstead KM, Williams J, Weinberg SM, Marazita ML, Burrows AM. Mammalian facial muscles contain muscle spindles. Anat Rec (Hoboken) 2023; 306:2562-2571. [PMID: 36799659 DOI: 10.1002/ar.25172] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 12/20/2022] [Accepted: 01/23/2023] [Indexed: 02/18/2023]
Abstract
Muscle spindles are sensory receptors in skeletal muscle that provide information on muscle length and velocity of contraction. Previous studies noted that facial muscles lack muscle spindles, but recent reports indicate that the human platysma muscle and "buccal" muscles contain spindles. Mammalian facial muscles are active in social communication, vibrissa movement, and vocalizations, including human speech. Given these functions, we hypothesized that facial muscles contain muscle spindles, and we predicted that humans would have the greatest number, given the role our lips play in speech. We examined previously sectioned and stained (with H&E and trichrome stains) orbicularis oris (upper fibers) and zygomaticus (major) muscles across a broad phylogenetic range of mammalian species, spanning a wide distribution of body size and ecological niche, to assess the presence of muscle spindles. We also stained several sections with Sirius red to highlight the muscle spindle capsule. Our results indicate that mammalian facial muscles contain muscle spindles, supporting our hypothesis. Contrary to our prediction, though, humans (and other primates) had the lowest number of muscle spindles. We instead found that the carnivoran sample and the horse sample had the greatest number of spindles. Larger body size and nocturnality were also associated with a greater number of spindles. These results must be viewed with caution, though, as our sample size was small and there are critical mammalian taxa missing. Future work should use an expanded phylogenetic range of mammalian species to ascertain the role that phylogeny plays in muscle spindle presence and count.
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Affiliation(s)
- K Madisen Omstead
- Department of Physical Therapy, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Jade Williams
- Undergraduate Pre-Medical and Health Professions Program, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Seth M Weinberg
- Center for Craniofacial and Dental Genetics, Department of Oral and Craniofacial Sciences, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Mary L Marazita
- Center for Craniofacial and Dental Genetics, Department of Oral and Craniofacial Sciences, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Anne M Burrows
- Department of Physical Therapy, Duquesne University, Pittsburgh, Pennsylvania, USA
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Piotr M, Skieresz‐Szewczyk K, Jackowiak H, Celichowski J. Distribution and length of muscle spindles and their 3D visualisation in the medial gastrocnemius of male and female rats. J Anat 2023; 243:658-663. [PMID: 37230935 PMCID: PMC10485582 DOI: 10.1111/joa.13895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 04/27/2023] [Accepted: 05/17/2023] [Indexed: 05/27/2023] Open
Abstract
The spatial distribution of the medial gastrocnemius muscle spindles of 10 male and 10 female rats was analysed under a light microscope, and for the first time, visualised using a 3D model of the muscle. Serial cross-sections of the medial gastrocnemius muscles were separated into 10 divisions along with the proximo-distal axis. The muscle spindles of the rat medial gastrocnemius were predominantly distributed on the proximo-medial divisions of the muscle. There were no sex-related differences in the distribution of the studied receptors. A single division contained an average of 2.71 receptors for animals of both sexes. Moreover, the calculated lengths of male and female rat muscle spindles were comparable, and average lengths did not significantly differ (3.30 ± 1.47 mm for male and 3.26 ± 1.32 mm for female rats). Therefore, the present results fill gaps in recent observations concerning similarities in muscle spindle numbers between male and female animals, despite significant differences in muscle mass and size.
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Affiliation(s)
- M. Piotr
- Department of NeurobiologyPoznan University of Physical EducationPoznanPoland
| | - K. Skieresz‐Szewczyk
- Department of Histology and EmbryologyPoznan University of Life SciencesPoznanPoland
| | - H. Jackowiak
- Department of Histology and EmbryologyPoznan University of Life SciencesPoznanPoland
| | - J. Celichowski
- Department of NeurobiologyPoznan University of Physical EducationPoznanPoland
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Papaleo ED, D'Alonzo M, Fiori F, Piombino V, Falato E, Pilato F, De Liso A, Di Lazzaro V, Di Pino G. Integration of proprioception in upper limb prostheses through non-invasive strategies: a review. J Neuroeng Rehabil 2023; 20:118. [PMID: 37689701 PMCID: PMC10493033 DOI: 10.1186/s12984-023-01242-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 08/24/2023] [Indexed: 09/11/2023] Open
Abstract
Proprioception plays a key role in moving our body dexterously and effortlessly. Nevertheless, the majority of investigations evaluating the benefits of providing supplemental feedback to prosthetics users focus on delivering touch restitution. These studies evaluate the influence of touch sensation in an attempt to improve the controllability of current robotic devices. Contrarily, investigations evaluating the capabilities of proprioceptive supplemental feedback have yet to be comprehensively analyzed to the same extent, marking a major gap in knowledge within the current research climate. The non-invasive strategies employed so far to restitute proprioception are reviewed in this work. In the absence of a clearly superior strategy, approaches employing vibrotactile, electrotactile and skin-stretch stimulation achieved better and more consistent results, considering both kinesthetic and grip force information, compared with other strategies or any incidental feedback. Although emulating the richness of the physiological sensory return through artificial feedback is the primary hurdle, measuring its effects to eventually support the integration of cumbersome and energy intensive hardware into commercial prosthetic devices could represent an even greater challenge. Thus, we analyze the strengths and limitations of previous studies and discuss the possible benefits of coupling objective measures, like neurophysiological parameters, as well as measures of prosthesis embodiment and cognitive load with behavioral measures of performance. Such insights aim to provide additional and collateral outcomes to be considered in the experimental design of future investigations of proprioception restitution that could, in the end, allow researchers to gain a more detailed understanding of possibly similar behavioral results and, thus, support one strategy over another.
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Affiliation(s)
- Ermanno Donato Papaleo
- Research Unit of Neurophysiology and Neuroengineering of Human-Technology Interaction (NeXTlab), Università Campus Bio-Medico Di Roma, Via Álvaro Del Portillo 21, 00128, Rome, Italy
| | - Marco D'Alonzo
- Research Unit of Neurophysiology and Neuroengineering of Human-Technology Interaction (NeXTlab), Università Campus Bio-Medico Di Roma, Via Álvaro Del Portillo 21, 00128, Rome, Italy
| | - Francesca Fiori
- Research Unit of Neurophysiology and Neuroengineering of Human-Technology Interaction (NeXTlab), Università Campus Bio-Medico Di Roma, Via Álvaro Del Portillo 21, 00128, Rome, Italy
| | - Valeria Piombino
- Research Unit of Neurophysiology and Neuroengineering of Human-Technology Interaction (NeXTlab), Università Campus Bio-Medico Di Roma, Via Álvaro Del Portillo 21, 00128, Rome, Italy
| | - Emma Falato
- Research Unit of Neurology, Department of Medicine and Surgery, Università Campus Bio-Medico Di Roma, Via Alvaro del Portillo, 21, 00128, Rome, Italy
- Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo 200, 00128, Rome, Italy
| | - Fabio Pilato
- Research Unit of Neurology, Department of Medicine and Surgery, Università Campus Bio-Medico Di Roma, Via Alvaro del Portillo, 21, 00128, Rome, Italy
- Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo 200, 00128, Rome, Italy
| | - Alfredo De Liso
- Research Unit of Neurology, Department of Medicine and Surgery, Università Campus Bio-Medico Di Roma, Via Alvaro del Portillo, 21, 00128, Rome, Italy
- Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo 200, 00128, Rome, Italy
| | - Vincenzo Di Lazzaro
- Research Unit of Neurology, Department of Medicine and Surgery, Università Campus Bio-Medico Di Roma, Via Alvaro del Portillo, 21, 00128, Rome, Italy
- Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo 200, 00128, Rome, Italy
| | - Giovanni Di Pino
- Research Unit of Neurophysiology and Neuroengineering of Human-Technology Interaction (NeXTlab), Università Campus Bio-Medico Di Roma, Via Álvaro Del Portillo 21, 00128, Rome, Italy.
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Human Frontalis Muscle Innervation and Morphology. Plast Reconstr Surg Glob Open 2022; 10:e4200. [PMID: 35317455 PMCID: PMC8932476 DOI: 10.1097/gox.0000000000004200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 01/10/2022] [Indexed: 11/26/2022]
Abstract
Due to its clinical importance and due to a suggestion regarding the afferent innervation, the microscopic appearance of the frontalis muscle was investigated.
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May CA, Mätz-Rensing K, Aschoff D, Bramke S. Muscle spindles in the rhesus monkey platysma. J Anat 2021; 240:936-940. [PMID: 34893983 PMCID: PMC9005687 DOI: 10.1111/joa.13604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/15/2021] [Accepted: 11/22/2021] [Indexed: 11/28/2022] Open
Abstract
The platysma of the rhesus monkey consists of two parts: a platysma myoides located similar to the human platysma, and a platysma cervicale passing the dorsal cervical region and being in contact with the cheek pouch. Our investigation showed that the muscle fiber morphology was comparable in both parts. Muscle spindles were only present in regions connected to the cheek pouch and contained only nuclear chain fibers. It is tempting to speculate that they sense the filling of the cheek pouch rather than mimic activities.
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Affiliation(s)
| | - Kerstin Mätz-Rensing
- Pathology Unit, German Primate Center, Leibniz Institute für Primate Research, Göttingen, Germany
| | - Daniel Aschoff
- Pathology Unit, German Primate Center, Leibniz Institute für Primate Research, Göttingen, Germany
| | - Silvia Bramke
- Department of Anatomy, Medical Faculty Carl Gustav Carus, TU Dresden, Dresden, Germany
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Neuhuber WL, Berthoud HR. Functional anatomy of the vagus system - Emphasis on the somato-visceral interface. Auton Neurosci 2021; 236:102887. [PMID: 34634680 PMCID: PMC8627476 DOI: 10.1016/j.autneu.2021.102887] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 09/02/2021] [Accepted: 09/21/2021] [Indexed: 11/18/2022]
Abstract
Due to its pivotal role in autonomic networks, the vagus attracts continuous interest from both basic scientists and clinicians. In particular, recent advances in vagus nerve stimulation strategies and their application to pathological conditions beyond epilepsy provide a good opportunity to recall basic features of vagal peripheral and central anatomy. In addition to the "classical" vagal brainstem nuclei, i.e., dorsal motor nucleus, nucleus ambiguus and nucleus tractus solitarii, the spinal trigeminal and paratrigeminal nuclei come into play as targets of vagal afferents. On the other hand, the nucleus of the solitary tract receives and integrates not only visceral but also somatic afferents. Thus, the vagus system participates significantly in what may be defined as "somato-visceral interface".
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Affiliation(s)
- Winfried L Neuhuber
- Institute of Anatomy and Cell Biology, Friedrich-Alexander University, Krankenhausstrasse 9, Erlangen, Germany.
| | - Hans-Rudolf Berthoud
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University, 6400 Perkins Road, Baton Rouge, LA 70808, USA.
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Gartych M, Jackowiak H, Bukowska D, Celichowski J. Evaluating Sexual Dimorphism of the Muscle Spindles and Intrafusal Muscle Fibers in the Medial Gastrocnemius of Male and Female Rats. Front Neuroanat 2021; 15:734555. [PMID: 34658799 PMCID: PMC8517148 DOI: 10.3389/fnana.2021.734555] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 09/14/2021] [Indexed: 11/27/2022] Open
Abstract
This study sought to investigate the sexual dimorphism of muscle spindles in rat medial gastrocnemius muscle. The muscles were cut transversely into 5–10 and 20 μm thick serial sections and the number, density, and morphometric properties of the muscle spindles were determined. There was no significant difference (p > 0.05) in the number of muscle spindles of male (14.45 ± 2.77) and female (15.00 ± 3.13) rats. Muscle mass was 38.89% higher in males (1.08 vs. 0.66 g in females), making the density of these receptors significantly higher (p < 0.01) in females (approximately one spindle per 51.14 mg muscle mass vs. one per 79.91 mg in males). There were no significant differences between the morphometric properties of intrafusal muscle fibers or muscle spindles in male and female rats (p > 0.05): 5.16 ± 2.43 and 5.37 ± 2.27 μm for male and female intrafusal muscle fiber diameter, respectively; 5.57 ± 2.20 and 5.60 ± 2.16 μm for male and female intrafusal muscle fiber number, respectively; 25.85 ± 10.04 and 25.30 ± 9.96 μm for male and female shorter muscle spindle diameter, respectively; and 48.99 ± 20.73 and 43.97 ± 16.96 μm for male and female longer muscle spindle diameter, respectively. These findings suggest that sexual dimorphism in the muscle spindles of rat medial gastrocnemius is limited to density, which contrasts previous findings reporting differences in extrafusal fibers diameter.
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Affiliation(s)
- Magdalena Gartych
- Department of Neurobiology, Poznań University of Physical Education, Poznań, Poland
| | - Hanna Jackowiak
- Department of Histology and Embryology, Poznań University of Life Sciences, Poznań, Poland
| | - Dorota Bukowska
- Department of Neurobiology, Poznań University of Physical Education, Poznań, Poland
| | - Jan Celichowski
- Department of Neurobiology, Poznań University of Physical Education, Poznań, Poland
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May CA, Bramke S. In the human, true myocutaneous junctions of skeletal muscle fibers are limited to the face. J Anat 2021; 239:445-450. [PMID: 33641167 PMCID: PMC8273604 DOI: 10.1111/joa.13419] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 01/22/2021] [Accepted: 02/15/2021] [Indexed: 12/21/2022] Open
Abstract
Within the panniculus carnosus‐associated skeletal muscles in the human, the palmaris brevis and the platysma showed myotendinous/myofascial junctions with clear distance to the corium and the specific connection collagen type XXII. The orbicularis oris muscle, in contrast, contained bundles of striated muscle fibers reaching the corium at two distinct levels: the predominant inner ending was connected to the elastic network of the inner corium and the outer ending was within the more superficial collagen network. At both locations, the striated muscle fibers showed brush‐like cytoplasmic protrusions connecting a network which was not oriented toward the muscle fibers. Collagen type XXII was not present.
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Affiliation(s)
| | - Silvia Bramke
- Department of Anatomy, Medical Faculty Carl Gustav Carus, TU Dresden, Dresden, Germany
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11
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Platysma and the cervical superficial musculoaponeurotic system — Comparative analysis of facial crease and platysmal band development. Ann Anat 2020; 227:151414. [DOI: 10.1016/j.aanat.2019.151414] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 07/20/2019] [Accepted: 08/05/2019] [Indexed: 11/19/2022]
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Bramke S, May CA. Characterization of afferent corpuscular sensors of the human palmaris brevis muscle. J Anat 2019; 236:351-356. [PMID: 31696933 PMCID: PMC6956430 DOI: 10.1111/joa.13098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2019] [Indexed: 11/30/2022] Open
Abstract
The palmaris brevis muscle contains numerous muscle spindles to control changes of the muscle length but is devoid of tendon‐associated neuronal elements (e.g. Golgi tendon organs or Ruffini‐like corpuscles) controlling changes in muscle strength. Pacinian bodies, frequently seen in the palm of the hand, show no direct association to the muscle bundles. The observed innervation pattern of the palmaris brevis muscle points to a specific type of neuronal regulation, present in skeletal muscles with no skeletal connection.
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Affiliation(s)
- Silvia Bramke
- Department of Anatomy, Medical Faculty Carl Gustav Carus, TU Dresden, Dresden, Germany
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