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Journal of Anatomy Jun 2019The ligament of the head of femur (LHF), or ligamentum teres, is believed to provide blood supply to the head of femur and mechanical stability to the hip joint. But...
The ligament of the head of femur (LHF), or ligamentum teres, is believed to provide blood supply to the head of femur and mechanical stability to the hip joint. But these functions in the adult are often debated. The existence and distribution of neurovascular structures within the ligament are not widely documented. This study examined the blood vessels and nervous tissue within the LHF to determine whether the ligament may have a vascular and proprioceptive function at the hip joint. Histological sections from the LHF from 10 embalmed hips (six female, four male; mean age 80.4 ± 8.7 years) were cut at three levels: the foveal attachment, mid-length and its base where it attaches to the transverse acetabular ligament. Sections were stained with haematoxylin and eosin to study general tissue architecture or with von Willebrand factor and neurofilament to identify blood vessels and nervous tissue, respectively. The proportion of the ligament's cross-sectional area occupied by blood vessels was expressed as a vascularity index (VI). Nerve endings within the ligament were identified and morphologically classified. Comparisons between the VI at the three levels, or between the tissue layers of the ligament, were made using 95% confidence intervals; statistical significance was set P < 0.05. The ligament tissue comprised three distinct layers: a synovial lining with cuboidal cells, a sub-synovial zone formed of loose connective tissue and the ligament proper composed of dense collagen bundles. Patent blood vessels and nerve fibres were present both in the sub-synovial zone and the ligament proper; Pacinian corpuscles and free nerve endings were found scattered only in the sub-synovial zone. The VI of the ligament proper at the fovea was significantly higher than its middle (P = 0.01) and basal levels (P = 0.04); it was also higher than that of the sub-synovial layer (P = 0.04). The LHF has three histologically distinct zones, and blood vessels and nerves are distributed both in the sub-synovial layer and ligament proper. Higher vascularity within the ligament proper at its foveal insertion suggests a possible nutritive role of the LHF to the adult head of femur. The presence of nerves and nerve receptors indicates the ligament is involved in the perception of pain and proprioception, thereby contributing to mechanical stability of the joint.
Topics: Aged; Aged, 80 and over; Cadaver; Female; Femur; Hip Joint; Humans; Male; Round Ligament of Femur
PubMed: 30882902
DOI: 10.1111/joa.12979 -
BioRxiv : the Preprint Server For... Nov 2023Pacinian corpuscle neurons are specialized low-threshold mechanoreceptors (LTMRs) that are tuned to detect high-frequency vibration (~40-2000 Hz), however it is unclear...
Pacinian corpuscle neurons are specialized low-threshold mechanoreceptors (LTMRs) that are tuned to detect high-frequency vibration (~40-2000 Hz), however it is unclear how Pacinians and other LTMRs encode mechanical forces encountered during naturalistic behavior. Here, we developed methods to record LTMRs in awake, freely moving mice. We find that Pacinians, but not other LTMRs, encode subtle vibrations of surfaces encountered by the animal, including low-amplitude vibrations initiated over two meters away. Strikingly, Pacinians are also highly active during a wide variety of natural behaviors, including walking, grooming, digging, and climbing. Pacinians in the hindlimb are sensitive enough to be activated by forelimb- or upper-body-dominant behaviors. Finally, we find that Pacinian LTMRs have diverse tuning and sensitivity. Our findings suggest a Pacinian population code for the representation of vibro-tactile features generated by self-initiated movements and low-amplitude environmental vibrations emanating from distant locations.
PubMed: 37745531
DOI: 10.1101/2023.09.11.557225 -
Skeletal Radiology Oct 2019To provide microdissection and histological confirmation of normal Pacinian corpuscles prospectively identified using MRI in a cadaver model.
OBJECTIVE
To provide microdissection and histological confirmation of normal Pacinian corpuscles prospectively identified using MRI in a cadaver model.
METHODS
3-T MRI of a cadaveric hand specimen was performed with fiduciary markers on the skin. Based on previous descriptions, subcutaneous nodules representing presumed Pacinian corpuscles were localized with respect to the skin markers, and their sizes and depths were recorded. Focused ultrasound was performed to attempt to visualize the corpuscles. Subsequent microdissection was then performed and the presence and location of Pacinian corpuscles were recorded and compared with the findings on MRI. Histological evaluation for each identified corpuscle was performed.
RESULTS
The MRI demonstrated 11 T2-hyperintense palmar subcutaneous nodules around the second through fifth metacarpophalangeal joints. None was visible sonographically. The first eight were dissected and proved to be normal Pacinian corpuscles histologically. In sites devoid of subcutaneous nodules on MRI, subsequent dissection failed to reveal any corpuscles.
CONCLUSION
On MRI, normal Pacinian corpuscles appear as round or oval, T2-hyperintense subcutaneous nodules in the palms, clustered around the metacarpophalangeal joints, and should not be mistaken for pathological conditions.
Topics: Cadaver; Hand; Humans; Magnetic Resonance Imaging; Pacinian Corpuscles; Prospective Studies
PubMed: 31069468
DOI: 10.1007/s00256-019-03223-y -
Science Advances Dec 2020The skin covering the human palm and other specialized tactile organs contains a high density of mechanosensory corpuscles tuned to detect transient pressure and...
The skin covering the human palm and other specialized tactile organs contains a high density of mechanosensory corpuscles tuned to detect transient pressure and vibration. These corpuscles comprise a sensory afferent neuron surrounded by lamellar cells. The neuronal afferent is thought to be the mechanical sensor, whereas the function of lamellar cells is unknown. We show that lamellar cells within Meissner and Pacinian corpuscles detect tactile stimuli. We develop a preparation of bill skin from tactile-specialist ducks that permits electrophysiological recordings from lamellar cells and demonstrate that they contain mechanically gated ion channels. We show that lamellar cells from Meissner corpuscles generate mechanically evoked action potentials using R-type voltage-gated calcium channels. These findings provide the first evidence for R-type channel-dependent action potentials in non-neuronal cells and demonstrate that lamellar cells actively detect touch. We propose that Meissner and Pacinian corpuscles use neuronal and non-neuronal mechanoreception to detect mechanical signals.
PubMed: 33328243
DOI: 10.1126/sciadv.abe6393 -
Clinical Anatomy (New York, N.Y.) Jul 2018There are few data in the scientific literature about the innervation of fasciae of the hand. The present study first elucidates the density and location of nervous...
There are few data in the scientific literature about the innervation of fasciae of the hand. The present study first elucidates the density and location of nervous structures in the palmar aponeurosis and, for comparison, in the flexor retinaculum (both can be considered specializations of the deep fascia of the upper limbs). Second, it compares nonpathological with pathological palmar aponeurosis. Samples of nonpathological fascia were taken from the flexor retinaculum and palmar aponeurosis of 16 upper limbs of unembalmed cadavers. Samples of pathological palmar aponeurosis were taken from seven patients with Dupuytren's disease. All samples were stained immunohistochemically with anti-S100 and anti-tubulin antibodies, and analyzed quantitatively and qualitatively by microscopy. The palmar aponeurosis showed higher median density than the retinacula of free nerve endings (22 and 20 elements/cm , respectively), Pacinian corpuscles (2 and 0 elements/cm ) and Golgi-Mazzoni corpuscles (1.0 and 0.5 element/cm ). Some corpuscles were located at the intersections of the fibers in the three directions. Free nerve endings were denser in pathological palmar aponeurosis (38 elements/cm ). The results indicate that the palmar aponeurosis is central to proprioception of the hand and that surgery should therefore avoid injuring it. The higher density of free nerve endings in pathological samples indicates that the nervous structures are implicated in the amplified fibrosis of Dupuytren's disease. Clin. Anat. 31:677-683, 2018. © 2018 Wiley Periodicals, Inc.
Topics: Aged; Aged, 80 and over; Aponeurosis; Cross-Sectional Studies; Dupuytren Contracture; Female; Golgi-Mazzoni Corpuscles; Hand; Humans; Male; Middle Aged; Nociception; Pacinian Corpuscles; Proprioception
PubMed: 29575188
DOI: 10.1002/ca.23076 -
IEEE Transactions on Haptics 2019Recognizing and discriminating vibrotactile stimuli is an essential function of the Pacinian corpuscle. This function has been studied at length in both a computational...
Recognizing and discriminating vibrotactile stimuli is an essential function of the Pacinian corpuscle. This function has been studied at length in both a computational and an experimental setting, but the two approaches have rarely been compared, especially when the computational model has a high level of structural detail. In this paper, we explored whether the predictions of a multiscale, multiphysical computational model of the Pacinian corpuscle can predict the outcome of a corresponding psychophysical experiment. The discrimination test involved either two simple stimuli with frequency in the 160-500 Hz range, or two complex stimuli formed by combining the waveforms for a 100-Hz stimulus with a second stimulus in the 160-500 Hz range. The subjects' ability to distinguish between the simple stimuli increased as the frequency increased, a result consistent with the model predictions for the same stimuli. The model also predicted correctly that subjects would find the complex stimuli more difficult to distinguish than the simple ones and also that the discriminability of the complex stimuli would show no trend with frequency difference.
Topics: Discrimination, Psychological; Humans; Models, Theoretical; Pacinian Corpuscles; Sensory Thresholds; Touch; Touch Perception; Vibration
PubMed: 30932849
DOI: 10.1109/TOH.2019.2903500 -
Pediatric Dermatology 2023We present a rare case of Pacinian corpuscle hyperplasia (PCH) presenting with typical finger pain in a 6-year-old girl. As appendages in children are smaller than those...
We present a rare case of Pacinian corpuscle hyperplasia (PCH) presenting with typical finger pain in a 6-year-old girl. As appendages in children are smaller than those in adults, diagnostic criteria are needed for pathological confirmation of PCH in pediatric patients.
Topics: Adult; Female; Humans; Child; Pacinian Corpuscles; Hyperplasia; Pain
PubMed: 37194374
DOI: 10.1111/pde.15349 -
Skin Appendage Disorders Mar 2020This article gives an account of the commonest causes of nail pain. The acronyms GIFTED KID and FOMITE will help aid doctors in a busy clinical setting to remember the... (Review)
Review
This article gives an account of the commonest causes of nail pain. The acronyms GIFTED KID and FOMITE will help aid doctors in a busy clinical setting to remember the main causes of onychalgia, respectively, on the fingers and toes. It includes a brief overview of the clinical characteristics and focuses on the type of pain for each condition as well as the mechanisms that cause it.
PubMed: 32258050
DOI: 10.1159/000504347 -
The Journal of Hand Surgery... Jun 2023The human hand is a specialised organ for fine motion and sensation and has a relatively large representation in the homunculus. The pathway of sensation starts from...
The human hand is a specialised organ for fine motion and sensation and has a relatively large representation in the homunculus. The pathway of sensation starts from information sent by mechanoreceptors in the hand. This study reports the topography of the Pacinian corpuscle in the fingertips of a human cadaver. All 10 digits from both hands of a fresh-frozen cadaver were examined. Glabrous skin distal to the distal interphalangeal joint was harvested superficial to the periosteum including fat and subcutaneous tissue. The glabrous skin were divided into 10 sections that included five distal and five proximal sections. Modified gold chloride staining was performed. Sectioned specimens were observed under a light microscope and the density of Pacinian corpuscles was determined in each segment. The density of the corpuscles was compared between the radial/ulnar and proximal/distal segments and also between digits from the right hand versus those from the left hand. Pacinian corpuscles were observed only in the subcutaneous tissue. There was no significant difference in density of the corpuscles between the distal and proximal segments or between the right and left hands. There was a statistically significant greater density of Pacinian corpuscles on the radial segments of all digits except the thumb. There is a greater density of Pacinian corpuscles on the radial side of the human fingertip in all digits except the thumb.
Topics: Humans; Pacinian Corpuscles; Fingers; Hand; Thumb; Cadaver
PubMed: 37501544
DOI: 10.1142/S2424835523500455 -
Anatomical Record (Hoboken, N.J. : 2007) Feb 2019Chondroitin sulfate is a glycosaminoglycan involved in maintaining the morphofunctional properties of the extracellular matrix in peripheral nerves, but its distribution...
Chondroitin sulfate is a glycosaminoglycan involved in maintaining the morphofunctional properties of the extracellular matrix in peripheral nerves, but its distribution in human sensory corpuscles is unknown despite the role of extracellular matrix in mechanotransduction and axonal guidance. In this study we used immunohistochemistry to analyze the distribution of chondroitin sulfate in human cutaneous Meissner and Pacinian corpuscles. Chondroitin sulfate expression was absent from Meissner corpuscles. In Pacinian corpuscles chondroitin sulfate was found associated to a CD34 positive endoneurial-related layer, interposed between the S100 protein positive inner core cells, and the vimentin positive inner core and outer core-capsule cells. Therefore, the intermediate CD34+/chondroitin sulfate+ intermediate layer present in Pacinian corpuscles isolates the neural segment of the corpuscles (axon and inner core) from the non-neural segments (outer core and capsule). These results suggest a role of chondroitin sulfate in the proper axonal growth and guidance, within the neuronal compartment of the Pacinian corpuscles during development and reinnervation, can be hypothesized. Moreover, a role of CS in mechanotransduction cannot be ruled out. Anat Rec, 302:325-331, 2019. © 2018 Wiley Periodicals, Inc.
Topics: Adolescent; Adult; Child; Chondroitin Sulfates; Ganglia, Sensory; Humans; Mechanoreceptors; Mechanotransduction, Cellular; Middle Aged; Pacinian Corpuscles; Peripheral Nerves; Skin; Young Adult
PubMed: 30299593
DOI: 10.1002/ar.23951