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Medicina (Kaunas, Lithuania) Mar 2024This study aims to identify the precise anatomical location and therapeutic mechanisms of the KI1 acupoint (Yongquan) in relation to foot muscles and nerves, known for...
This study aims to identify the precise anatomical location and therapeutic mechanisms of the KI1 acupoint (Yongquan) in relation to foot muscles and nerves, known for treating neurological disorders and pain. Dissection of six cadavers at Chungnam National University College of Medicine examined KI1's relation to the foot's four-layer structure. The KI1 acupoint was located in the superficial and deep layers of the plantar foot, adjacent to significant nerves like the medial and lateral plantar nerves. Differences in the acupoint's exact location between genders were noted, reflecting variances in foot morphology. KI1 acupuncture was found to stimulate the muscle spindles and nerve fibers essential for balance and bipedal locomotion. This stimulation may enhance sensory feedback, potentially improving cognitive functions and balance control. This anatomical insight into KI1 acupuncture underpins its potential in neurological therapies and pain management.
Topics: Humans; Acupuncture Points; Male; Female; Foot; Cadaver; Acupuncture Therapy; Tibial Nerve; Aged
PubMed: 38674181
DOI: 10.3390/medicina60040535 -
Journal of Foot and Ankle Research Nov 2023The heel is a complex anatomical region and is very often the source of pain complaints. The medial heel contains a number of structures, capable of compressing the main...
BACKGROUND
The heel is a complex anatomical region and is very often the source of pain complaints. The medial heel contains a number of structures, capable of compressing the main nerves of the region and knowing its anatomical topography is mandatory. The purpose of this work is to evaluate if tibial nerve (TN) and its main branches relate to the main anatomical landmarks of the ankle's medial side and if so, do they have a regular path after emerging from TN.
METHODS
The distal part of the legs, ankles and feet of 12 Thiel embalmed cadavers were dissected. The pattern of the branches of the TN was registered and the measurements were performed according to the Dellon-McKinnon malleolar-calcaneal line (DML) and the Heimkes Triangle (HT).
RESULTS
The TN divided proximal to DML in 87.5%, on top of the DML in 12,5% and distal in none of the feet. The Baxter's nerve (BN) originated proximally in 50%, on top of the DML in 12,5% and distally in 37.5% of the cases. There was a strong and significant correlation between the length of DML and the distance from the center of the medial malleolus (MM) to the lateral plantar nerve (LPN), medial plantar (MPN) nerve, BN and Medial Calcaneal Nerve (MCN) (ρ: 0.910, 0.866, 0.970 and 0.762 respectively, p < 0.001).
CONCLUSIONS
In our sample the TN divides distal to DML in none of the cases. We also report a strong association between ankle size and the distribution of the MPN, LPN, BN and MCN. We hypothesize that location of these branches on the medial side of the ankle could be more predictable if we take into consideration the distance between the MM and the medial process of the calcaneal tuberosity.
Topics: Humans; Tarsal Tunnel Syndrome; Ankle; Foot; Calcaneus; Heel
PubMed: 37957735
DOI: 10.1186/s13047-023-00682-4 -
BMC Infectious Diseases Jan 2024Leprosy is a chronic infectious disease caused by Mycobacterium leprae, predominantly affecting the peripheral nerves, resulting in sensory and motor deficits in the...
BACKGROUND
Leprosy is a chronic infectious disease caused by Mycobacterium leprae, predominantly affecting the peripheral nerves, resulting in sensory and motor deficits in the feet. Foot ulcers and imbalances are frequent manifestations in leprosy, often correlating with diminished sensitivity. While clinical scales and monofilament esthesiometers are conventionally utilized to evaluate foot sensitivity and balance in these patients, their discriminatory power is limited and their effectiveness is greatly dependent on the examiner's proficiency. In contrast, baropodometry and posturography offer a more comprehensive evaluation, aiming to preempt potential damage events. This study aimed was to assess the correlation between baropodometry and force plate measurements in leprosy patients and control participants, to improve the prevention and treatment of foot ulcers and complications associated with leprosy.
METHODOLOGY
This cross-sectional study was conducted during 2022 and enrolled 39 participants (22 patients with multibacillary leprosy and 17 non-leprosy controls). Demographic data were collected, and a monofilament esthesiometer was used to assess sensory deficits. In addition, physical examinations and balance and plantar pressure tests were conducted. The Student's t-test was used to compare mean and maximum plantar pressures between groups. For most COP variables, a Mann-Whitney Wilcoxon test was used, except for AP amplitude which was analyzed with the Student's t-test due to its normal distribution. The relationship between foot pressure and balance control was assessed using Spearman's correlation, focusing on areas with significant pressure differences between groups.
PRINCIPAL FINDINGS
Leprosy patients showed increased pressure in forefoot areas (T1, M1, T2-T5, and M2) and decreased pressure in hindfoot regions (MH and LH) compared to controls. These patients also displayed higher AP and ML amplitudes, suggesting poorer COP control. Correlation analyses between the two groups revealed that foot plantar pressures significantly impact balance control. Specifically, increased T1 region pressures correlated with greater sway in balance tasks, while decreased MH region pressures were linked to reduced COP control.
CONCLUSIONS/SIGNIFICANCE
The findings suggest a joint disturbance of plantar pressure distribution and static balance control in leprosy patients. These alterations may increase the risk of tissue injuries, including calluses and deformities, as well as falls.
Topics: Humans; Cross-Sectional Studies; Diabetic Foot; Leprosy, Multibacillary; Foot; Lower Extremity
PubMed: 38267905
DOI: 10.1186/s12879-023-08749-0 -
Frontiers in Neuroscience 2023Individuals with lower limb loss experience an increased risk of falls partly due to the lack of sensory feedback from their missing foot. It is possible to restore...
INTRODUCTION
Individuals with lower limb loss experience an increased risk of falls partly due to the lack of sensory feedback from their missing foot. It is possible to restore plantar sensation perceived as originating from the missing foot by directly interfacing with the peripheral nerves remaining in the residual limb, which in turn has shown promise in improving gait and balance. However, it is yet unclear how these electrically elicited plantar sensation are integrated into the body's natural sensorimotor control reflexes. Historically, the H-reflex has been used as a model for investigating sensorimotor control. Within the spinal cord, an array of inputs, including plantar cutaneous sensation, are integrated to produce inhibitory and excitatory effects on the H-reflex.
METHODS
In this study, we characterized the interplay between electrically elicited plantar sensations and this intrinsic reflex mechanism. Participants adopted postures mimicking specific phases of the gait cycle. During each posture, we electrically elicited plantar sensation, and subsequently the H-reflex was evoked both in the presence and absence of these sensations.
RESULTS
Our findings indicated that electrically elicited plantar sensations did not significantly alter the H-reflex excitability across any of the adopted postures.
CONCLUSION
This suggests that individuals with lower limb loss can directly benefit from electrically elicited plantar sensation during walking without disrupting the existing sensory signaling pathways that modulate reflex responses.
PubMed: 37817801
DOI: 10.3389/fnins.2023.1276308 -
Military Medical Research Apr 2024The channel-forming protein Pannexin1 (Panx1) has been implicated in both human studies and animal models of chronic pain, but the underlying mechanisms remain...
BACKGROUND
The channel-forming protein Pannexin1 (Panx1) has been implicated in both human studies and animal models of chronic pain, but the underlying mechanisms remain incompletely understood.
METHODS
Wild-type (WT, n = 24), global Panx1 KO (n = 24), neuron-specific Panx1 KO (n = 20), and glia-specific Panx1 KO (n = 20) mice were used in this study at Albert Einstein College of Medicine. The von Frey test was used to quantify pain sensitivity in these mice following complete Freund's adjuvant (CFA) injection (7, 14, and 21 d). The qRT-PCR was employed to measure mRNA levels of Panx1, Panx2, Panx3, Cx43, Calhm1, and β-catenin. Laser scanning confocal microscopy imaging, Sholl analysis, and electrophysiology were utilized to evaluate the impact of Panx1 on neuronal excitability and morphology in Neuro2a and dorsal root ganglion neurons (DRGNs) in which Panx1 expression or function was manipulated. Ethidium bromide (EtBr) dye uptake assay and calcium imaging were employed to investigate the role of Panx1 in adenosine triphosphate (ATP) sensitivity. β-galactosidase (β-gal) staining was applied to determine the relative cellular expression levels of Panx1 in trigeminal ganglia (TG) and DRG of transgenic mice.
RESULTS
Global or neuron-specific Panx1 deletion markedly decreased pain thresholds after CFA stimuli (7, 14, and 21 d; P < 0.01 vs. WT group), indicating that Panx1 was positively correlated with pain sensitivity. In Neuro2a, global Panx1 deletion dramatically reduced neurite extension and inward currents compared to the WT group (P < 0.05), revealing that Panx1 enhanced neurogenesis and excitability. Similarly, global Panx1 deletion significantly suppressed Wnt/β-catenin dependent DRG neurogenesis following 5 d of nerve growth factor (NGF) treatment (P < 0.01 vs. WT group). Moreover, Panx1 channels enhanced DRG neuron response to ATP after CFA injection (P < 0.01 vs. Panx1 KO group). Furthermore, ATP release increased Ca responses in DRGNs and satellite glial cells surrounding them following 7 d of CFA treatment (P < 0.01 vs. Panx1 KO group), suggesting that Panx1 in glia also impacts exaggerated neuronal excitability. Interestingly, neuron-specific Panx1 deletion was found to markedly reduce differentiation in cultured DRGNs, as evidenced by stunted neurite outgrowth (P < 0.05 vs. Panx1 KO group; P < 0.01 vs. WT group or GFAP-Cre group), blunted activation of Wnt/β-catenin signaling (P < 0.01 vs. WT, Panx1 KO and GFAP-Cre groups), and diminished cell excitability (P < 0.01 vs. GFAP-Cre group) and response to ATP stimulation (P < 0.01 vs. WT group). Analysis of β-gal staining showed that cellular expression levels of Panx1 in neurons are significantly higher (2.5-fold increase) in the DRG than in the TG.
CONCLUSIONS
The present study revealed that neuronal Panx1 is a prominent driver of peripheral sensitivity in the setting of inflammatory pain through cell-autonomous effects on neuronal excitability. This hyperexcitability dependence on neuronal Panx1 contrasts with inflammatory orofacial pain, where similar studies revealed a prominent role for glial Panx1. The apparent differences in Panx1 expression in neuronal and non-neuronal TG and DRG cells are likely responsible for the distinct impact of these cell types in the two pain models.
Topics: Animals; Connexins; Mice; Nerve Tissue Proteins; Disease Models, Animal; Pain; Neurons; Inflammation; Mice, Knockout; Male
PubMed: 38685116
DOI: 10.1186/s40779-024-00525-8 -
Anatomy & Cell Biology Jun 2023In the foot, the lumbricals flex the metatarsophalangeal joints and extend the interphalangeal joints. The lumbricals are known to be affected in neuropathies. It is not...
In the foot, the lumbricals flex the metatarsophalangeal joints and extend the interphalangeal joints. The lumbricals are known to be affected in neuropathies. It is not known whether they may degenerate in normal individuals. Here, we report our findings of isolated degenerated lumbricals in seemingly normal feet of two cadavers. We explored lumbricals in 20 male and 8 female cadavers that were 60-80 years of age at the time of death. As part of routine dissection, we exposed the tendons of the flexor digitorum longus and the lumbricals. From the degenerated lumbricals, we took some tissue for paraffin-embedding, sectioning, and staining by hematoxylin and eosin, and Masson's trichrome technique. Of the 224 lumbricals studied, we found four apparently degenerated lumbricals in two male cadavers. In the first, the 2nd and 4th lumbricals in the left foot and the 2nd in the right foot were degenerated. In the second, the right 4th lumbrical was degenerated. Microscopically, the degenerated tissue was made of bundles of collagen. The lumbricals may have degenerated due to compression of their nerve supply. We cannot comment on whether the functionality of the feet were affected by these isolated degeneration of the lumbricals.
PubMed: 36894494
DOI: 10.5115/acb.22.225 -
Cureus Oct 2023Mechanisms of sciatic nerve injury include gunshot injury, sharps injury, injection injury, contusion, femoral fracture injury, and iatrogenic injury due to fracture...
OBJECTIVE
Mechanisms of sciatic nerve injury include gunshot injury, sharps injury, injection injury, contusion, femoral fracture injury, and iatrogenic injury due to fracture surgery. Regardless of the type of injury, patients undergoing sciatic nerve repair have poor motor and sensory outcomes. In this study, we compared the late outcomes of a group of patients in whom the author performed an early end-to-end anastomosis for sciatic nerve sharps injury and another group of patients with a similar injury who were not operated on but left to natural history.
METHODS
The sciatic nerve, comprising two primary divisions with distinct muscle innervations, was subject to separate examinations. Group 1 (n=10, study group) underwent tibial division anastomosis, while Group 2 (n=12, control group) received no surgical intervention involving the tibial division. Similarly, Group 3 (n=11, study group) underwent peroneal division anastomosis, while Group 4 (n=14, control group) encompassed subgroups that did not undergo peroneal division surgery.
RESULTS
In Group 1, the rate of gain in plantar flexion muscle strength was significantly higher (p < 0.05) compared to Group 2. Furthermore, the sensory examination gain level ratio within the tibial domain was significantly greater (p < 0.05) in Group 1 than in Group 2. Additionally, Group 1 exhibited a significantly higher rate (p < 0.05) of detection of regeneration and reinnervation findings in electromyography (EMG) compared to Group 2.
CONCLUSION
When evaluating the long-term outcomes following early end-to-end anastomoses of the sciatic nerve, it becomes evident that while significant improvements are observed when compared to individuals without anastomosis, the positive impact of surgical interventions on motor and sensory gains in daily life remains limited. Nevertheless, we contend that early surgical intervention holds potential advantages in terms of patient management.
PubMed: 38021623
DOI: 10.7759/cureus.47101 -
Scientific Reports Oct 2023Irrespective of the exceptional adaptation of dromedaries to harsh environmental conditions, they remain highly susceptible to joint lameness resulting from a range of...
Irrespective of the exceptional adaptation of dromedaries to harsh environmental conditions, they remain highly susceptible to joint lameness resulting from a range of diverse factors and conditions. The joints most often affected by traumatic osteoarthritis in dromedaries are the metacarpophalangeal and metatarsophalangeal joints. A comprehensive understanding of joint anatomy and topography of the dromedary is required to perform arthrocentesis correctly on affected joints. Forty-two distal limbs were taken from 28 camels and studied by gross dissection, casting, ultrasonography, and computed tomography (CT). Representative three-dimensional models of the joint cavities, recesses, and pouches were obtained using different casting agents. This study provides a detailed description of dorsally, axially, and abaxially positioned joint recesses, as well as palmar/plantar positioned joint pouches. The safety and feasibility of the different arthrocentesis approaches were evaluated. The traditional dorsal arthrocentesis approach of the metacarpophalangeal, metatarsophalangeal, proximal interphalangeal, and distal interphalangeal joints, has limitations due to the risk of damaging the tendon structures and articular cartilage, which can lead to joint degeneration. A lateral arthrocentesis approach via the proximal palmar/plantar pouches of the metacarpophalangeal/metatarsophalangeal and proximal interphalangeal joints is recommended. This approach eliminates the potential needle injury to the articulating joint cartilage and other surrounding joint structures, such as tendons, blood vessels, and nerves.
Topics: Animals; Camelus; Arthrocentesis; Forelimb; Joints; Cartilage, Articular; Metatarsophalangeal Joint
PubMed: 37833397
DOI: 10.1038/s41598-023-44391-1 -
Indian Journal of Pharmacology 2023The goal of the research is to investigate the protocatechuic acid (PCA) potential action, a phenolic acid derivative, on pain induced by neuropathy and to determine its...
OBJECTIVES
The goal of the research is to investigate the protocatechuic acid (PCA) potential action, a phenolic acid derivative, on pain induced by neuropathy and to determine its efficacy on activation of K type channels and A receptors.
MATERIALS AND METHODS
Neuropathic pain by cause of sciatic nerve damage was induced in Sprague-Dawley rats. Anti-allodynic and anti-hyperalgesic effects were evaluated with von Frey apparatus and Hargreave's plantar test apparatus, respectively. The effects of PCA at the doses of 75, 150 and 300 mg/kg, carbamazepine at the doses of 50 and 100 mg/kg, combination of low effective doses of PCA and carbamazepine were tested. Pretreatments 3 μg/kg DPCPX as adenosine A receptor antagonist and 60.7 nmol glibenclamide as K channel blocker were applied for mechanistic studies.
RESULTS
PCA showed anti-allodynic and anti-hyperalgesic effects without impairing locomotor activity. In addition, the combination treatment was found to be more effective than the separate individual treatments of drugs. K channel activation related with A receptor stimulation makes a significant contribution to the anti-allodynia and anti-hyperalgesia induced by PCA.
CONCLUSIONS
It can be said that PCA has similar effects with carbamazepine, which is used in clinical practice, and that PCA can take place as an adjuvant drug in neuropathic pain with the combination group. In addition, it is seen that the undesirable effects that drugs can cause alone can be avoided and a more effective treatment potential can be created with multiple mechanisms.
Topics: Rats; Animals; Rats, Sprague-Dawley; Neuralgia; Hyperalgesia; Carbamazepine; Adenosine Triphosphate
PubMed: 37929410
DOI: 10.4103/ijp.ijp_364_21