Glabrous Skin Research Articles

Double, Distally Based, Axial Pattern, Distal Perforator Thenar Flap; A Case Report

The provision of the glabrous skin with acceptable sensation is the main objective of any fingertip reconstruction. Thenar flaps can be medially based, laterally based and proximally based. However, all of them are randomly based. A distally based, axial pattern thenar flap could provide stable, like-with-like, palmar skin to the fingertip of an injured distal phalanx. We present a double, distally based axial pattern thenar flap, which we used to simultaneously reconstruct two fingers.

Superficial Zoonotic Mycoses in Humans Associated with Cats.

Dermatophytosis is a superficial fungal skin infection common in humans around the world and is one of the many zoonotic skin diseases that cat owners are at risk of contracting. This retrospective study was conducted based on a detailed analysis of the results of mycological examination and medical documentation of 56 patients diagnosed with cat-to-human dermatophytoses from January 2017 to July 2022. Zoonotic mycoses were diagnosed more frequently in young people and women. In children, lesions most often occurred in the scalp area, and in adults, in the glabrous skin area. Skin infections caused by Microsporum canis (M. canis) prevailed and were confirmed in 47 patients (83.9%). Trichophyton mentagrophytes (T. mentagrophytes) was found in nine (16.1%) patients. M. canis predominantly caused infections of the scalp, followed by lower limb infections. Hairy scalps were almost exclusively involved in children. The odds of diagnosing M. canis infection compared to T. mentagrophytes infection was significantly higher in the head than in other regions, especially among children. The positive predictive value of a direct macroscopic examination was relatively low.

Skin Reinnervation by Collateral Sprouting Following Spared Nerve Injury in Mice.

Following peripheral nerve injury, denervated tissues can be reinnervated via regeneration of injured neurons or collateral sprouting of neighboring uninjured afferents into denervated territory. While there has been substantial focus on mechanisms underlying regeneration, collateral sprouting has received less attention. Here, we used immunohistochemistry and genetic neuronal labeling to define the subtype specificity of sprouting-mediated reinnervation of plantar hindpaw skin in the mouse spared nerve injury (SNI) model, in which productive regeneration cannot occur. Following initial loss of cutaneous afferents in the tibial nerve territory, we observed progressive centripetal reinnervation by multiple subtypes of neighboring uninjured fibers into denervated glabrous and hairy plantar skin of male mice. In addition to dermal reinnervation, CGRP-expressing peptidergic fibers slowly but continuously repopulated denervated epidermis, Interestingly, GFRα2-expressing nonpeptidergic fibers exhibited a transient burst of epidermal reinnervation, followed by a trend towards regression. Presumptive sympathetic nerve fibers also sprouted into denervated territory, as did a population of myelinated TrkC lineage fibers, though the latter did so inefficiently. Conversely, rapidly adapting Aβ fiber and C fiber low threshold mechanoreceptor (LTMR) subtypes failed to exhibit convincing sprouting up to 8 weeks after nerve injury in males or females. Optogenetics and behavioral assays in male mice further demonstrated the functionality of collaterally sprouted fibers in hairy plantar skin with restoration of punctate mechanosensation without hypersensitivity. Our findings advance understanding of differential collateral sprouting among sensory neuron subpopulations and may guide strategies to promote the progression of sensory recovery or limit maladaptive sensory phenomena after peripheral nerve injury.

Modulation of Motor Cortical Inhibition and Facilitation by Touch Sensation from the Glabrous Skin of the Human Hand.

Touch sensation from the glabrous skin of the hand is essential for precisely controlling dexterous movements, yet the neural mechanisms by which tactile inputs influence motor circuits remain largely unexplored. By pairing air-puff tactile stimulation on the hand's glabrous skin with transcranial magnetic stimulation (TMS) over the primary motor cortex (M1), we examined the effects of tactile stimuli from single or multiple fingers on corticospinal excitability and M1's intracortical circuits. Our results showed that when we targeted the hand's first dorsal interosseous (FDI) muscle with TMS, homotopic (index finger) tactile stimulation, regardless of its point (fingertip or base), reduced corticospinal excitability. Conversely, heterotopic (ring finger) tactile stimulation had no such effect. Notably, stimulating all five fingers simultaneously led to a more pronounced decrease in corticospinal excitability than stimulating individual fingers. Furthermore, tactile stimulation significantly increased intracortical facilitation (ICF) and decreased long-interval intracortical inhibition (LICI) but did not affect short-interval intracortical inhibition (SICI). Considering the significant role of the primary somatosensory cortex (S1) in tactile processing, we also examined the effects of downregulating S1 excitability via continuous theta burst stimulation (cTBS) on tactile-motor interactions. Following cTBS, the inhibitory influence of tactile inputs on corticospinal excitability was diminished. Our findings highlight the spatial specificity of tactile inputs in influencing corticospinal excitability. Moreover, we suggest that tactile inputs distinctly modulate M1's excitatory and inhibitory pathways, with S1 being crucial in facilitating tactile-motor integration.

Improving cosmetic and functional outcome in case of post burn contracture of hand and fingers by using de-epithelized plantar skin graft

Background: Burn scar contractures in the fingers and hand often lead to debilitating functional and cosmetic issues. Various surgical approaches exist, but achieving optimal outcomes remains a challenge. While grafting glabrous split-thickness skin from the foot's plantar aspect is a well-established method, it remains underutilized, with conventional grafts leading to complications, especially in darker-skinned individuals. Method: This study involved 35 patients with McCauley grade II and III hand burn contractures, spanning various age groups and genders. Surgical procedures encompassed scar removal, contracture release, and plantar skin graft application. Post-operatively, patients received dressing, splinting, and physiotherapy. Donor site healing was evaluated at the 3-week mark. Results: Remarkably, all patients exhibited successful donor site healing within 3 weeks. The surgical technique effectively addressed contractures, enhancing range of motion and function. Post-operative care, featuring physiotherapy, coconut oil massages, and pressure garment use for at least 6 months, significantly contributed to post-burn hand and finger contracture management. Conclusions: De-epithelized plantar skin grafts offer a promising avenue for enhancing both aesthetics and function in individuals with post-burn hand and finger contractures. This technique minimizes complications common with traditional grafts while promoting successful donor site healing and improved range of motion. The study underscores the significance of using like-for-like reconstruction to achieve the best possible results in managing post-burn contractures.

Transient immune activation without loss of intraepidermal innervation and associated Schwann cells in patients with complex regional pain syndrome

BackgroundComplex regional pain syndrome (CRPS) develops after injury and is characterized by disproportionate pain, oedema, and functional loss. CRPS has clinical signs of neuropathy as well as neurogenic inflammation. Here, we asked whether skin biopsies could be used to differentiate the contribution of these two systems to ultimately guide therapy. To this end, the cutaneous sensory system including nerve fibres and the recently described nociceptive Schwann cells as well as the cutaneous immune system were analysed.MethodsWe systematically deep-phenotyped CRPS patients and immunolabelled glabrous skin biopsies from the affected ipsilateral and non-affected contralateral finger of 19 acute (< 12 months) and 6 chronic (> 12 months after trauma) CRPS patients as well as 25 sex- and age-matched healthy controls (HC). Murine foot pads harvested one week after sham or chronic constriction injury were immunolabelled to assess intraepidermal Schwann cells.ResultsIntraepidermal Schwann cells were detected in human skin of the finger—but their density was much lower compared to mice. Acute and chronic CRPS patients suffered from moderate to severe CRPS symptoms and corresponding pain. Most patients had CRPS type I in the warm category. Their cutaneous neuroglial complex was completely unaffected despite sensory plus signs, e.g. allodynia and hyperalgesia. Cutaneous innate sentinel immune cells, e.g. mast cells and Langerhans cells, infiltrated or proliferated ipsilaterally independently of each other—but only in acute CRPS. No additional adaptive immune cells, e.g. T cells and plasma cells, infiltrated the skin.ConclusionsDiagnostic skin punch biopsies could be used to diagnose individual pathophysiology in a very heterogenous disease like acute CRPS to guide tailored treatment in the future. Since numbers of inflammatory cells and pain did not necessarily correlate, more in-depth analysis of individual patients is necessary.

Pressure Stimuli and Spatiotemporal Illusions on the Forearm.

To design complex wearable haptic interfaces using pressure, we have to explore how we can use pressure stimuli to their full potential. Haptic illusions, such as apparent motion and apparent location, can be a part of this. If these illusions can be evoked with pressure, haptic patterns can increase in complexity without increasing the number of actuators or combining different types of actuators. We did two psychophysical experiments with pressure stimuli on the forearm using a pneumatic sleeve with multiple, individually controlled McKibben actuators. In Experiment 1, we found that spatial integration of two simultaneously presented stimuli occurred for distances up to 61 mm. In Experiment 2, we found that apparent motion can be elicited with distinct pressure stimuli over a range of temporal parameters. These results clearly show spatio-temporal integration in the somatosensory system for pressure stimuli. We discuss these findings in relation to effects found for vibration and the mechanoreceptors in the glabrous skin.

To touch or to be touched? comparing appraisal of vicarious execution and reception of interpersonal touch.

Unmyelinated C-Tactile (CT) fibres are activated by caress-like touch, eliciting a pleasant feeling that decreases for static and faster stroking. Previous studies documented this effect also for vicarious touch, hypothesising simulation mechanisms driving the perception and appreciation of observed interpersonal touch. Notably, less is known about appreciation of vicarious execution of touch, that is as referred to the one giving gentle touch. To address this issue, 53 healthy participants were asked to view and rate a series of videoclips displaying an individual being touched by another on hairy (i.e., hand dorsum) or glabrous (i.e., palm) skin sites, with touch being delivered at CT-optimal (5 cm/s) or non-CT optimal velocities (0 cm/s or 30 cm/s). Following the observation of each clip, participants were asked to rate self-referred desirability and model-referred pleasantness of vicarious touch for both executer (toucher-referred) and receiver (touchee-referred). Consistent with the CT fibres properties, for both self-referred desirability and model-referred pleasantness judgements of vicarious touch execution and reception, participants provided higher ratings for vicarious touch delivered at CT-optimal than other velocities, and when observed CT-optimal touch was delivered to the hand-dorsum compared to the palm. However, higher ratings were attributed to vicarious reception compared to execution of CT-optimal touch. Notably, individual differences in interoceptive trusting and attitude to interpersonal touch were positively correlated with, respectively, toucher- and touchee-related overall appraisal ratings of touch. These findings suggest that the appreciation of both toucher- and touchee-referred vicarious touch is specifically attuned to CT-optimal touch, even though they might rely on different neurocognitive mechanisms to understand affective information conveyed by interpersonal tactile interactions.

Donor-Site Morbidity Analysis of Thenar and Hypothenar Flap.

Background For the small glabrous skin defect, Thenar and Hypothenar skin are useful donors and they have been used as a free flap. Because of similar skin characteristics, both flaps have same indications. We will conduct comparative study for the donor morbidity of the Free thenar flap and Hypothenar free flap. Methods From January 2011 to December 2021, demographic data, characteristics of each flap, and complications using retrospective chart review were obtained. Donor outcomes of the patient, who had been followed up for more than 6 months, were measured using photographic analysis and physical examination. General pain was assessed by Numeric Rating Scale (NRS) score, neuropathic pain was assessed by Douleur Neuropathique 4 Questions (DN4) score, scar appearance was assessed by modified Vancouver Scar Scale (mVSS), and patient satisfaction was assessed on a 3-point scale. Statistical analysis was performed on the outcomes. Results Out of the 39 survey respondents, 17 patients received Free thenar flaps, and 22 patients received Hypothenar free flaps. Thenar group had higher NRS, DN4, and mVSS ( p < 0.05). The average scores for the Thenar and Hypothenar groups were 1.35 and 0.27 for NRS, 2.41 and 0.55 for DN4, and 3.12 and 1.59 for mVSS, respectively. Despite the Hypothenar group showing greater satisfaction on the 3-point scale (1.82) compared with the Thenar group (1.47), the difference was not significant ( p = 0.085). Linear regression analysis indicated that flap width did not have a notable impact on the outcome measures, and multiple linear regression analysis revealed no significant interaction between flap width and each of the outcome measures. Conclusion Despite the limited number of participants, higher donor morbidity in general pain, neuropathic pain, and scar formation was noted in the Thenar free flap compared with the Hypothenar free flap. However, no difference in overall patient satisfaction was found between the two groups.

Effects of inflammation on the properties of Nav1.8-ChR2-positive and Nav1.8-ChR2-negative afferent mechanoreceptors in the hindpaw glabrous skin of mice.

We recently used Nav1.8-ChR2 mice in which Nav1.8-expressing afferents were optogenetically tagged to classify mechanosensitive afferents into Nav1.8-ChR2-positive and Nav1.8-ChR2-negative mechanoreceptors. We found that the former were mainly high threshold mechanoreceptors (HTMRs), while the latter were low threshold mechanoreceptors (LTMRs). In the present study, we further investigated whether the properties of these mechanoreceptors were altered following tissue inflammation. Nav1.8-ChR2 mice received a subcutaneous injection of saline or Complete Freund's Adjuvant (CFA) in the hindpaws. Using the hind paw glabrous skin-tibial nerve preparation and the pressure-clamped single-fiber recordings, we found that CFA-induced hind paw inflammation lowered the mechanical threshold of many Nav1.8-ChR2-positive Aβ-fiber mechanoreceptors but heightened the mechanical threshold of many Nav1.8-ChR2-negative Aβ-fiber mechanoreceptors. Spontaneous action potential impulses were not observed in Nav1.8-ChR2-positive Aβ-fiber mechanoreceptors but occurred in Nav1.8-ChR2-negative Aβ-fiber mechanoreceptors with a lower mechanical threshold in the saline goup, and a higher mechanical threshold in the CFA group. No significant change was observed in the mechanical sensitivity of Nav1.8-ChR2-positive and Nav1.8-ChR2-negative Aδ-fiber mechanoreceptors and Nav1.8-ChR2-positive C-fiber mechanoreceptors following hind paw inflammation. Collectively, inflammation significantly altered the functional properties of both Nav1.8-ChR2-positive and Nav1.8-ChR2-negative Aβ-fiber mechanoreceptors, which may contribute to mechanical allodynia during inflammation.

Dermoscopic Findings and Assessment of Treatment Response in Patients with Tinea Incognito: A Pilot Study.

Tinea incognito presents with atypical, widespread, and recurrent lesions. Dermoscopy can aid its rapid diagnosis. This study aimed at assessing dermoscopic features and response to treatment in patients with tinea incognito. An evaluation of 62 patients with tinea of glabrous skin (Group A (cases)-31 steroid modified and Group B (controls)-31 treatment naïve) was done. Clinical, dermoscopic, and mycological evaluations were done for both groups at baseline, 2, and 4 weeks of terbinafine therapy. Clinical severity (Clinical Assessment Severity Score (CASS) and Visual Analogue Scale (VAS)) and frequency of various dermoscopic changes were compared at 0 and 4 weeks between cases and controls, using unpaired Student's t-test, Mann-Whitney U-test, and Wilcoxon signed-rank test. Baseline dermoscopic features for both groups were significantly different with respect to frequency of broken hair, bent hair, micropustules and Morse code hair. Earliest feature to resolve with treatment was micropustules at 2 weeks. Significant reduction in frequency of morphologically altered hair was evident at 4 weeks. Telangiectasia, dotted vessels, I-hair, and broken hair persisted for a longer period of time. Terbinafine for 4 weeks was an effective treatment, producing complete cure in 73% of cases and 93% of controls. Persistent dermoscopic changes at 2 weeks were found to be associated with treatment failure at 4 weeks, highlighting the role of dermoscopy in identifying patients requiring prolonged treatment. Dermoscopy can be used as a diagnostic and monitoring tool for tinea of glabrous skin.

Association of Nuclear VDR Immunoexpression with Breslow’s Thickness in Acral Melanoma

Background: Acral melanoma (AM) is a subtype of malignant melanoma (MM) that has a predilection for glabrous skin and is the most common type of melanoma among Asians. Depth of invasion is one of the prognostic factors in AM. VDR may have an association with depth of invasion in AM. However, reports from Asian patients are still lacking. The aim of this study was to explore the association between VDR immunoexpression and depth of invasion in AM patients in Bandung, Indonesia.Methods: This study was a retrospective cross-sectional study that analyzed the nuclear and cytoplasm VDR expression of melanoma cells and its association with Breslow’s thickness in patients with AM in Dr. Hasan Sadikin General Hospital Bandung. VDR immunostaining was performed on paraffin blocks. The Breslow thickness was measured using dot slide software. Chi square statistical analysis was done to determine the results.Results: Of the 30 patients, 73% had a Breslow thickness of &gt;4 mm. There was a significant inverse association between nuclear VDR immunoexpression and Breslow thickness of AM (p&lt;0.001), but not for cytoplasmic VDR immunoexpression (p=0.914). Conclusion: Low nuclear VDR immunoexpression is associated with the depth of invasion in AM. Nuclear VDR immunoexpression possibly affect progression and should be considered before administration of vitamin D therapy in AM.

Short-term cocoa bioflavanol supplementation does not improve cold-induced vasodilation in young healthy adults.

Cold-induced vasodilation (CIVD) is an oscillatory rise in blood flow to glabrous skin that occurs in cold-exposed extremities. Dietary flavanols increase bioavailable nitric oxide, a proposed mediator of CIVD through active vasodilation and/or withdrawal of sympathetic vascular smooth muscle tone. However, no studies have examined the effects of flavanol intake on extremity skin perfusion during cold exposure. We tested the hypothesis that acute and 8-day flavanol supplementation would augment CIVD during single-digit cold water immersion (CWI). Eleven healthy adults (24 ± 6years; 10M/1F) ingested cocoa flavanols (900mg/day) or caffeine- and theobromine-matched placebo for 8days in a double-blind, randomized, crossover design. On Days 1 and 8, CIVD was assessed 2h post-treatment. Subjects immersed their 3rd finger in warm water (42°C) for 15min before CWI (4°C) for 30min, during which nail bed and finger pad skin temperature were measured. Flavanol ingestion had no effect on CIVD frequency (Day 1, Flavanol: 3 ± 2 vs. Placebo: 3 ± 2; Day 8, Flavanol: 3 ± 2 vs. Placebo: 3 ± 1) or amplitude (Day 1, Flavanol: 4.3 ± 1.7 vs. Placebo: 4.9 ± 2.6°C; Day 8, Flavanol: 3.9 ± 1.9 vs. Placebo: 3.9 ± 2.0°C) in the finger pad following acute or 8-day supplementation (P > 0.05). Furthermore, average, nadir, and apex finger pad temperatures during CWI were not different between treatments on Days 1 or 8 of supplementation (P > 0.05). Similarly, no differences in CIVD parameters were observed in the nail bed following supplementation (P > 0.05). These data suggest that cocoa flavanol ingestion does not alter finger CIVD. Clinical Trial Registration Clinicaltrials.gov Identifier: NCT04359082. April 24, 2020.

Immunohistochemical detection of PIEZO1 and PIEZO2 in human digital Meissner´s corpuscles

BackgroundThe cutaneous end organ complexes or cutaneous sensory corpuscles are specialized sensory organs associated to low-threshold mechanoreceptors. Mechano-gated proteins forming a part of ion channels have been detected in both the axon and terminal glial cells of Meissner corpuscles, a specific cutaneous end organ complex in the human glabrous skin. The main candidates to mechanotransduction in Meissner corpuscles are members of the Piezo family of cationic ion channels. PIEZO2 has been detected in the axon of these sensory structures whereas no data exists about the occurrence and cell localization of PIEZO1. MethodsSkin samples (n = 18) from the palmar aspect of the distal phalanx of the first and second fingers were analysed (8 female and 10 males; age range 26 to 61 26–61 years). Double immunofluorescence for PIEZO1 and PIEZO2 together with axonal or terminal glial cell markers was captured by laser confocal microscopy, and the percentage of PIEZOs positive Meissner corpuscles was evaluated. ResultsMCs from human fingers showed variable morphology and degree of lobulation. Regarding the basic immunohistochemical profile, in all cases the axons were immunoreactive for neurofilament proteins, neuron specific enolase and synaptophysin, while the lamellar cells displayed strong S100P immunoreactivity. PIEZO1 was detected co-localizing with axonal markers, but never with terminal glial cell markers, in the 56% of Meissner corpuscles; weak but specific immunofluorescence was additionally detected in the epidermis, especially in basal keratinocytes. Similarly, PIEZO2 immunoreactivity was found restricted to the axon in the 85% of Meissner corpuscles. PIEZO2 positive Merkel cells were also regularly found. ConclusionsPIEZO1 and PIEZO2 are expressed exclusively in the axon of a subpopulation of human digital Meissner corpuscles, thus suggesting that not only PIEZO2, but also PIEZO1 may be involved in the mechanotransduction from low-threshold mechanoreceptors.

Relationship of PIEZO1 and PIEZO2 vascular expression with diabetic neuropathy.

Introduction: Diabetic distal symmetric polyneuropathy (DDSP) is the most prevalent form of diabetic peripheral neuropathy, and 25% of patients develop pain in their toes. DDSP is associated with increased cutaneous microvessel density (MVD), reduced skin blood flow, endothelial dysfunction, and impaired fluid filtration with vasodilation. The Piezo family of mechanosensitive channels is known to be involved in the control of vascular caliber by converting mechanical force into intracellular signals. Furthermore, Piezo2 is particularly involved in peripheral pain mechanisms of DDSP patients. To date, very little is known about the number, structure, and PIEZO expression in cutaneous blood vessels (BVs) of individuals with DDSP and their relation with pain and time span of diabetes. Methods and results: We studied microvessels using endothelial markers (CD34 and CD31) and smooth cell marker (α-SMA) by indirect immunohistochemical assay in sections of the glabrous skin of the toes from patients and controls. MVD was assessed through CD34 and CD31 immunoreaction. MVD determined by CD34 is higher in short-term DDSP patients (less than 15 years of evolution), regardless of pain. However, long-term DDSP patients only had increased BV density in the painful group for CD31. BVs of patients with DDSP showed structural disorganization and loss of shape. The BVs affected by painful DDSP underwent the most dramatic structural changes, showing rupture, leakage, and abundance of material that occluded the BV lumen. Moreover, BVs of DDSP patients displayed a Piezo1 slight immunoreaction, whereas painful DDSP patients showed an increase in Piezo2 immunoreaction. Discussion: These results suggest that alterations in the number, structure, and immunohistochemical profile of specific BVs can explain the vascular impairment associated with painful DDSP, as well as the temporal span of diabetes. Finally, this study points out a possible correlation between increased vascular Piezo2 immunostaining and pain and decreased vascular Piezo1 immunostaining and the development of vasodilation deficiency.

Mesenchyme governs hair follicle induction.

Tissue interactions are essential for guiding organ development and regeneration. Hair follicle formation relies on inductive signalling between two tissues, the embryonic surface epithelium and the adjacent mesenchyme. Although previous research has highlighted the hair-inducing potential of the mesenchymal component of the hair follicle - the dermal papilla and its precursor, the dermal condensate - the source and nature of the primary inductive signal before dermal condensate formation have remained elusive. Here, we performed epithelial-mesenchymal tissue recombination experiments using hair-forming back skin and glabrous plantar skin from mouse embryos to unveil that the back skin mesenchyme is inductive even before dermal condensate formation. Moreover, the naïve, unpatterned mesenchyme was sufficient to trigger hair follicle formation even in the oral epithelium. Building on previous knowledge, we explored the hair-inductive ability of the Wnt agonist R-spondin 1 and a Bmp receptor inhibitor in embryonic skin explants. Although R-spondin 1 instigated precocious placode-specific transcriptional responses, it was insufficient for hair follicle induction, either alone or in combination with Bmp receptor inhibition. Our findings pave the way for identifying the hair follicle-inducing cue.

Evaluating transient phenomena by wavelet analysis: early recovery to exercise.

Wavelet analysis (WA) provides superior time-frequency decomposition of complex signals than conventional spectral analysis tools. To illustrate its usefulness in assessing transient phenomena, we applied a custom-developed WA algorithm to laser-Doppler (LD) signals of the cutaneous microcirculation measured at glabrous (finger pulp) and nonglabrous (forearm) sites during early recovery after dynamic exercise. This phase, importantly contributing to the establishment of thermal homeostasis after exercise cessation, has not been adequately explored because of its complex, transient form. Using WA, we decomposed the LD signals measured during the baseline and early recovery into power spectra of characteristic frequency intervals corresponding to endothelial nitric oxide (NO)-dependent, neurogenic, myogenic, respiratory, and cardiac physiological influence. Assessment of relative power (RP), defined as the ratio between the median power in the frequency interval and the median power of the total spectrum, revealed that endothelial NO-dependent (5.87 early recovery; 1.53 baseline; P = 0.005; Wilcoxon signed-rank test) and respiratory (0.71 early recovery; 0.40 baseline; P = 0.001) components were significantly increased, and myogenic component (1.35 early recovery; 1.83 baseline; P = 0.02) significantly decreased during early recovery in the finger pulp. In the forearm, only the RP of the endothelial NO-dependent (1.90 early recovery; 0.94 baseline; P = 0.009) component was significantly increased. WA presents an irreplaceable tool for the assessment of transient phenomena. The relative contribution of the physiological mechanisms controlling the microcirculatory response in the early recovery phase appears to differ in glabrous and nonglabrous skin when compared with baseline; moreover, the endothelial NO-dependent influence seems to play an important role.NEW & NOTEWORTHY We address the applicability of wavelet analysis (WA) in evaluating transient phenomena on a model of early recovery to exercise, which is the only exercise-associated phase characterized by a distinct transient shape and as such cannot be assessed using conventional tools. Our WA-based algorithm provided a reliable spectral decomposition of laser-Doppler (LD) signals in early recovery, enabling us to speculate roughly on the mechanisms involved in the regulation of skin microcirculation in this phase.

Evaluation of Feasibility of Medial Plantar Artery Flap With Computed Tomography Angiography in Diabetic Patients: A Pilot Radioanatomic Study.

Background A soft tissue defect resulting from a diabetic heel ulcer can be difficult to address due to limited reconstructive options and unique local area demand. The medial plantar artery flap is ideal for heel defect coverage as it provides a thick glabrous skin with good sensory feedback. The prerequisite of medial plantar artery flap surgery is a patent medial plantar artery, which is a branch of the posterior tibial artery (PTA). Nevertheless, no feasibility study of the medial plantar artery flap in diabetic patients with vascular insufficiency has been reported so far. We conducted a pilot study with the aim of investigating the patency of the medial plantar artery in diabetic patients with suspected peripheral artery disease to determine the vascular feasibility of the medial plantar artery flap in these patients. Material and methods A pilot study was performed at Sultan Ahmad Shah Medical Centre at International Islamic University Malaysia (IIUM). A total of 15 diabetic patients with suspected vascular insufficiencywho had undergone lower limb computed tomography angiography (CTA) from January 2022 to June 2023 were included in this study. All patients were identified via the electronic record system.Lower limb CTA images were retrieved from the Radiology Information System (RIS) and Picture Archiving and Communication System (PACS) and were double-reviewed.Both the posterior tibial artery (PTA) and medial plantar artery (MPA) were assessed for their patency, and the diameter of the lumens was measured if they were patent. Bedside clinical assessments such as palpation of pulses and portable Doppler assessment were evaluated to determine whether they could serve as substitutes for computed tomography angiography (CTA) in assessing the feasibility of medial plantar artery flap using the McNemar test. Results In this study cohort, the medial plantar artery was present in 16 legs and absent in another 14 legs. The largest diameter of the medial plantar artery was 2.5mm (range 0-2.5mm). Palpation of the posterior tibial artery was not optimal for predicting the patency of the medial plantar artery, with a false positive of 21.4% and a false negative of 68.7%. Similarly, a hand-held Doppler assessment of the posterior tibial artery was also ineffective, with a false positive of 64.3% and a false negative of 18.8%. While the medial plantar artery is a continuation of the posterior tibial artery (PTA), PTA patency did not necessarily correlate with medial plantar artery patency. This was demonstrated on CTA assessment, where two legs with absent PTA still have reconstitution, resulting in patency of the medial plantar artery. Additionally, one leg with patent PTA did not have a patent medial plantar artery distally due to calcified vessels. Conclusion This is a first-of-its-kind pilot study attempting to determine the feasibility of medial plantar artery in diabetic patients with vascular insufficiency. The medial plantar artery was present in more than 50% of the investigated lower limbs, paving the way for using the medial plantar artery flap in these patients. Nevertheless, a computed tomography angiogram is essential to determine the patency of the medial plantar artery prior to the flap procedure, as palpation and hand-held Doppler were inadequate to predict the patency of the medial plantar artery in these high-risk patients.

Effects of skin moisturization on various aspects of touch showing differences with age and skin site

The human body is encompassed by a thin layer of tissue, the skin, which is heterogenous and highly specialized to protect the body and encode interactions with the external world. There is a fundamental scientific drive to understand its function, coupled with the need to preserve skin as we age, which impacts on our physiological and psychological well-being. In the present study, we aimed to define differences in touch perception between age groups and with skin cream application. We investigated touch on the finger, the forearm and cheek in younger (20–28 years, n = 22) and older (65–75 years, n = 22) females. We measured skin hydration, touch detection, finger spatial discrimination, forearm tactile pleasantness together with electrodermal activity, and perceptual ratings about cream use, skin dryness, and cosmetic habits. Glabrous finger skin became drier and touch performance was impaired with age, but these aspects were preserved in hairy skin. Skin moisturization immediately increased hydration levels, but did not significantly change touch perception. We also found that touch appreciation increased with age. We conclude that reduced finger capacity may impact self-evaluation of the skin and that long-term skin care strategies should focus on hydrating the hand to preserve touch capacities.

Comparison of Innervated and Non-innervated Free Glabrous Skin Flap Transfers for Volar Digital Defect Reconstructions - A patient-reported Outcome Study

Comparison of Innervated and Non-innervated Free Glabrous Skin Flap Transfers for Volar Digital Defect Reconstructions - A patient-reported Outcome Study