Plantar Skin Research Articles

Pitted keratolysis - a study of various clinical manifestations.

Pitted keratolysis (PK) is a common bacterial infection of skin characterized by noninflammatory superficial pits. Very few studies have focused on variations in clinical manifestations of PK. We conducted this study so that diagnosis of this treatable condition is not missed when it presents in an uncommonly perceived way. Assessment of PK patients for various sites and morphologies. A total of 30 patients with PK were assessed for various sites and morphologies. Bacterial and fungal cultures along with histopathology were performed. Of 30 patients, 24 were females. Hyperhidrosis and malodour were the most common symptoms. Interdigital interface skin of the toes was the first site affected in most patients. Plantar skin was affected in all patients with involvement of interface skin of the toes in 29 patients. Other sites affected were palms, finger web spaces, nonglabrous skin, paronychium, and nail. Other than classical pits, scaly crusted inflammatory lesions with post-inflammatory hyperpigmentation (PIH) were noted. Associated keratoderma was also reported in some patients. The presence of hyperhidrosis, malodour, and plantar lesions is consistent with previous studies. Interface skin between toes as the first site affected, involvement of toe web spaces, and associated keratoderma have been reported rarely. However, female preponderance, involvement of finger web spaces, nonglabrous skin, paronychium, nail changes, the presence of inflammation with crusting, and PIH have never been reported previously. PK can involve web spaces, nonglabrous skin, and paronychium, and can cause nail changes. The lesions can be inflammatory with crusting and PIH.

P269 Small fiber assessment by sudoscan in transthyretin familial amyloid polyneuropathy treated patients – A longitudinal study

Objective To prospectively assess small fiber involvement in Transthyretin familial amyloid polyneuropathy (TTR-FAP). Methods We studied 116 TTR-FAP Val30Met subjects (59 asymptomatic carriers, 45 tafamidis-treated, and 12 liver transplanted) at three time (t) points separated by a mean of 12.5(±4.2) and 11.5(±3.2) months between t1–t2 and t2–t3, respectively. Sural nerve action potential (SNAP), palmar and plantar sympathetic skin response (SSR) and electrochemical skin conductance (ESC) measured by Sudoscan in hands and feet were evaluated. Neuropathy Impairment Scale (NIS) and Body mass index (BMI) were recorded. Adjusted generalized linear model repeated measures was used for comparisons (level of significance set at 0.01). Results As expected, sural SNAP, plantar SSR, and feet and hands ESC, were significantly lower in tafamidis and transplanted groups (p Discussion Sudomotor function seems to decline over time among tafamidis-treated patients. Conclusions Small fiber neuropathy progression seems not to be totally halted by tafamidis treatment, as assessed with Sudoscan. Significance Sudoscan appears to be a non-invasive, easy and reproducible test to assess disease progression and treatment effectiveness in TTR-FAP.

The extended medial plantar artery (EMPA) free flap for plantar foot defects

The medial plantar artery (MPA) flap was first introduced by Mir y Mir in 1954 and used to reconstruct a heel defect. The sole of the foot is designed to bear body weight and absorb the shocks of a bipedal gait. The properties of the plantar skin and deeper tissues are therefore highly specialised, and if normal function is to be restored, it is essential to replace “like with like” which is a fundamental principle of reconstructive surgery.

Reconstrução de lesões de partes moles de pé com o uso de retalho plantar medial

ObjectiveTo study use of the medial plantar flap for reconstruction of the heel and foot. MethodThe authors share their clinical experience with the use of the medial plantar artery flap for coverage of tissue defects around the foot and heel after trauma. Twelve cases of medial plantar artery flap performed from January 2001 to December 2013 were included. ResultsOf the 12 patients, ten were male and two were female. The indications were traumatic loss of the heel pad in ten cases and the dorsal foot in two cases. All the flaps healed uneventfully without major complications, except one case with partial flap loss. The donor site was covered with a split‐thickness skin graft. The flaps had slightly inferior protective sensation compared with the normal side. ConclusionFrom these results, the authors suggest that the medial plantar artery flap is a good addition to the existing armamentarium for coverage of the foot and heel. It is versatile flap that can cover defects on the heel, over the Achilles tendon and plantar surface, as well as the dorsal foot. It provides tissue to the plantar skin with a similar texture and intact protective sensation.

G-protein coupled estrogen receptor-mediated non-genomic facilitatory effect of estrogen on cooling-induced reduction of skin blood flow in mice

An enhanced vasoconstrictor activity of cutaneous arteries participates in the reduction of skin blood flow induced by cooling stimulation. Raynaud's phenomenon, which is characterized by intense cooling-induced constriction of cutaneous arteries, is more common in women during the period from menarche to menopause. We thus investigated the effect of 17β-estradiol (E2) on cooling-induced reduction of plantar skin blood flow (PSBF) in mouse in vivo. Ovariectomized female ddY mice, anaesthetized with pentobarbital, were treated with tetrodotoxin for eliminating the sympathetic nerve tone and artificially ventilated. The PSBF was measured by laser Doppler flowmetry. Cooling air temperature around the foot from 25 to 20, 15, or 10°C decreased the PSBF in a temperature-dependent manner, which was suppressed by the specific α2C-adrenoceptor antagonist MK-912. When E2 was intravenously administered as a bolus followed by a constant infusion for 10min just before the cooling stimulation, the cooling-induced reduction of PSBF was facilitated by E2 in a dose-dependent manner. The facilitatory effect of E2 was not induced after the treatment with MK-912. Similar facilitatory effect was induced by an intravenous application of G-1, an agonist of G protein-coupled estrogen receptor (GPER, also termed GPR30). Moreover, the facilitatory effect of E2 was abolished by the GPER antagonist G15. These results suggest that acute administration of E2 leads to the facilitation of cooling-induced, α2C-adrenoceptor-mediated reduction of skin blood flow via the activation of the non-genomic estrogen receptor GPER.

Spatial-dependent mechanical properties of the heel pad by shear wave elastography

The heel pad plays an important role in gait, and its biomechanical behavior and functionality are determined by its specialized architecture and mechanical properties. The purpose of this study was to apply supersonic shear wave elastography, an ultrasound-based noninvasive modality that can quantitatively estimate the shear stiffness of the tissue, to investigate the spatial-dependent mechanical properties of the heel pad. Measurements were conducted in 40 heel pads of 20 normal participants aged between 20 and 30 years by shear wave elastography. The continuous change in local shear stiffness of the heel pad along the depth direction of the heel pad was measured. The result showed that the mechanical properties of the heel pad were highly heterogeneous but followed a simple and specific pattern that local heel pad shear stiffness was highest beneath the plantar skin and decreased continuously with increasing depth. This finding provides a better understanding of the heel pad biomechanics and basis for further investigation of the heterogeneous properties of the heel pad.

The thermoregulation of healthy individuals, overweight-obese, and diabetic from the plantar skin thermogram: a clue to predict the diabetic foot.

ABSTRACTBackground: Thermoregulation is a complex autonomic process to keep or to dissipate heat in the human body.Methods: In this work, by means of the thermogram of the plantar skin, the thermoregulation of healthy individuals, overweight–obese, and diabetic is discussed.Results: The thermograms of the plantar skin, for the healthy individuals, are: (1) symmetrical, the temperature distribution of the right foot being a mirror image of that of the left foot ; (2) the thermograms of women, on average, are 3°C colder than those of the men; and (3) the temperature distributions decrease distally from the medial longitudinal arch. The plantar skin thermograms of overweight–obese individuals show: (1) increased average temperature of both feet and for both genders; (2) no symmetry between the left and right feet thermograms; and (3) the temperature distribution is still decreasing from the medial longitudinal arch to the periphery of the foot. However, the standard deviation, for each averaged temperature of the angiosomes, shows greater uncertainty. Most thermograms of diabetic individuals show temperature increase on the plantar skin, and are mostly symmetric between left and right feet.Conclusions: An asymmetric thermogram of the plantar skin of diabetic individuals, where one foot is hotter than the other, may mean that the coldest foot is losing the capacity to communicate properly with the central nervous system and/or that vasoconstriction/vasodilatation is having problems in regulating the passing of blood through the vessels. Thus, the asymmetric thermograms of diabetic patients, and particularly those coldest regions of foot are of interest, because of the reduction of the local autonomic sensing and the lack of achieving properly the passing of the blood.

Predictive factors for skin perfusion pressure on plantar skin and diabetes complications in hemodialysis patients

Predictive factors for skin perfusion pressure on plantar skin and diabetes complications in hemodialysis patients

Different soccer stud configurations effect on running and cutting movements

The purpose of this study was to test for differences in performance and injury risks between three different outsole configuration soccer shoes on natural turf. A total of 14 experienced soccer players participated in the tests. Participants were asked to complete tasks of straight-ahead running and 45° left sidestep cutting respectively at the speed of 5.0±0.2 m/s on natural turf. They selected soccer shoes with firm ground design (FG), artificial ground design (AG) and turf cleats (TF) randomly. During 45° cut, FG showed significantly smaller peak knee flexion and greater abduction angles than TF. FG showed significant greater peak horizontal ground reaction force (GRF) and average required traction ratio compared with AG and TF. FG may offer a performance benefit on artificial turf compared to AG and TF on natural turf. However, increased knee valgus angle and decreased knee flexion angle of FG may increase knee loading and risk of anterior cruciate ligament (ACL) injury. Higher vertical average loading rate and excessive plantar pressure of FG may also resulted in calluses observed in plantar skin, forefoot pain or even metatarsal stress fracture. In summary, FG would enhance athletic performance on natural turf, but also may undertake higher risks of non-contact injuries compared with AG and TF.

A Randomized, Sham-Controlled, Double-Blind Pilot Study of Pulsed Electromagnetic Field Therapy to Evaluate Small Fiber Nerve Growth and Function and Skin Perfusion in Subjects with Painful Peripheral Diabetic Neuropathy

Purpose: The objective of this study was to determine the potential efficacy and safety of dual energy pulsed electromagnetic field therapy (PEMF) on painful distal symmetric diabetic sensorimotor polyneuropathy (DSPN). Methodology: Subjects with Type 2 diabetes and painful DSPN were randomized to receive either an active or sham PEMF device. Objective measures of efficacy (skin biopsy, nerve conduction velocity (NCV) studies, dorsal and plantar foot skin perfusion pressure (SPP) were performed prior to and following 60-days of twice daily 30 minute treatments. Patient reported outcomes included perception of pain, concomitant medication use and adverse events. Major findings: Dorsal foot SPP improved with PEMF (n=11), change from baseline=19.6 mmHg) vs. sham (n=7, change=-17.4 mmHg), p=0.03. Trends in favor of PEMF vs sham were observed for medial nerve (n=4), planter nerve (n=4) and sural nerve (n=15) onset time and amplitude (p>0.05) other than medial planter onset time (p=0.04). Although change in pain scores were similar, compliance with device use was higher in the active group compared to the sham control. The series of tests and long-term use of PEMF was well-tolerated and feasible. No device related adverse effects were recorded. Principal conclusions: Twice daily PEMF therapy was feasible, well-tolerated, and associated with trends suggesting improved nerve function and microcirculation in patients with painful DSPN. Future, large randomized controlled trials are necessary to confirm these findings and evaluate the potential longer term benefits on symptoms and pathology of DSPN.

Recovery of sympathetic nerve function after lumbar sympathectomy is slower in the hind limbs than in the torso.

Local sympathetic denervation by surgical sympathectomy is used in the treatment of lower limb ulcers and ischemia, but the restoration of cutaneous sympathetic nerve functions is less clear. This study aims to explore the recovery of cutaneous sympathetic functions after bilateral L2-4 sympathectomy. The skin temperature of the left feet, using a point monitoring thermometer, increased intraoperatively after sympathectomy. The cytoplasm of sympathetic neurons contained tyrosine hydroxylase and dopamine β-hydroxylase, visualized by immunofluorescence, indicated the accuracy of sympathectomy. Iodine starch test results suggested that the sweating function of the hind feet plantar skin decreased 2 and 7 weeks after lumbar sympathectomy but had recovered by 3 months. Immunofluorescence and western blot assay results revealed that norepinephrine and dopamine β-hydroxylase expression in the skin from the sacrococcygeal region and hind feet decreased in the sympathectomized group at 2 weeks. Transmission electron microscopy results showed that perinuclear space and axon demyelination in sympathetic cells in the L5 sympathetic trunks were found in the sympathectomized group 3 months after sympathectomy. Although sympathetic denervation occurred in the sacrococcygeal region and hind feet skin 2 weeks after lumbar sympathectomy, the skin functions recovered gradually over 7 weeks to 3 months. In conclusion, sympathetic functional recovery may account for the recurrence of hyperhidrosis after sympathectomy and the normalization of sympathetic nerve trunks after incomplete injury. The recovery of sympathetic nerve function was slower in the limbs than in the torso after bilateral L2-4 sympathectomy.

Spatial-Dependent Mechanical Properties of the Heel Pad by Shear Wave Elastography

The heel pad plays an importante role in gait, and its biomechanical behavior and functionality are determined by its specialized architecture and mechanical properties. The purpose of this study was to apply supersonic shear wave elastography, an ultrasound-based noninvasive modality that can quantitatively estimate the shear stiffness of the tissue, to investigate the spatial-dependent mechanical properties of the heel pad. Measurements were conducted in 40 heel pads of 20 normal participants aged between 20 and 30 years by shear wave elastography. The continuous change in local shear stiffness of the heel pad along the depth direction of the heel pad was measured. The result showed that the mechanical properties of heel pad were highly heterogeneous but followed a simple and specific pattern that local heel pad shear stiffness was highest beneath the plantar skin and decreased continuously with increasing depth. This finding provides a better understanding of the heel pad biomechanics and basis for further investigation of the heterogeneous properties of the heel pad.

Peripheral neuropathic changes in pachyonychia congenita.

We compared patterns of intraepidermal nerve fibers and mechanoreceptors from affected and unaffected plantar skin from patients with pachyonychia congenita (PC) and control subjects. Plantar biopsies from 10 genetically confirmed patients with PC (with a mutation in KRT6A) were performed at the ball of the foot (affected skin) and the arch (unaffected) and were compared to biopsies from corresponding locations in 10 control subjects. Tissue was processed to visualize intraepidermal nerve fibers (IENF) (PGP9.5), subsets of IENF (CGRP, substance P, tyrosine hydroxylase), myelinated nerve fiber (neurofilament H, NFH), blood vessels (CD31), Meissner corpuscles, and Merkel cells (MCs). Structures were quantified using stereology or validated quantification methods. We observed that PC-affected plantar skin had significantly lower sweat gland innervation (sweat gland nerve fiber density) and reduced numbers of Meissner corpuscles compared to PC-unaffected or anatomically matched control skin. In contrast, Merkel cell densities and blood vessel counts were higher in PC-affected skin compared to either control or PC-unaffected skin. There were no differences in myelinated nerve fiber densities, SP, or CGRP between the groups. Pressure pain thresholds in PC-affected skin were lower compared to PC-unaffected and anatomically matched control skin. Additionally, MC densities in callused plantar skin from healthy runners with callus and one subject with a nonpainful palmoplantar keratoderma (AQP5 mutation) were similar to PC-unaffected and control skin consistent with callus alone not being sufficient to increase MC number. These findings suggest that alterations in PC extend beyond keratinocytes and may provide strategies to study neuropathic pain in PC.

The TrkA receptor mediates experimental thermal hyperalgesia produced by nerve growth factor: Modulation by the p75 neurotrophin receptor

The p75 neurotrophin receptor (p75NTR) and its activation of the sphingomyelin signaling cascade are essential for mechanical hypersensitivity resulting from locally injected nerve growth factor (NGF). Here the roles of the same effectors, and of the tropomyosin receptor kinase A (TrkA) receptor, are evaluated for thermal hyperalgesia from NGF. Sensitivity of rat hind paw plantar skin to thermal stimulation after local sub-cutaneous injection of NGF (500ng) was measured by the latency for paw withdrawal (PWL) from a radiant heat source. PWL was reduced from baseline values at 0.5–22h by ∼40% from that in naïve or vehicle-injected rats, and recovered to pre-injection levels by 48h. Local pre-injection with a p75NTR blocking antibody did not affect the acute thermal hyperalgesia (0.5–3.5h) but hastened its recovery so that it had reversed to baseline by 22h. In addition, GW4869 (2mM), an inhibitor of the neutral sphingomyelinase (nSMase) that is an enzyme in the p75NTR pathway, also failed to prevent thermal hyperalgesia. However, C2-ceramide, an analog of the ceramide produced by sphingomyelinase, did cause thermal hyperalgesia. Injection of an anti-TrkA antibody known to promote dimerization and activation of that receptor, independent of NGF, also caused thermal hyperalgesia, and prevented the further reduction of PWL from subsequently injected NGF. A non-specific inhibitor of tropomyosin receptor kinases, K252a, prevented thermal hyperalgesia from NGF, but not that from the anti-TrkA antibody. These findings suggest that the TrkA receptor has a predominant role in thermal hypersensitivity induced by NGF, while p75NTR and its pathway intermediates serve a modulatory role.

Free Medial Plantar Flap Connection with a Posterior Tibial Artery Flap in Reconstruction of Fore-Mid Foot Skin Defect.

Background:Although there are many surgical treatments for covering the skin defect of the fore–mid foot, how to reconstruct the weight-bearing region remains a challenge. The weight-bearing region of the sole needs to withstand the pressure and shearing stresses of walking, so the plantar skin is anatomically different from other skins in the areas of texture, thickness, subcutaneous tissue, etc. Medial plantar flaps that are harvested from the instep region are regarded as the first choice for weight-bearing region reconstruction because of their excellent functional and aesthetic long-term result. However, when facing an extensive skin defect on a weight-bearing area such as a fore–mid foot avulsion, the application of this flap is limited because if we put the flap in a weight-bearing area of the forefoot, the set of vessels will be exposed to outside.Methods:We suggest 2 connected free flaps (posterior tibial artery flap and medial plantar flap) pedicled with 1 set of vessels. The medial plantar flap was used to cover the skin defect of the weight-bearing area in the forefoot. The dorsal skin defect of the injured foot was covered with a posterior tibial artery flap and supplied the medial plantar flap with the posterior tibial vessel. The midfoot skin defect was repaired by a full-skin grafting.Results:Long-term follow-up results showed that the shape and function of the injured limbs recovered almost entirely.Conclusion:This method of connected flaps is suitable for repairing large skin defects of the fore–mid foot.

Stimulating TRPV1 externalization and synthesis in dorsal root ganglion neurons contributes to PGE2 potentiation of TRPV1 activity and nociceptor sensitization.

Persistent peripheral sensitization contributes to chronic pain. Plasticity of nociceptive dorsal root ganglion (DRG) neurons (nociceptors) induced by pro-inflammatory mediators contributes to sensitization. Prostaglandin E2 (PGE2) enriched in injured tissues is known not only directly to sensitize DRG neurons, but also to potentiate sensitizing effects of other pain mediators such as capsaicin and its receptor transient receptor potential vanilloid-1 (TRPV1). It remains unknown whether PGE2 potentiates TRPV1 activity by stimulating its synthesis, cell surface and axonal trafficking in DRG neurons. Combined biochemical, morphological, pharmacological and behavioral approaches have been used to address this issue in both invitro and invivo models. PGE2 increased TRPV1 externalization in cultured rat DRG neurons in a time- and concentration-dependent manner, an event blocked by an inhibitor of protein synthesis or anterograde export. EP1 and EP4, but not EP2 and EP3, mediated this event. EP1 agonist-induced TRPV1 externalization was suppressed by inhibitors of CaMKII, PLC, PKC and PKCε, while EP4 agonist-induced TRPV1 externalization by inhibitors of cAMP/PKA and ERK/MAPK. Pre-exposure to PGE2 potentiated release of calcitonin gene-related peptide from cultured DRG neurons evoked by subsequent capsaicin stimulation. This event was blocked by an inhibitor of protein synthesis or export, suggesting that PGE2-induced TRPV1 synthesis and externalization is coupled to enhanced TRPV1 activity. Pre-exposure to PGE2 not only prolonged tactile allodynia evoked by subsequent capsaicin challenge, but also increased TRPV1 levels in L4-6 DRG, sciatic nerves and plantar skin. Our data indicate that facilitating TRPV1 synthesis, cell surface and axonal trafficking is a novel mechanism underlying PGE2 potentiation of TRPV1 activity.

Deimination of Human Hornerin Enhances its Processing by Calpain-1 and its Cross-Linking by Transglutaminases

Hornerin (HRNR) shares numerous features with filaggrin, a key contributor to the epidermal barrier functions. The two proteins display a related structural organization, are expressed by the granular keratinocytes as a large precursor processed by proteolysis, and are cross-linked to the cornified cell envelopes. Two main steps in the metabolism of filaggrin are its deimination and calpain-1 cleavage. Here, using ion-exchange chromatography and two-dimensional gel electrophoresis of human epidermis extracts, we determined that HRNR is deiminated invivo. Accordingly, cornified envelopes, purified from plantar and abdominal human skin, were shown to contain deiminated proteins. A recombinant form of HRNR (HRNRHis) deiminated invitro was shown to be a better substrate for transglutaminases 1 and 3 than the unmodified form. Our data also indicated that calpain-1 may be involved in the proteolytic processing of HRNR, because calpain-1 was co-located with HRNR in the cytoplasm of granular keratinocytes. Using Western blotting and mass spectrometry analysis, HRNRHis was shown to be cleaved by calpain-1 invitro, its deimination enhancing its proteolysis. In HRNR full sequence, four calpain-1 cleavage sites were identified. Altogether, these data allowed a new role to be deciphered for deimination during cornification and provided further characterization of HRNR metabolism.

Involvement of oxidative stress in increased peripheral nerve firing during spontaneous dysesthesia in a mouse model of ischemia-reperfusion

Transient ischemia-reperfusion in the hand and foot elicits spontaneous dysesthesia. However, the mechanisms by which this occurs are not completely understood. The objectives of this study were to examine peripheral neural activity related to spontaneous dysesthesia in a mouse model of hind-paw transient ischemic-reperfusion and to investigate the involvement of oxidative stress in this neural activity. The femoral artery and vein were interrupted for 10min using tourniquet pressure, before the tourniquet was removed to allow reperfusion of the hind paw. Neural activity in the saphenous nerve was recorded during both ischemia and reperfusion. In both the ischemic phase and the reperfusion phase, the frequency of saphenous nerve firing was significantly increased compared to baseline. The antioxidant agent N-acetyl-l-cysteine inhibited significantly the firing of the saphenous nerve in both the maximum and minimum activity periods during ischemia, and in the maximum activity state after reperfusion percentage inhibition being approximately 68%, 60%, and 58%, respectively. In the reperfusion phase, the production of 4-hydroxy-2-noneal, a major product of endogenous lipid peroxidation, was significantly increased in the plantar skin, and this was inhibited by N-acetyl-l-cysteine. In the ischemic phase, a similar trend was observed. These results suggest that an increase in peripheral nerve activity related to oxidative stress may be involved in the spontaneous dysesthesia induced by transient ischemia-reperfusion.

154 Why should transcriptomics and proteomics analyses performed for genodermatoses?

Genotype-phenotype correlations in genodermatoses are variable due to allelic heterogenity (mutations in a single gene causing more than one disorders) and locus heterogenity (mutations in different genes causing the same disorder). It is wiser to focus on not only mutations but also its effects on the organism. In addition to performing mutation analyses, comparative gene expression analyses (transcriptomics) and its translation to protein synthesis can not only unveil genotype-phenotype correlations but also indicate potential therapeutical targets for genodermatoses. Due to negative regulation of mTOR signaling by mutated hamartin and tuberin genes in tuberous sclerosis, topical Rapamycin shows promising results in facial angiofibromas in tuberous sclerosis patients. Recently, comparative transcriptomic and proteomic analyses of involved and uninvolved plantar skin of pachyonychia congenita reveals a new therapeutic target for troublesome plantar pain by demonstrating that increased SPRR1A expression, along with other neuropathy-related genes, directly affects plantar pain. These scarce but meaningful examples of functional genomics in genodermatoses should encourage further similar studies.

Losing touch: age-related changes in plantar skin sensitivity, lower limb cutaneous reflex strength, and postural stability in older adults

Age-related changes in the density, morphology, and physiology of plantar cutaneous receptors negatively impact the quality and quantity of balance-relevant information arising from the foot soles. Plantar perceptual sensitivity declines with age and may predict postural instability; however, alteration in lower limb cutaneous reflex strength may also explain greater instability in older adults and has yet to be investigated. We replicated the age-related decline in sensitivity by assessing monofilament and vibrotactile (30 and 250 Hz) detection thresholds near the first metatarsal head bilaterally in healthy young and older adults. We additionally applied continuous 30- and 250-Hz vibration to drive mechanically evoked reflex responses in the tibialis anterior muscle, measured via surface electromyography. To investigate potential relationships between plantar sensitivity, cutaneous reflex strength, and postural stability, we performed posturography in subjects during quiet standing without vision. Anteroposterior and mediolateral postural stability decreased with age, and increases in postural sway amplitude and frequency were significantly correlated with increases in plantar detection thresholds. With 30-Hz vibration, cutaneous reflexes were observed in 95% of young adults but in only 53% of older adults, and reflex gain, coherence, and cumulant density at 30 Hz were lower in older adults. Reflexes were not observed with 250-Hz vibration, suggesting this high-frequency cutaneous input is filtered out by motoneurons innervating tibialis anterior. Our findings have important implications for assessing the risk of balance impairment in older adults.