Measurement of skin elasticity on the foot

Ultrasonographic evaluation of the masseter muscle in patients with temporomandibular joint degeneration

Purpose

Sonographic elastography can be used to evaluate the hardness of muscle tissue through the application of compression. Strain elastography gauges hardness through the comparison of echo sets before and after compression. This study utilized ultrasonography to measure the thickness and hardness of the masseter muscle in individuals with temporomandibular joint (TMJ) osteoarthritis.

Materials and Methods

This study included 40 patients who presented with joint pain and were diagnosed with TMJ osteoarthritis via diagnostic cone-beam computed tomography, along with 40 healthy individuals. The thickness and hardness of each individual's masseter muscle were evaluated both at rest and at maximum bite using ultrasonography. The Mann-Whitney U test and the chi-square test were employed for statistical analysis, with the significance level set at P<0.05.

Results

The mean thickness of the resting masseter muscle was 0.91 cm in patients with osteoarthritis, versus 1.00 cm in healthy individuals. The mean thickness of the masseter muscle at maximum bite was 1.28 cm in osteoarthritis patients and 1.36 cm in healthy individuals. The mean masseter elasticity index ratio at maximum bite was 4.51 in patients with osteoarthritis and 3.16 in healthy controls. Significant differences were observed between patients with osteoarthritis and healthy controls in both the masseter muscle thickness and the masseter elasticity index ratio, at rest and at maximum bite (P<0.05).

Conclusion

The thickness of the masseter muscle in patients with TMJ osteoarthritis was less than that in healthy controls. Additionally, the hardness of the masseter muscle was greater in patients with TMJ osteoarthritis.

Photoprotective and Antiaging Effects of a Standardized Red Orange (Citrus sinensis (L.) Osbeck) Extract in Asian and Caucasian Subjects: A Randomized, Double-Blind, Controlled Study

The increase in solar ultraviolet radiation (UVR) that reaches the Earth’s surface should make us reflect on the need to develop new approaches in protecting the skin from UVR exposure. The present study aims to evaluate the photoprotective and antiaging efficacy of a red orange extract (100 mg/day) in both Asian and Caucasian subjects. A randomized, double-blind, controlled study was carried out in 110 Asian and Caucasian subjects. Product efficacy was measured as follows: (1) the photoprotective effect was measured by the minimal erythema dose (MED) assessment; (2) the efficacy in decreasing the UVA+B-induced skin redness was measured by colorimetry; (3) the antioxidant efficacy was measured by the ferric-reducing antioxidant power (FRAP) and the malondialdehyde (MDA) assay; and (4) skin moisturization, skin elasticity, skin radiance, the intensity of melanin staining, transepidermal water loss (TEWL), and wrinkles were measured to assess the antiaging efficacy. The intake of the product for 56 days was effective in improving the skin reaction to UV exposure; in increasing the skin antioxidant capacity as well as in decreasing UVA-induced lipid peroxidation; in increasing the skin moisturization, skin elasticity, and skin radiance; and in decreasing TEWL, the intensity of melanin staining inside dark spots, and wrinkle depth. Our results suggest that the test product is effective in counteracting both the harmful effects of UVR exposure and aging signs.

Development of the infant foot as a load bearing structure: study protocol for a longitudinal evaluation (the Small Steps study)

BACKGROUND

An improved understanding of the structural and functional development of the paediatric foot is fundamental to a strong theoretical framework for health professionals and scientists. An infant's transition from sitting, through crawling and cruising, to walking is when the structures and function of the foot must adapt to bearing load. The adaptation of skin and other hard and soft tissue, and foot and gait biomechanics, during this time is poorly understood. This is because data characterising the foot tissue and loading pre-walking onset does not exist. Of the existing kinematic and plantar pressure data, few studies have collected data which reflects the real-life activities of infants with modern equipment.

METHODS

This is a longitudinal study and part of the Great Foundations Initiative, a collaborative project between the University of Brighton and the University of Salford, which is seeking to improve foot health in children. Two cohorts of 50 infants will be recruited at the two sites (University of Brighton, Eastbourne, UK and University of Salford, Salford, UK). Infants will be recruited when they first reach for their feet and attend four laboratory visits at milestones related to foot loading, with experienced independent walking being the final milestone. Data collection will include tissue characteristics (skin thickness, texture, elasticity, pH and tendon thickness and cross-sectional area), plantar pressures and kinematics captured during real world locomotion tasks.

DISCUSSION

This study will provide a database characterising the development of the infant foot as it becomes a weight bearing structure. The data will allow effective comparison and quantification of changes in structure and function due to maturation and loading by measuring pre and post established walking. Additional variables which impact on the development of the foot (gender, ethnicity and body weight) will also be factored into our analysis. This will help us to advance understanding of the determinants of foot development in early childhood.

A Solution-Processable, Omnidirectionally Stretchable, and High-Pressure-Sensitive Piezoresistive Device

The development of omnidirectionally stretchable pressure sensors with high performance without stretching-induced interference has been hampered by many challenges. Herein, an omnidirectionally stretchable piezoresistive pressure-sensing device is demonstrated by combining an omniaxially stretchable substrate with a 3D micropattern array and solution-printing of electrode and piezoresistive materials. A unique substrate structural design and materials mean that devices that are highly sensitive are rendered, with a stable out-of-plane pressure response to both static (sensitivity of 0.5 kPa^-1 and limit of detection of 28 Pa) and dynamic pressures and the minimized in-plane stretching responsiveness (a small strain gauge factor of 0.17), achieved through efficient strain absorption of the electrode and sensing materials. The device can detect human-body tremors, as well as measure the relative elastic properties of human skin. The omnidirectionally stretchable pressure sensor with a high pressure sensitivity and minimal stretch-responsiveness yields great potential to skin-attachable wearable electronics, human-machine interfaces, and soft robotics applications.

Comparative Skin Evaluation After Split-Thickness Skin Grafts Using 2 Different Acellular Dermal Matrices to Cover Composite Forearm Defects

PURPOSE

The combination of acellular dermal matrix (ADM) and split-thickness skin graft (STSG) has been widely adopted to overcome functional and cosmetic limitations of conventional STSG. In this study, we evaluated the efficacy of this combination using 2 types of ADM: cadaveric acellular dermal matrix (CDM) and bovine acellular dermal matrix (BDM).

METHODS

We recruited 72 patients undergoing autologous STSG to cover radial forearm free flap donor sites. They were included in 1 of 3 therapeutic groups: group 1, STSG using CDM (n = 29); group 2, STSG using BDM (n = 20); and group 3, STSG only (n = 23). Functional skin values for skin elasticity, humidification, transepidermal water loss, and color were determined. Values were compared between graft sites and adjacent normal (control) skin, and between grafted areas of each group.

RESULTS

All skin defects were successfully reconstructed without graft loss. Groups 1 and 2 demonstrated better elasticity than did group 3, based on the analysis using the ratio of grafted area to control. Grafted areas in all 3 groups exhibited less moisture than did control normal skin. There was less transepidermal water loss in group 1 than in group 3, which implied that CDM application had better barrier capacity against water evaporation. Graft sites of groups 1 and 3 exhibited darker and redder color compared with control areas.

CONCLUSIONS

Composite forearm defects were successfully restored and exhibited acceptable quality after treatment with an ADM plus STSG. Applying either CDM or BDM under a STSG was a suitable procedure, as verified by objective measurements. Elasticity was well preserved in CDM and BDM groups. However, both ADMs revealed functional impairment of humidification.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Skin characteristics: normative data for elasticity, erythema, melanin, and thickness at 16 different anatomical locations

BACKGROUND

The clinical use of non-invasive instrumentation to evaluate skin characteristics for diagnostic purposes and to evaluate treatment outcomes has become more prevalent. The purpose of this study was to generate normative data for skin elasticity, erythema (vascularity), melanin (pigmentation), and thickness across a broad age range at a wide variety of anatomical locations using the Cutometer(®) (6 mm probe), Mexameter(®) , and high-frequency ultrasound in a healthy adult sample.

METHODS

We measured skin characteristics of 241 healthy participants who were stratified according to age and gender. Sixteen different anatomical locations were measured using the Cutometer(®) for maximum skin deformation, gross elasticity, and biological elasticity, the Mexameter(®) for erythema and melanin, and high-frequency ultrasound for skin thickness. Standardized measurement procedures were applied for all participants.

RESULTS

The means and standard deviations for each measured skin characteristic for females and males across five different age groups (20-29, 30-39, 40-49, 50-59, 60-69, and 70-85 years old) are presented. As previously described, there were variations in skin characteristics across age groups, anatomical locations, and between females and males highlighting the need to use site specific, age and gender matched data when comparing skin characteristics.

CONCLUSION

The reported data provides normative data stratified by anatomical location, age, and gender that can be used by clinicians and researchers to objectively determine whether patients' skin characteristics vary significantly from healthy subjects.

The reliability of non-invasive biophysical outcome measures for evaluating normal and hyperkeratotic foot skin

Background

Hyperkeratosis of foot skin is a common skin problem affecting people of different ages. The clinical presentation of this condition can range from dry flaky skin, which can lead to fissures, to hard callused skin which is often painful and debilitating. The purpose of this study was to test the reliability of certain non-invasive skin measurement devices on foot skin in normal and hyperkeratotic states, with a view to confirming their use as quantitative outcome measures in future clinical trials.

Methods

Twelve healthy adult participants with a range of foot skin conditions (xerotic skin, heel fissures and plantar calluses) were recruited to the study. Measurements of normal and hyperkeratotic skin sites were taken using the following devices: Corneometer® CM 825, Cutometer® 580 MPA, Reviscometer® RVM 600, Visioline® VL 650 Quantiride® and Visioscan® VC 98, by two investigators on two consecutive days. The intra and inter rater reliability and standard error of measurement for each device was calculated.

Results

The data revealed the majority of the devices to be reliable measurement tools for normal and hyperkeratotic foot skin (ICC values > 0.6). The surface evaluation parameters for skin: SEsc and SEsm have greater reliability compared to the SEr measure. The Cutometer® is sensitive to soft tissue movement within the probe, therefore measurement of plantar soft tissue areas should be approached with caution. Reviscometer® measures on callused skin demonstrated an unusually high degree of error.

Conclusions

These results confirm the intra and inter rater reliability of the Corneometer®, Cutometer®, Visioline® and Visioscan® in quantifying specific foot skin biophysical properties.

Constitutive formulation and numerical analysis of the biomechanical behaviour of forefoot plantar soft tissue

The aim of this work is to provide a numerical approach for the investigation of the mechanical behaviour of the forefoot soft tissues. The development of reliable numerical models of biological structures requires the definition of constitutive formulations that actually interpret the mechanical response of the constituent biological tissues and their structural arrangement. A specific visco-hyperelastic constitutive model is provided to account for the typical features of soft plantar tissue mechanics, as geometric and material non-linearity, almost-incompressible behaviour and time-dependent phenomena. Constitutive parameters are evaluated by the analysis of experimental data from compression and stress relaxation tests on tissue samples. A three-dimensional finite element model of the forefoot region is developed starting from the analysis of biomedical images, leading to the evaluation of overall structural response. The reliability of model and analyses is assessed by the comparison of experimental and numerical results pertaining to indentation tests. The numerical model developed allows to evaluate the mechanical response of plantar soft tissue in terms of stress and strain distribution.

Treatment of diabetic foot ulcer using matriderm in comparison with a skin graft

Background

For patients with neuropathy, vasculopathy, and impairment of wound healing, treatment of a diabetic foot ulcer poses many challenges. A large number of dermal analogues have been invented in an effort to overcome these challenges. Matriderm, a dermal analogue, is made from bovine collagen and elastin. This study was conducted in order to evaluate the effectiveness of Matriderm for treatment of diabetic foot ulcers, in comparison with skin grafting.

Methods

Sixty patients with diabetic foot ulcer were included in this prospective study. The average age of the patients, who had type II diabetes mellitus, was 58 years old. The patients were allocated to an experimental or control group with their consents. The patients were selected with their consent for inclusion in an experimental group and a control group. Patients in the experimental group received a Matriderm appliance and a split-thickness skin graft, while those in the control group received only a split-thickness skin graft.

Results

A shorter hospitalization period (7.52 weeks) was observed in the experimental group than in the control group (9.22 weeks), and a shorter period of time (8.61 weeks) was required for complete healing, compared with the control group (12.94 weeks), with statistical significance (P<0.05). A higher elasticity ratio of the affected side to the non-affected side was observed in the experimental group, compared with the control group (P<0.01).

Conclusions

Matriderm enables effective healing and improves elasticity in treatment of patients with diabetic foot ulcer.

Improvement of skin quality using a new collagen scaffold in acute burns and reconstructive surgery: an in vivo evaluation of split skin graft transplantation in a rat model

INTRODUCTION

Split-thickness skin grafting is often associated with poor skin quality. In this context, a new collagen cell carrier (CCC), as an underlayment in split skin graft (SSG) transplantation for covering tissue defects in rats, has been evaluated as an improving agent.

METHODS

Twenty-eight full-thickness wounds were covered with SSGs, applying the CCC as an underlayment in 14 rats and using SSG transplantation alone in control group. Postgraft skin areas were assessed using an instrument that measures mechanical properties of skin. Three parameters were considered for skin elasticity analysis: total skin deviation (R0), gross elasticity (R2) and viscoelasticity (R8). Measurements were performed every 10 days for 80 days after grafting. Biopsies were taken subsequently for histologic evaluation.

RESULTS

The results demonstrated significantly superior elasticity values in CCC-supplemented SSGs in terms of gross elasticity and viscoelasticity (R2/R8) starting from day 60 after grafting to the end of the measuring period. There was no histologic evidence of inflammation, adverse host tissue reaction, or scar tissue formation.

CONCLUSION

Split skin grafting is associated with poor dermal quality, but CCC may offer unique opportunities in complex wound management in terms of skin graft quality improvement.

Use of sonographic elastography of the masseter muscles for optimizing massage pressure: a preliminary study

To examine the stiffness of the masseter muscle using sonographic elastography and to investigate its relationship with the most comfortable massage pressure in the healthy volunteers. In 16 healthy volunteers (10 men and 6 women), the Masseter Stiffness Index (MSI) was measured using EUB-7000 real-time tissue elastography. They underwent massages at three kinds of pressures using the Oral Rehabilitation Robot (WAO-1). A subjective evaluation regarding the comfort of each massage was recorded on the visual analogue scale. Elastography was also performed in two patients with temporomandibular joint dysfunction with the myofascial pain. The mean MSI of the right and left muscles in the healthy volunteers were 0.85 +/- 0.44 and 0.74 +/- 0.35 respectively. There was no significant difference between the right and left MSI in the healthy volunteers. The MSI was related to massage pressure at which the healthy men felt most comfortable. The two temporomandibular disorder patients had a large laterality in the MSI. The MSI was related to the most comfortable massage pressure in the healthy men. The MSI can be one index for determining the massage pressure.