Article

Identification of viscoelastic parameters of skin with a scar in vivo, influence of soft tissue technique on changes of skin parameters

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Abstract

The goal of the experiment was to develop an identification method capable of objective detection of changes of viscoelastic properties of skin with a scar remaining after a modified radical mastectomy. We compared the intact skin and the skin with a scar, a scar before and after physiotherapy. We used two methods. The first one is based on measurements of the local dynamic deformation response of the skin and the second one is the matrix identification of static deformation that identifies properties of the whole tested region of the explored tissues. We identified the skin stretchability, shiftability against deeper layers and deeply analysed both the methods. In some patients, we found statistically proven difference. In all these cases the measurement methods have detected changes of the observed tissue condition. We found both methods to be potentially applicable after further improvements as a diagnostic tool, which can contribute to the improvement of postoperative care of patients.

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... In addition, there is a change in the extension of the strain strain along the line of the scar compared to the situation in the healthy tissue, the increase of the deformation of the skin in the remaining part and the formation of the significantly greater deformation force required to cause this deformation. This puts greater demands on the muscles involved and leads to overloading, pain, and long-term effects, as well as to the conversion of an optimal movement strategy that can contribute to undesirable structural changes in skeletal, muscle and lymphatic tissue [2]. ...
... Scar issue is often neglected in these studies, even though the need for scar care is widespread [13]. It is the scar that often causes pain, reduces ROM in the shoulder cluster, changes the kinematics of the spine and posture, the patient is mentally burdened and can promote the formation of lymphedema [2,14]. ...
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Abstract. The aim of this study is to objectively determine the effect of total mastectomy on the extent of breathing movements of the thoracic and abdominal wall in the women (n =6) who underwent this operation, comparedto the breath move-ments of healthy women. Another aim is to find out whether there has been a symmetrical disturbance of the extent of movement between the operated and unoperated side of the chest and abdomen during breathing. The 3D optoelectronic kinematic analyzer (Qualisys ) has been used to measure the range of breathing movements. The chest mobility was measured in a calm and deep breathing. Further data on the patient's condition were obtained through a kinesiological analysis focused on the upperhalf of the body.The mastectomy affects the extent of breathing movements in women who have undergone this operation, by generally reducing the range of breathing move-ments on the operative side of the fuselage. For this reason, the symmetry of the rangeof movements(ROM)between the operated and unoperated sides during breathing is also impaired. The most striking asymmetries are present approxi-mately on the level of 5thribs, where the postoperative scar is also the most common. These findings have been confirmed in both quiet and deep breathing, demonstrating our claim to the need for scar care. Keywords: respiratory movements, total mastectomy, breast cancer, scar, Qual-isys
... In addition, there is a change in the extension of the strain strain along the line of the scar compared to the situation in the healthy tissue, the increase of the deformation of the skin in the remaining part and the formation of the significantly greater deformation force required to cause this deformation. This puts greater demands on the muscles involved and leads to overloading, pain, and long-term effects, as well as to the conversion of an optimal movement strategy that can contribute to undesirable structural changes in skeletal, muscle and lymphatic tissue [2]. ...
... Scar issue is often neglected in these studies, even though the need for scar care is widespread [13]. It is the scar that often causes pain, reduces ROM in the shoulder cluster, changes the kinematics of the spine and posture, the patient is mentally burdened and can promote the formation of lymphedema [2,14]. ...
Chapter
Full-text available
The aim of this study is to objectively determine the effect of total mastectomy on the extent of breathing movements of the thoracic and abdominal wall in the women (n = 6) who underwent this operation, compared to the breath movements of healthy women. Another aim is to find out whether there has been a symmetrical disturbance of the extent of movement between the operated and unoperated side of the chest and abdomen during breathing.
... The elastic component of skin's response means that energy stored allows skin to recover elastically if the force is removed and assuming the skin is not extended past the elastic limit 41 . Human skin has a complex visco-elastic property which can be described in three stages 42,43 . (i) Stage one -the collagen fibres are in a relaxed state and are bundled together; as a force is applied, the fibres gradually start to align. ...
Article
There is an interest within forensic science to understand the physical and mechanical properties of human skin and the natural and synthetic simulants used to represent it, particularly with reference to reconstruction studies that consider injury to humans, for example during sharp-weapon and ballistic impact assaults. This paper discusses literature in the broad area of (i) human skin, (ii) animal skin and products such as leather and (iii) synthetic polymeric skin simulants. The physical and mechanical properties of human skin appear to be reasonably well documented in the literature. Animal models discussed appear to be restricted primarily to pig and to a lesser extent goat, plus some data on different types of leather. All skin (human and animal) and derivatives such as leather (from various animal sources) are natural materials and therefore variable in their physical and mechanical properties. The variability of commonly used simulants for human skin such as various types of leather could impact on the confidence of any reconstruction study data obtained by using such simulants. While it is recognized that synthetic simulants (polymers such as silicone and polyurethane) do not have the structure of human skin, their physical and mechanical properties can be manipulated relatively easily to match those of skin and are typically of low variability, providing confidence in the repeatability and reproducibility of reconstruction studies.
Article
Einleitung: Patienten mit sakralen Narben, z. B. nach Sinus pilonidalis Operation, klagen teilweise über Beschwerden beim Sitzen oder bei Belastung. Um diese Beschwerden und die Narbenqualität nach unterschiedlichen Eingriffen zu objektivieren, ist es von Interesse die Hautqualität in der Sakralregion zu beurteilen. Wir entwickelten ein mechanisches, noninvasives, schnelles und kostenneutrales Messverfahren in welchem Hautdehnbarkeit und -verschieblichkeit abgebildet werden. 100 gesunde Probanden wurden mit diesem Verfahren untersucht, um Normwerte der unvernarbten Sakralhaut einzuschätzen und Einflussfaktoren auf die Hautqualität wie Alter, Gewicht und Geschlecht zu identifizieren. Methodik: 4 vertikal angeordnete Messpunkte mit dem exakten Abstand von 10 mm–100 mm–10 mm werden bei dem aufrecht stehenden Probanden kaudal auf den Rücken aufgetragen. Der Proband lehnt sich nun nach vorne und berührt mit ausgestreckten Armen und Beinen beidseits die Patella mit dem Handballen. Der Abstand der Punkte wird in dieser Position erneut gemessen. Im aufrechten Stand wird daraufhin ebenfalls der Abstand gemessen, um den der unterste Punkt manuell nach kranial geschoben werden kann. Ergebnisse: Der aus den Messwerten einfach zu berechnende sakral-lumbale Hautdehnungsquotient (lumbale Hautdehnung / sakrale Hautdehnung×100) ist alters- und BMI-unabhängig und hat einen Normbereich von ca. 80–93%. Die sakrale Hautverschieblichkeit liegt zwischen 11 und 18 mm, wird jedoch von einem hohen BMI leicht negativ beeinflusst. Schlussfolgerung: Mithilfe unserer Messmethode können Operationsverfahren im Sakralbereich bezüglich der resultierenden Hautelastizität miteinander verglichen werden. Durch Vergleich der lumbalen mit der sakralen Hautdehnung desselben Probanden gewinnen wir eine intraindividuell gültige Aussage über mögliche Veränderungen. Da uns bislang keine veröffentlichten Daten über die sakrale Hautelastizität bekannt sind, scheint das Messverfahren praktikabel und relativ unabhängig von der Konstitution des Patienten zu sein. Im Vergleich zu bislang zur Elastizitätsmessung an anderen Hautarealen eingesetzten technischen Geräten ist unser Verfahren überall verfügbar und kostenneutral.
Introduction: Clitoral phimosis is adherence of the clitoral prepuce to the glans and can result from inflammatory dermatoses, blunt trauma, chronic infection, and inadequate hygiene. Aim: The aim of this report was to demonstrate myofascial release (MFR) techniques utilized by a physical therapist to treat clitoral phimosis. Methods: The patient was a 41-year-old woman with low back pain, a bruised sensation of her pubic region, vulvar pain provoked by sexual arousal, decreased clitoral sensitivity, dyspareunia, and anorgasmia. The patient sustained a blunt trauma injury to the vulva. Examination revealed lumbosacral and pelvic dysfunction, pelvic floor muscle dysfunction, bone bruise of the pubic bone, and decreased retractability of the clitoral prepuce and scarring. Eleven physical therapy sessions over 16 weeks included stretching, joint mobilization, muscle energy techniques, transvaginal pelvic floor muscle massage, clitoral prepuce MFR techniques, biofeedback, Integrative Manual Therapy (IMT) techniques, nerve mobilization, and therapeutic and motor control exercises. The patient applied topical clobetasol 0.05% cream for 30 days. Results: The low back pain was reduced and full resolution of her vulvar pain, dyspareunia, and pubic bone bruised sensation resulted. Mobility of the clitoral prepuce was restored. Normal clitoral sensitivity and clitoral orgasm returned. Symptom resolution was confirmed upon telephone evaluation at 6 months. Conclusion: With proper training, physical therapists managing patients with dyspareunia can identify clitoral phimosis and use specific MFR as a conservative treatment approach. Physical therapy techniques can be performed alone or in concert with medical therapy.
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Sexual life after cancer depends on the type of cancer, the treatments used and the importance given to sexuality by the patient and his or her partner. Some types of cancers which can cause particular problems include facial or genital cancers, colon cancers, or prostate, rectum or bladder cancer. Furthermore, some treatments, particularly chemotherapy, create physical discomfort :and fatigue which can hinder resumption of sexual life. Preconceptions associated with cancer also make sexual life difficult. In the case of breast cancer, such preconceptions are aggravated by the additional erotic function of the breast in society. The psychological therapies following mastectomy, such as psychopharmacology, psychotherapy of depression, plastic surgery for psychological purposes, can be accompanied by therapy for the couple and sexual education.
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Active scars are a model of soft tissue lesions. Soft tissues surround everywhere the locomotor systém. They have to shift and stretch in harmony with joints and muscles. Active scars interfere with this type of movement thus disturbing the function of the entire motor system. Clinical diagnosis is based on increased resistance of the surface to stretch, by a thickened fold of deep connective tissue, by impaired mobility against deep tissues in particular bone and resistance palpated in the abdominal cavity, which gives under slight pressure. 51 cases are presented which have benn sufficiently followed up, mainly scars after surgery. The patients suffered from various types of what is called myofascial pain. Treatment consisted mainly of soft tissue manipulation making use of the barrier phenomenon. As lesions of function are multifactorial as a rule, active scares, too, are frequently only one of many factors. Therefore its relevance is dicisive. They proved to be highly relevant in 36 cases, only partly relevant in 13 and entirely irrelevant in 3 cases. Treatment of active scars is highly effective in a great number of patients, in particular after surgery. If undiagosed and untreated they are an important cause of therapeutic falure and recurrence. It also widens the scope of manipulative therapy.
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The dynamics of the deformation response of the body surface depends on mechanical properties of the skin and subcutaneous structures. The determination of visco-elastic parameters of the skin may be a prospective tool of diagnostics in dermatology as well as a potential source of information in the biological age assessment in gerontology. From the practical point of view, the analysis of a deformation response of the skin (and its changes) can be useful for the assessment and control of effects of cosmetics. The analysis of the dynamics of a deformation response of the skin, the structure of a rheological model and its typical parameters are presented in the paper. The transient deformation response consists of two distinct exponential components. The time constant of a "rapid" exponential curve is typically of order 10 ms, while the time constant of a "slow" exponential curve is of order 0.1 to 1s. The corresponding model involves a serial-parallel combination of two Hook's and two Newton's bodies. The time constant of the slow exponential curve increases significantly with age. The increase is mainly connected with the decrease of the value of the parameter of a corresponding Hook's body. The demonstration of the application of the suggested methodology is further presented in the paper. An "antiaging" cosmetic cream containing antioxidants and liposomes was used for the demonstration. The time constant of the slow exponential curve decreases significantly after its application. Nevertheless, the decrease was connected with the decrease of the parameter of a corresponding Newton's body. Consequently, the effect of the cream does not lie in reversing the aging of skin.
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The non-linear viscoelastic properties of skin tissue were characterized by modulus of elasticity E, which represents stiffness, and percentage extension (strain, xi) at load intensities of 20, 40 and 100 gm. The latter property is a measure of the extensibility for both normal skin and hypertrophic scar. A quasi-static extensometer applies a standard rate of extension to the skin and its mechanical properties were obtained from 15 Chinese patients with burn injuries of superficial to full skin thickness burns. Clinical evaluation of hypertrophic scar is qualitative and depends on colour, thickness and hardness or firmness. Using mechanical properties assists in the characterization by providing a quantitative indicator. Higher scar grading is synonymous with increased stiffness and decreased extensibility. Correlation with clinical assessment was achieved with these in vivo viscoelastic properties.
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In human dermis, collagen bundle architecture appears randomly organized, whereas in pathological conditions, such as scar tissue and connective tissue disorders, collagen bundle architecture is arranged in a more parallel fashion. Histological examination by one or two observers using polarized light is the most common method to determine collagen orientation. The hypothesis on which this study is based is that an objective image analysis technique, Fourier analysis, would improve the reliability (are the measurements reproducible?) and the accuracy (does the method measure what it is supposed to measure?) of collagen orientation assessment, compared with observer ratings. Fourier analysis was applied to 271 images of scar tissue and normal skin that were acquired by confocal laser-scanning microscopy. Observers rated the same areas using polarized light as well as the confocal microscopy images. Computer images consisting of different types of ellipses were generated with a fixed orientation. Observers and Fourier analysis evaluated the images to evaluate accuracy. The inter-observer reliability was acceptable when at least three observers rated polarized light images (r > 0.69), whereas two observers were sufficient for rating confocal microscopy images (r > 0.71). Fourier analysis correlated better with observer ratings of confocal microscopy images (r = 0.69) than with polarized light microscopy images (r = 0.42). Fourier analysis was more accurate than four observers for the evaluation of the 'true' orientation for almost all types of computer-generated images. For the first time it is shown that Fourier image analysis is suitable for the morphometry of dermal collagen orientation and leads to a superior measurement of collagen orientation compared with subjective histological evaluation by several experts. If an evaluation is performed by conventional light microscopy, at least three observers are required to attain an acceptable inter-observer reliability.
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When a wound heals, as everyone has observed, it contracts, thickens and wrinkles the neighbouring skin, forming a scar. The morphology of the scar depends on the type of wound; an urgent tracheotomy leads to a very different scar than a carefully planned face lift. The surgical challenges of intrusive procedures such as removal of skin lesions, skin transplantation or grafting, and scar removal are complicated by the complex geometry and stress states in different parts of the body. We show that, for relatively general conditions, the nature of the localisation of the scar is determined by the background tension of the skin which can arrest the formation of wrinkles around a scar. Our physical experiments to simulate this procedure indicate that the region deformed by the defect has a characteristic length scale r* approximately 1 square root of tau, where tau is the natural tension of the skin.
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