Pressure garments for use in the treatment of hypertrophic scars—a review of the problems associated with their use

The molecular mechanism of hypertrophic scar

Hypertrophic scar (HTS) is a dermal form of fibroproliferative disorder which often develops after thermal or traumatic injury to the deep regions of the skin and is characterized by excessive deposition and alterations in morphology of collagen and other extracellular matrix (ECM) proteins. HTS are cosmetically disfiguring and can cause functional problems that often recur despite surgical attempts to remove or improve the scars. In this review, the roles of various fibrotic and anti-fibrotic molecules are discussed in order to improve our understanding of the molecular mechanism of the pathogenesis of HTS. These molecules include growth factors, cytokines, ECM molecules, and proteolytic enzymes. By exploring the mechanisms of this form of dermal fibrosis, we seek to provide some insight into this form of dermal fibrosis that may allow clinicians to improve treatment and prevention in the future.

Article Commentary: OB-GYN Surgeries: Why We Should Recommend to Our Patients a Preventive Management for Keloids and Hypertrophic Scars

As with all surgical specialties, gynecologists and obstetricians routinely employ surgical interventions, depending on the exact nature of the problem that they are treating. Surgery is the mainstay of gynecological therapies, and in obstetrics, surgery is frequent.

Late outcomes after grafting of the severely burned face: a quality improvement initiative

Many approaches to surgical management of the severely burned face are described, but there are few objective outcome studies. The purpose of this study was to perform a detailed evaluation of the late outcomes in adult patients who have undergone grafting using a standardized surgical and rehabilitation approach for full-thickness (FT) facial burns to identify areas for improvement in the treatment strategy of authors. This was a prospective observational study in which patients who had undergone grafting for FT facial burns by the senior investigator at a regional burn centre between 1999 and 2010 were examined by a single evaluator. The surgical approach included tangential excision based on the facial aesthetic units, temporary cover with allograft then autografting with scalp skin preferentially, split grafts for the upper eyelid, and FT grafts for the lower eyelid. Rehabilitation included compression (uvex and or soft cloth), scar massage, and silicone gel sheeting. Of 35 patients with facial grafts, 14 subjects (age 43 ± 16 years with 22 ± 21% TBSA burns) returned for late follow-up at 40 ± 33 months (range, 5-91 months). A mean of four facial aesthetic units per patient were grafted (range, 1-9 units), with six full facial grafts performed. Scalp was used as donor in 10 of 14 cases. Scalp donor sites were well tolerated with minor alopecia visible in only one case although the donor site visibly extended slightly past the hairline in two cases. Color match with native skin was rated at 8.8 ± 0.8 of 10 when scalp skin was used compared with 7.5 ± 1.6 with other donor sites (P = .06). On the lip and chin, hypertrophic scars were significantly worse compared with the rest of the facial grafts (Vancouver scar scale 8 ± 2 vs 3 ± 1, P < .01). Sensory recovery was poor with overall moving two-point discrimination at 11 ± 3 mm (range, 4-15 mm), and monofilament light touch was 3.8 ± 0.6. Graft borders were significantly more elevated than graft seams. On the forehead, the most notable problem was a gap between the graft and hairlines of the frontal scalp and eyebrows (range, 0-40 mm). Grafted eyelids required one or more subsequent ectropion releases in the majority of cases. The most common problem for the nose was asymmetry of the nostril apertures. The most problematic late outcomes that the authors identified after facial grafting for FT facial burns included relatively poor sensory return, elevation of graft edges, eyelid ectropion, gaps between grafts and hairline, and marked hypertrophic scarring around the mouth and chin. The results indicate that possible areas for quality improvement include greater attention to the limits of scalp harvest, more attention to pressure application to graft borders and the lip and chin during rehabilitation, greater accuracy in excision and graft placement on the forehead to avoid gaps with the hairlines, and counseling of the patient regarding the high probability of diminished facial sensation.

Alternate splint for flexion contracture in children with burns

Splinting children and ensuring that children wear the splint can be challenging tasks for both the therapist and the caregiver. Sometimes creativity is needed to create a pediatric splint that is easy to don and stays in place. These authors describe their challenge with pediatric burn patients either not wearing or losing their splint and how they now combine the splint directly into the pressure garment to ensure better patient compliance

Customised Pressure Garment Development by Using 3D Scanned Body Image

The objective of this research is to develop a method for designing customised pressure garments that can be more accurately applied to a burn wound area. The method includes the use of a 3D digital image of the wounded body part obtained by a body scanner and the development of a 3D pressure garment model and a 2D pattern. The scanned data contain detailed information that cannot be feasibly obtained by manual measurements, such as body curvature. The model parameters include the pressure to be exerted, pressure garment fabric properties and radius of curvature of the cross-sections of scanned body parts. By using a 3D pressure garment model, a 2D garment pattern is developed, and then, a pressure garment is constructed by using the pattern. The technique has been experimentally verified and customised pressure garments are made for a number of volunteer subjects. The customised pressure garments made for the subjects exert pressures close to the design pressure, but vary along the circumference of a given cross-section. The customised pressure garments constructed by using the developed method have shown a more accurate fit to uniformly exert the design pressure onto the whole of the wounded area.

Long-term stent use can prevent postoperative canal stenosis in patients with congenital aural atresia

OBJECTIVE

Postoperative external auditory canal (EAC) stenosis is the most common complication after congenital aural atresia (CAA) surgery. The authors applied an ear mold or hearing aid as an EAC stent following surgery and analyzed the impact on postoperative EAC stenosis.

STUDY DESIGN

Historical cohort study.

SETTING

A tertiary hospital.

SUBJECTS AND METHODS

Ninety-six patients who underwent canaloplasty between 1996 and 2010 were included in this study. To discover factors contributing to postoperative EAC stenosis, clinical parameters, including age, sex, Marx grading, Schuknecht classification, Jahrsdoerfer score, surgical approach, triamcinolone injection, and use of stenting with an ear mold or hearing aid, were reviewed and analyzed. Each stent was used for at least 6 months postoperatively. Pure-tone audiometry was performed preoperatively and 3, 6, and 12 months after canaloplasty.

RESULTS

Postoperative EAC stenosis was the most common postoperative complication, occurring in 8 (8.2%) cases with a mean time interval of 4.1 months. For patients who did not use an ear mold or a hearing aid during the postoperative follow-up period, the relative risk for the development of postoperative EAC stenosis was 5.125 (95% confidence interval, 1.428-18.400; P = .023). Other factors did not show an association with postoperative stenosis. Preoperative air-bone gap (ABG) was 49.00 dB, and closure of the ABG within 30 dB was obtained in 56.9%, 58.1%, and 48.7% of patients at the 3-, 6-, and 12-month follow-up, respectively.

CONCLUSION

Stenting with an ear mold or hearing aid might be a useful method for preventing postoperative EAC stenosis in CAA patients.

Post-burn scars and scar contractures

The mortality and morbidity from burns have diminished tremendously over the last six to seven decades. However, these do not truly reflect whether the victim could go back to society as a useful person or not and lead a normal life because of the inevitable post-burn scars, contractures and other deformities which collectively have aesthetic and functional considerations. This article gives an overview of the post-burn scars and scar contractures, especially their prevention, minimisation and principles of management.

Select practices in management and rehabilitation of burns: a survey report

The purpose of this study is to document the organization and current practices in physical rehabilitation across burn centers. An online survey developed for the specific purposes of this study sought information regarding a) logistics of the burn center; b) inpatient and outpatient treatment of patients with burn injury; and c) specific protocols in the treatment of a few complications secondary to burn injuries. Of the 159 responses received, 115 were received from the United States, 20 from Australia, 16 from Canada, and 7 from New Zealand. The overall sample included responses from 76 physical therapists (PTs) and 78 occupational therapists. Seventy-three of those surveyed considered themselves primarily a burn therapist. Nurses (86%) were reported as primarily responsible for wound care of inpatients, followed by wound care technicians (24%). Ninety-seven percent of the therapists reported following their own treatment plans. The trunk and areas of head and neck were treated by both PTs and occupational therapists, whereas the lower extremities continue to be treated predominantly by PTs. Some common practices regarding treatment of a few complications secondary to burn injuries such as splinting to prevent contractures, treatment of exposed or ruptured extensor tendons, exposed Achilles tendons, heterotopic ossification, postoperative ambulation, conditioning, scar massage, and use of compression garments are described. Opportunities exist for 1) developing a common document for practice guidelines in physical rehabilitation of burns; and 2) conducting collaborative studies to evaluate treatment interventions and outcomes.

Pressure prediction model for compression garment design

Based on the application of Laplace's law to compression garments, an equation for predicting garment pressure, incorporating the body circumference, the cross-sectional area of fabric, applied strain (as a function of reduction factor), and its corresponding Young's modulus, is developed. Design procedures are presented to predict garment pressure using the aforementioned parameters for clinical applications. Compression garments have been widely used in treating burning scars. Fabricating a compression garment with a required pressure is important in the healing process. A systematic and scientific design method can enable the occupational therapist and compression garments' manufacturer to custom-make a compression garment with a specific pressure. The objectives of this study are 1) to develop a pressure prediction model incorporating different design factors to estimate the pressure exerted by the compression garments before fabrication; and 2) to propose more design procedures in clinical applications. Three kinds of fabrics cut at different bias angles were tested under uniaxial tension, as were samples made in a double-layered structure. Sets of nonlinear force-extension data were obtained for calculating the predicted pressure. Using the value at 0° bias angle as reference, the Young's modulus can vary by as much as 29% for fabric type P11117, 43% for fabric type PN2170, and even 360% for fabric type AP85120 at a reduction factor of 20%. When comparing the predicted pressure calculated from the single-layered and double-layered fabrics, the double-layered construction provides a larger range of target pressure at a particular strain. The anisotropic and nonlinear behaviors of the fabrics have thus been determined. Compression garments can be methodically designed by the proposed analytical pressure prediction model.

Hypertrophic scarring and keloids: pathomechanisms and current and emerging treatment strategies

Excessive scars form as a result of aberrations of physiologic wound healing and may arise following any insult to the deep dermis. By causing pain, pruritus and contractures, excessive scarring significantly affects the patient's quality of life, both physically and psychologically. Multiple studies on hypertrophic scar and keloid formation have been conducted for decades and have led to a plethora of therapeutic strategies to prevent or attenuate excessive scar formation. However, most therapeutic approaches remain clinically unsatisfactory, most likely owing to poor understanding of the complex mechanisms underlying the processes of scarring and wound contraction. In this review we summarize the current understanding of the pathophysiology underlying keloid and hypertrophic scar formation and discuss established treatments and novel therapeutic strategies.

Scar and contracture: biological principles

Dysregulated wound healing and pathologic fibrosis cause abnormal scarring, leading to poor functional and aesthetic results in hand burns. Understanding the underlying biologic mechanisms involved allows the hand surgeon to better address these issues, and suggests new avenues of research to improve patient outcomes. In this article, the authors review the biology of scar and contracture by focusing on potential causes of abnormal wound healing, including depth of injury, cytokines, cells, the immune system, and extracellular matrix, and explore therapeutic measures designed to target the various biologic causes of poor scar.

Pruritus in burns: review article

Pruritus represents a common and distressing feature of burn wounds. Over the last decades, significant advances in neuroanatomical and neurophysiological knowledge have resulted in the elucidation of the mediators and pathways involved in the transmission of pruritic impulses. A plethora of therapeutic approaches have been evaluated mostly in small-scale studies involving burns patients targeting both the peripheral and the central components of the neurologic pathway. Antihistamines, doxepin, massage therapy, and transcutaneous electrical nerve stimulation are effective strategies to combat pruritus in burns patients. Recent studies have provided preliminary evidence regarding the effectiveness of gabapentin and ondansetron. The area of burns pruritus is under-researched and large-scale studies are required to reinforce the armamentarium of specialists with evidence-based regimens for the treatment of this highly distressing symptom.

The causal analysis of requested alterations for pressure garments

The purpose of this study was to examine altered pressure garments requested by burn patients, in Taiwan. Three hundred forty-two pressure garments needing alterations were collected from 127 burn patients at the Sunshine Foundation Organization, an nonprofit organization for burn patients, between March and September 2007, to identify the major defects found in these pressure garments and their causes. Causes of required alterations were classified according to a hierarchical coding scheme focusing on poor fit, discomfort, component part, fabric and sewing, and cosmetics to identify systematic problems for each garment type. The result of our analysis indicated that the majority of the pressure garment alterations were related to poor fit in circumferential and longitudinal dimensions of the various body parts, incorrect position and size of openings for eyes, nose, ears, and mouth, or inappropriate length or position of zippers. Information derived from this causal analysis can be applied in helping to reduce the recurrence of alterations in pressure garment, thus improving the quality and effectiveness of pressure therapy.

Comfort evaluation of maternity support garments in a wear trial

This study aims to evaluate the wear comfort of eight commercially available maternity support garments. The thermophysiological, sensory/tactile and movement comfort were assessed in a wear trial using a 19-item questionnaire. Fourteen pregnant Chinese women aged 32.3 +/- 4.2 years were recruited from a local obstetric clinic. The results show that the tested garments generally provided greater sensory comfort than thermophysiological comfort. The thermophysiological comfort was mainly influenced by the fibre contents and breathability. Significant linear relationships were found between material appearance and hand feel (r = 0.86, p < 0.001), and between non-itchiness and no red mark (r = 0.78, p < 0.001). Movement comfort was influenced by the garment type and style features. Overall, the soft, good-fit, cotton/elastane maternity brief was perceived as the best product. The findings of comfort needs in pregnant women and the effects of various garment attributes would be helpful for the development of maternity support garment design criteria that are required to satisfy critical ergonomic needs. Low back pain during pregnancy is a common and significant health problem. A maternity support garment is regarded as a convenient and safe device to stabilise the lumbar spine so as to relieve pain. However, patient compliance is likely to be affected by discomfort and inconvenience. The results of this study provide guidance for the optimal design of maternity support clothing.

Postburn Scars: An Update

Burn wounds give rise to the largest scars we can find in human pathology, influencing patients' quality of life. Despite the improved knowledge on pathophysiology, efficacy of the various treatments remains unsatisfactory. In this short review recent literature is examined with a focus on recent data on postburn pathological scars epidemiology and risk factors, which underline the high prevalence and the long evolution, pointing to identify this illness as a systemic inflammatory one, more frequent in women and in those of younger age, regulated by local factors relevant in wound healing.

Effects of compressive vests on pulmonary function of infants with thoracic burn scars

OBJECTIVE

To prospectively evaluate the effects of compressive vests on the pulmonary function of infants with thoracic burn scars.

METHODS

Between April 2000 and October 2005, all infants aged 2 years or less and all those aged between 2 and 3 years if they had concomitant pulmonary pathology, who were in need of a compressive vest for the treatment of burn scars to the thorax, underwent comparative pulmonary function testing under sedation with the vest closed and then opened.

RESULTS

Of the 23 infants who met the inclusion criteria, 19 had complete data. There were significant differences in oxygen saturation, respiratory rate, tidal volume/kg body weight, respiratory compliance and peak tidal expiratory flow /tidal volume, with or without vest compression.

CONCLUSIONS

Compressive vests used at our centre to treat thoracic burn scars of infants aged 2 years or less, and those aged between 2 and 3 years with concomitant pulmonary pathology, did have a statistically significant effect on their pulmonary function, but this did not translate into clinically significant differences. However, the differences observed might become clinically significant in the presence of pulmonary comorbidity or severe burns. Routine pulmonary function testing before the use of vest compression might thus benefit these infants.

Nonsurgical management of hypertrophic scars: evidence-based therapies, standard practices, and emerging methods

Hypertrophic scars, resulting from alterations in the normal processes of cutaneous wound healing, are characterized by proliferation of dermal tissue with excessive deposition of fibroblast-derived extracellular matrix proteins, especially collagen, over long periods, and by persistent inflammation and fibrosis. Hypertrophic scars are among the most common and frustrating problems after injury. As current aesthetic surgical techniques become more standardized and results more predictable, a fine scar may be the demarcating line between acceptable and unacceptable aesthetic results. However, hypertrophic scars remain notoriously difficult to eradicate because of the high recurrence rates and the incidence of side effects associated with available treatment methods. This review explores the various treatment methods for hypertrophic scarring described in the literature including evidence-based therapies, standard practices, and emerging methods, attempting to distinguish those with clearly proven efficiency from anecdotal reports about therapies of doubtful benefits while trying to differentiate between prophylactic measures and actual treatment methods. Unfortunately, the distinction between hypertrophic scar treatments and keloid treatments is not obvious in most reports, making it difficult to assess the efficacy of hypertrophic scar treatment.

Designing pressure garments capable of exerting specific pressures on limbs

Pressure garments have been used prophylactically and to treat hypertrophic scars, resulting from serious burns, since the early 1970s. They are custom-made from elastic fabrics by commercial producers and hospital staff. However, no clear scientifically established method has ever been published for their design and manufacture. Previous work [2] identified the most commonly used fabrics and construction methods for the production of pressure garments by hospital staff in UK burn units. These methods were evaluated by measuring pressures delivered to both cylinder models and to human limbs using I-scan pressure sensors. A new calibration method was developed for the I-scan system to enable measurement of low interface pressures to an accuracy of +/-2.5 mmHg. The effects of cylinder/limb circumference and pressure garment design on the pressures exerted were established. These measurements confirm the limitations of current pressure garment construction methods used in UK hospitals. A new method for designing pressure garments that will exert specific known pressures is proposed and evaluated for human thighs. Evaluation of the proposed design method is ongoing for other body parts.