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PubMed1991

Circulatory and metabolic changes in expanded pig skin flaps.

To evaluate circulatory and metabolic changes in pig skin during tissue expansion, the buttock skin of 12 pigs was expanded for 5 weeks. In a second operation, island buttock flaps were elevated bilaterally. Flap temperature, laser Doppler flow (LDF), and fluorescein penetration borders were recorded. Norepinephrine infusions were given twice. After cannulation of the external iliac veins, the total venous outflow from the flaps and metabolic parameters such as glucose and oxygen consumption and lactate production were measured bilaterally. No significant difference in fluorescein staining was found, but laser Doppler flow in the expanded tissue was higher than in nonexpanded skin, whereas the total flap blood flow was not significantly different. A flow reduction was seen in expanded flaps during norepinephrine infusion, whereas nonexpanded flaps showed a slightly increased blood flow. This adrenergic supersensitivity indicates that it is possible that not only surgical nerve section but also tissue expansion can result in sympathetic denervation. No differences in the metabolic parameters were observed.

Animals↗
PubMed1994

Venous ischemia in skin flaps: microcirculatory intravascular thrombosis.

Although endothelial cell injury and microcirculatory intravascular clotting have been implicated in the pathophysiology of skin-flap failure and various hematologically active drugs have been used to improve flap survival, the basic underlying pathophysiology has not been documented previously. In this study of venous ischemia in pig flaps, we focus on the accumulation and distribution of platelets and fibrinogen in the flap, on the morphologic changes in the flap microcirculation, and on changes in various coagulation factors in the venous effluent from the flap. Bilateral buttock skin flaps and latissimus dorsi myocutaneous flaps were designed and elevated on 12 pigs. All flaps had a primary ischemic insult (clamp application to the vascular pedicle) of 2 hours, followed by 2 hours of reperfusion, and then one side was subjected to a 6-hour period of secondary venous ischemia (clamp application to the dominant flap vein). In six animals, radioactively labeled autologous platelets and human fibrinogen were injected intravenously half an hour before termination of secondary venous ischemia. Flaps were weighed and counted for radioactivity. Flap biopsies and the buffy coat of venous effluent were processed for electron microscopy. In the other six animals, venous effluent was collected before secondary ischemia, upon immediate reperfusion, and at 4 and 8 hours after termination of secondary ischemia. Venous plasma levels of fibrinogen, von Willebrand factor, and antithrombin III were measured. Platelet and fibrinogen accumulation was increased in flaps with venous stasis when compared with control flaps at both time intervals studied; a twofold increase was seen prior to reperfusion, and a threefold increase was seen following 4 hours of reperfusion. Venous effluent could not be collected from buttock skin flaps because of slow reflow and clotting in the collecting system. In comparing the venous effluent of control flaps with that of venous ischemic latissimus dorsi flaps, hematocrit was significantly elevated. Blood samples collected for analysis of fibrinogen, antithrombin III, and von Willebrand factor could not be analyzed because of postcollection clotting. Electron microscopy showed extravasation of red blood cells and activated platelets, fibrin, and red blood cells in distended and partly disrupted capillaries. The venous ischemia reperfusion injury is associated with thrombosis in the microcirculation and alterations in consumption of coagulation factors. This study gives physiologic support for potential beneficial effects of treatment modalities that aim at counteracting the different components of thrombus formation.

Animals↗
PubMed1989

A comparison of actual and apparent lumbar lordosis in black and white adult females.

The purposes of this study were to investigate differences in lumbar lordosis in black and white adult females and to explain the clinical impression that blacks have a greater lordosis than whites. An actual lumbosacral lordosis angle (ALS) was measured from a standing right lateral lumbosacral radiograph using the angle formed from the intersection of lines drawn across the top of the second lumbar vertebral body (L2) and across the top of the sacrum. An actual lumbo-lumbar angle (ALL) was measured in the same manner, except the second line was drawn across the bottom of the fifth vertebral body (L5). To determine whether gluteal prominence gives a false impression of increased lumbar lordosis, an apparent lordosis (APL) measurement was taken, measuring the distance from the subject's greater trochanter to the most posterior aspect of the buttocks. No significant differences were found in ALS or ALL between 25 black and 27 white adult female subjects (ALS, P = 0.26; ALL, P = 0.41). Significant differences were found between black and white APL, with blacks demonstrating a larger APL than whites (P less than 0.01). A high correlation was noted between ALS and ALL in both blacks (0.70, P less than 0.01) and whites (0.77, P less than 0.01). The investigators therefore contend that the clinician's assumption that blacks have a greater lordosis than whites is based on an apparent increased lordosis due to more prominent buttocks (APL).

Adolescent↗
PubMedDate not supplied

Patients with epilepsy: a high-risk population prone to severe burns as a consequence of seizures while showering.

We document the severe burns sustained by three patients with epilepsy who suffered seizures while showering. On the basis of the circumstances of these accidents, we suggest preventative measures to help other patients with epilepsy avoid similar burn injuries. Patient data collected from January 1987 to May 2004 by the Burn Unit of the Department of Plastic Surgery, University of Aachen, Germany, were reviewed. Three patients with epileptic disorders were found who suffered severe burn injuries caused by seizures that occurred while showering. Scald location and depth was assessed. Three patients (two women, one man) sustained extensive scald injuries after epileptic seizures while showering. Burn extent ranged from 20% to 35% TBSA. Scalds primarily affected the trunk, legs, arms, and buttocks. Two of the three patients used showers with levers for controlling water temperature. Safety devices for limiting water temperature were absent. All patients used shower cubicles. Patients with epilepsy may sustain serious burns, typically affecting the trunk, legs, arms, and buttocks, when a seizure occurs while showering. We suggest that individuals with epilepsy use showers designed with pirouetting taps, rather than levers, to regulate water temperature. Pirouetting taps are less likely to be shifted out of position during a seizure. We also recommend that epileptic patients have safety devices installed in their water heaters that limit maximum water temperature. Such safety devices prevent scald injury. And, finally, we suggest that people with comparable disorders generally avoid using shower cubicles. Instead, showers with curtains should be used, which may allow occupants to escape from dangerously hot shower water more easily.

Accident Prevention↗
PubMed2006

Minimum 5-year analysis of L5-S1 fusion using sacropelvic fixation (bilateral S1 and iliac screws) for spinal deformity.

STUDY DESIGN: Clinical radiographic and outcomes investigation. OBJECTIVE: To investigate clinical and radiographic outcomes for lumbosacral fusion (in patients with spinal deformity) using a combination of bilateral sacral and iliac screws with a minimum 5-year follow-up. SUMMARY OF BACKGROUND DATA: To our knowledge, long-term results (>5 years of follow-up) of bilateral S1 screw/bilateral iliac screw fixation have never been published or presented. MATERIALS AND METHODS: A total of 67 patients (from an initial consecutive cohort of 81) undergoing lumbosacral fusion with bilateral sacral and iliac screws with a minimum follow-up of 5 years (range 5-10 + 5, average 6 + 3) were analyzed for radiographic outcome and clinical course by an outcome questionnaire (administered at ultimate follow-up) analysis. Patients were divided into 2 groups: group 1, 34 patients with mostly high-grade spondylolisthesis; and group 2, 33 with adult scoliosis fused mostly from the thoracic spine to the sacrum. A true anteroposterior pelvis film was obtained in all patients to assess for sacroiliac joint arthritis, as were standard spine radiographs. Patients were administered Oswestry and directed buttock pain questionnaires at latest follow-up. RESULTS: There were no cases of sacral screw failure (i.e., screw loosening, partial screw pullout, or fracture of the sacral screw). There were 5 cases of nonunion at L5-S1. Of the 5 cases, 3 did not have anterior column support at L5-S1. Four of the 5 cases were revised, and, subsequently, 3 achieved union. Iliac screws were removed electively on 1 or both sides in 23 of the patients after 2 years postoperatively because of prominence. There were 7 cases of iliac screw breakage. Iliac screw halos were observed in 29 patients. No sacroiliac osteoarthritis was observed on the true anteroposterior pelvis films. At ultimate follow-up, average visual analog painscale (0-10) score to assess buttock pain was 2.4, and average Oswestry score was 20.1. CONCLUSIONS: For high-grade spondylolisthesis and long adult deformity fusions to the sacrum, a montage of bilateral S1 screws and iliac screws were effective in protecting the sacral screws from failure. Pseudarthrosis at L5-S1 was manifested by rod breakage at that level. We saw no evidence of a long-term effect of the iliac screws predisposing the sacroiliac joints to degeneration at follow-up ranging from 5 to 10 years.

Adolescent↗
PubMed1999

A method for custom-contoured cushion design using interface pressure measurements.

The interface pressure distributions between flat foam cushions and the buttocks of seated test subjects were compared to custom-contoured cushion surface shapes generated with a seated-buttock contour gauge. Our hypothesis was that pressure measurements could be used to generate a contour equivalent to that obtained with a force-deflection contour gauge. The study was performed in a university medical center using spinal cord injured (SCI) (12) and elderly (30) test subjects. Interface pressure was measured using a pressure mapping pad. Contour shape was measured using an electronic force-deflection contour gauge. Pressure and contour information were reduced prior to analysis using singular value decomposition. Polynomial regressions were performed on the values in the first singular vectors of the corresponding pressure and contour decompositions. Relationships best described by cubic polynomials were detected between pressure and contour shape suggesting that interface pressure predicts optimal contour shape.

Aged↗
PubMed1984

Morphologic alterations of epidermal melanocytes and melanosomes in PUVA lentigines: a comparative ultrastructural investigation of lentigines induced by PUVA and sunlight.

Ultrastructural studies were conducted in order to determine morphologic and functional differences in melanocytes and melanosomes in PUVA lentigines and solar lentigines, and light-protected buttock skin. Compared to melanocytes in solar lentigines from 7 subjects and light-protected buttock skin from 5 subjects (none of these subjects had received UV radiation therapy), melanocytes in PUVA lentigines from 6 subjects generally had longer and more numerous dendrites, and showed more active melanogenesis. Basal keratinocytes in PUVA lentigines had a significantly increased frequency of large, single melanosomes, and revealed significantly larger individual melanosomes within compound melanosomes. Other findings in some PUVA lentigines included the close apposition of Langerhans cells to melanocytes, and atypical nuclear, cytoplasmic and melanosomal alterations, including melanosomal pleomorphism and melanin macroglobules. The presence of relatively large and predominantly single melanosomes in basal keratinocytes of PUVA lentigines suggests more active melanogenesis and/or an irreversible somatic alteration. It will be important to determine the clinical course and ultrastructural findings of PUVA lentigines that persist long after PUVA is discontinued.

Adult↗
PubMed1984

Ultrastructural abnormalities of the microvasculature and elastic fibers in the skin of juvenile diabetics.

We examined by electron microscopy the calf and buttock skin of 15 juvenile diabetics, 9-36 years old, to determine whether microangiopathy was present. We found in 14 of 15 buttock specimens, and in all 15 calf skin specimens, that the vascular walls were thickened by the peripheral deposition of a belt of basement membrane-like material admixed with variable amounts of collagen (reticulin) fibrils. In addition there appeared to be an increased amount of unidentified material, most likely basement membrane, deposited within the vascular wall itself. We also found age-related elastic fiber abnormalities in the dermis and in the arterioles which were identical to those observed in normal, nondiabetic aged individuals 50-93 years old. We suggest that the vascular and elastic fiber abnormalities in diabetic skin may represent a manifestation of accelerated aging rather than being related to the various underlying metabolic derangements in diabetes.

Adolescent↗
PubMed1985

Actinic degeneration in association with long-term use of PUVA.

To determine the extent of clinical actinic damage that occurred in association with exposure to oral methoxsalen photochemotherapy (PUVA), dermatologists at 16 university centers assessed the wrinkling, telangiectasia, and altered skin markings on the buttocks and the dorsa of the hands among 1380 patients treated with PUVA. These changes are similar to those seen in skin that is chronically exposed to sunlight. After more than 5 years of prospective study, patients with psoriasis exposed to PUVA showed a significant dose-dependent increase in the prevalence of clinical actinic degeneration of the skin of the buttocks (p less than .05, F-test). The prevalence of moderate or severe change among those patients exposed to high doses of PUVA (more than 160 treatments) was low (11%). The degree of increased clinical actinic degeneration noted on the dorsa of the hands was also significantly related to total exposure to PUVA (p less than .05, F-test). Our findings indicate that long-term PUVA exposure is associated with an increase in clinical actinic degeneration of the skin. However, the magnitude of this increase is small and, after more than 5 years, is of limited clinical consequence to most patients.

Adult↗
PubMed1995

Reduced type I and type III procollagens in photodamaged adult human skin.

We have quantitatively assessed the relation between type I and type III procollagen precursor levels and the severity of clinical photodamage in human skin. Levels of procollagen, pN collagen (collagen without the carbroxypropeptide), and/or pC collagen (collagen without the aminopropeptide) were determined by radioimmunoassay, Western blot, and immunohistology in punch biopsy specimens from mildly and severely photodamaged forearm skin and from sunprotected underarm and buttock skin of the same subjects. Collagen precursor levels in forearm and underarm skin were expressed relative to buttock levels for comparison. In the mildly photodamaged group, collagen precursors in the forearm did not differ from those in the underarm by any measurement, except for type I collagen precursors measured by radioimmunoassay, which were reduced 16%. In severely photodamaged forearm skin, both type I and type III collagen precursor levels, measured by radioimmunoassay, were significantly reduced (approximately 40%). Western analysis revealed similar significant reductions in type I and type III collagen precursor levels in severely photodamaged forearm skin compared with the sun-protected underarm. Immunohistology localized both type I and III pN collagens predominantly to the extracellular papillary dermis. Relative staining intensities of type I and type III pN collagen were also significantly reduced in severely photodamaged forearm skin. Multiple linear regression modeling of all data demonstrated that reductions in collagen precursor levels were significantly correlated (p < 0.03) with the severity of photodamage, but not with chronologic age. These data demonstrate, by three independent methods, coordinate reductions of both type I and type III collagen precursors in photodamaged human skin, and the degree of reduction correlated with the degree of photodamage. It is likely that such changes in collagen precursors lead to reduced levels and/or altered organization of fibrillar collagen, and thus may contribute to the wrinkled appearance of photodamaged human skin.

Adult↗
PubMed1991

Collagen cross-linking in sun-exposed and unexposed sites of aged human skin.

A recently described nonreducible, acid-heat stable compound, histidinohydroxylysinonorleucine (HHL), is a collagen cross-link isolated from mature skin tissue. Its abundance is related to chronologic aging of skin. The present communication describes the quantity of HHL from aged human skin of the same individuals in sun-exposed (wrist) and unexposed (buttock) sites. Punch biopsies were obtained from these sites from nine people of age 60 or older. HHL contents (moles/mole of collagen) at these sites were for wrist 0.13 +/- 0.07 and for buttock 0.69 +/- 0.17 (mean +/- SD, p less than 0.001). In addition, it was found that acute irradiation of the cross-linked peptides with UVA (up to 250 J/cm2) and UVB (up to 1 J/cm2) had no effect on HHL structure. The same treatment significantly degraded another nonreducible, stable collagen cross-link, pyridinoline. The results suggest that chronic sunlight exposure may be associated with an impediment to normal maturation of human dermal collagen resulting in tenuous amount of HHL. Thus, the process of photoaging in dermal collagen is different from that of chronologic aging in human skin.

Adult↗
PubMed1982

Role of the microcirculation in the treatment and pathogenesis of psoriasis.

Controversy exists whether the initiating events in psoriasis are primarily epidermal or dermal (vascular). To study this point, serial biopsies from 6 patients were taken from the periphery of individual plaques before, and at 1 to 3 day intervals during, Goeckerman and PUVA treatments. Part of the biopsy was studied by electron microscopy to determine the fine structure of the capillary loops and part was incubated with tritiated thymidine to determine the labeling index (LI) of the basal cells. Normal appearing buttock skin of the 11 other psoriatic patients not under treatment was studied by identical methods. In 4 of the 6 treated patients, the capillary loops began to return toward normal 3 to 8 days before the LI began to decrease. Two patients did not show a return toward normal of either capillaries or LI during the period of the experiment. The LI was elevated in the normal appearing buttock skin of 6 of 11 untreated psoriatics. In 4 of the 6, the loops were normal arterial capillaries. We did not observe abnormal (venous) capillaries associated with a normal LI in the other 5 untreated patients. These data support the concept that the initiating factors in psoriasis are in the epidermis, but epidermal hyperplasia cannot occur without vascular proliferation. Understanding the factors responsible for shortening the capillary loops during epidermal normalization and for inhibition of capillary growth in the presence of an increased LI could lead to other ways of controlling psoriasis.

Autoradiography↗
PubMed1982

Studies in cutaneous aging: I. The elastic fiber network.

We studied by light and electron microscopy the elastic fibers in he sun exposed and sun protected skin of normal and psoriatic individuals of different ages in order to separate the changes of actinic damage from those of chronological aging. The sun exposed skin showed 2 types of elastic fiber abnormalities-one related to actinic damage and the other to chronological aging. The sun protected buttock skin showed only the latter. From ages 30 to 70, a minority of the elastic fibers exhibited abnormalities that appeared to represent a process of fiber disintegration. After age 70, the majority of elastic fibers showed these abnormalities. These abnormalities were present without accompanying inflammatory cells. Also, there was morphological evidence of continuing synthesis of elastic fibers during the lifetime of these subjects, except that from ages 50-93, the fibers appeared to be loosely, rather than compactly, assembled. Incubation of dermal slices from buttock skin of young adults with porcine pancreatic elastase and bovine chymotrypsin produced elastic fiber degradation that closely simulated the changes that were observed in aged sun protected skin. We propose that one of the features of cutaneous aging is a slow, spontaneous, progressive degradative process inherent in the elastic fiber that can be enzymatically accelerated from decades to hours by elastase and chymotrypsin.

Adolescent↗
PubMed1982

Studies in cutaneous aging: II. The microvasculature.

We studied by light and electron microscopy the microcirculatory vessels in the sun exposed and sun protected skin of normal and psoriatic individuals in order to separate the features of actinic damage from those of chronological aging. In actinically damaged skin, the vascular walls of postcapillary venules and of arterial and venous capillaries were thickened by the peripheral addition of a layer of basement membrane-like material. The veil cells which were intimately related to these layers often had dilated cisternae of rough endoplasmic reticulum containing electron dense material. In 3 of 8 individuals, 70, 70 and 72 yr old, the buttock skin showed mold vascular wall thickening. In 5 other patients, 59-88 yr old the vessels of the buttock skin were normal. In 4 individuals 80-93 yr old, the vessels were abnormally thin (0.5-1.0 micrometer). The veil cells were either absent or decreased in number in these specimens. We propose that (1) the veil cell is responsible for the synthesis and maintenance of the peripheral portion of the vascular wall of the dermal microcirculatory vessels; (2) the veil cell is stimulated to produce excessive basement membrane-like material in response to UV light, factors associated with diabetes mellitus, and possibly to factors associated with the early phase of chronological aging; and (3) with progressive aging there is a decrease in the number and synthetic activity of veil cells which correlates with the appearance of abnormally thin walled vessels.

Age Factors↗
PubMed2006

The difference between the constitutive and facultative skin color does not reflect skin phototype in Asian skin.

BACKGROUND/PURPOSE: The assessment of the sensitivity of human skin to ultraviolet (UV) radiation is important in the area of phototherapy, photodermatoses, photo-aging, photo-carcinogenesis, and photo-protection. Some reports have shown that quantitatively measured skin color is a good indicator for predicting UV sensitivity to human skin in Caucasians. In this study, our aim was to define the correlation between skin color and the skin phototype assessed by the Fitzpatrick method in Asian brown skin. METHODS: A total of 180 medical students with similar life styles were included in this study. Their skin phototype was classified according to the system introduced by Fitzpatrick. Then, using a Minolta Spectrophotometer CM-2002, their skin color was determined on the buttocks and forehead. The buttock color was taken as the constitutive skin color, and the forehead color as the facultative skin color. Using these measured values, we compared the skin color with the skin phototype to find their correlation. Also, we investigated whether the difference between the constitutive and facultative skin colors of each individual had a relationship with his or her skin phototype. RESULTS: The constitutive skin color became darker with increasing skin phototype, and this change was statistically significant. As for the facultative skin color, it also became darker with increasing skin phototype, but was less well correlated with the skin phototype than the constitutive skin color. However, the difference between the constitutive and facultative skin colors did not show consistent results in predicting the skin phototype. CONCLUSION: In this study, we found that the constitutive skin color can be a good indicator of the skin phototype. However, the difference between the constitutive and facultative skin colors of each individual does not give any meaningful information for the assessment of his or her skin phototype in Asian skin.

Adult↗
PubMed2000

Squamous cell carcinoma arising in chronic perianal pyoderma a case report and review of Japanese literature.

We report a rare case of squamous cell carcinoma developing from fistules of chronic perianal pyoderma in a 49-year-old Japanese man. He first noticed an abscess and nodule on his buttocks and perianal area 21 year previously (at the age of 28); the fistules formed later. These fistules were surgically removed, and an artificial anus was constructed 14 years ago (at the age of 35) in our hospital, when a histopathological examination revealed no malignant changes. However, he was recently admitted to our hospital with arterial bleeding from the ulcer of the buttock. On admission, the histological diagnosis of the ulcer was well differentiated squamous cell carcinoma. Wide local excision of the ulcer and scar tissue, including the sacrum, was performed. The defect was covered with a left latissimus dorsi flap and skin graft. He received radiation therapy after the operation. However, he died of cachexia and pneumonia. This case indicated that the CPP would better have been treated with wide excision before the development of SCC. Therefore, we recommend careful follow-up of patients affected by CPP and repeated biopsies of the lesion, particularly when the condition is severe, longstanding, and extensive. We discussed the term "CPP" and reviewed 22 cases of SCC arising in CPP reported in the Japanese literature.

Anus Neoplasms↗
PubMed2004

Polypoid Basal cell carcinoma on the perianal region: a case report and review of the literature.

We report the case of an 88-year-old Japanese woman with polypoid BCC on the perianal region. The basaloid, solid aggregations of BCC were limited to the upper to middle part of the polypoid area. A review of the English and Japanese literature that excluded cases of fibroepithelioma of Pinkus found 21 total cases in which the polypoid BCC could be recognized as a variant of nodular BCC. The following points were used to categorize the lesions: 1) characteristic polypoid appearance that often mimics clinically benign or malignant adnexal neoplasms, melanocytic nevus, or malignant melanoma; 2) the peculiar favorable locations such as scalp (23.8% of the 21 cases), genital area (23.8% of the cases), and back-buttock areas (19% of the cases). These areas suggest that etiologic factors other than ultraviolet radiation exposure are involved in such cases. These characteristic locations may also be the main reason why fibroepithelioma of Pinkus type BCCs frequently manifest with a polypoid appearance, because these types of BCCs also have similar preferred sites such as the back-buttock and genital areas. Polypoid BCCs appear to affect more women than men than do nodular BCCs (7 men and 14 women). Although the polypoid BCCs have a large average size, they are not considered aggressive because the lesions are well-circumscribed and the growth patterns are non-infiltrative.

Aged↗
PubMed2006

A case of the hyperkeratotic variant of porokeratosis Mibelli.

Herein, we report a case of the hyperkeratotic variant of porokeratosis Mibelli. A 58-year-old woman presented with two brownish verrucous plaques on the buttock for 20 years, and extremely hyperkeratotic verrucous nodules and brownish macules on the right foot for 1 year. Histopathological findings of the buttock were typical of porokeratosis. However, histopathological findings of the right foot were atypical for porokeratosis, including extreme hyperkeratosis and an increased number of and unusual sized cornoid lamellae.

Female↗