The Value of Negative-Pressure Wound Therapy and Flap Surgery in Hidradenitis Suppurativa - A Single Center Analysis of Different Treatment Options.

Background: Hidradenitis suppurativa is manifested by painful abscesses and scarring of sweat glands. Axillary, inguinal and genital regions are mostly affected. Multiple options exist in the treatment of hidradenitis suppurativa. The aim of this retrospective, mono-center cohort study was to analyze the outcome of different treatment methods after radical excision of hidradenitis suppurativa. Methods: We retrospectively evaluated the treatment strategy and recurrence rate of hidradenitis suppurativa. We included all eligible patients of legal age between February 2003 and October 2021, with the diagnosis of Hidradenitis suppurativa and the necessity for surgical treatment. All patients with surgical treatment and direct wound closure by suture were excluded. Bacterial load and flora were analyzed for primary and secondary reconstruction in combination with negative-pressure wound therapy. Patient data were analyzed for recurrence rate and remission time according to different reconstructive techniques. Results: In 44 affected anatomical sites (n = 23 patients) we treated 15 patients with negative-pressure wound therapy. Bacterial load and flora were lower in the last wound swab of patients with multi-surgical procedures (22 localizations) compared to the first wound swab independent of the use of negative-pressure wound therapy.Wound closure, independent of a direct and multi-stage procedure was achieved by local fasciocutaneous flaps (n = 12), secondary intention healing (n = 7), secondary intention healing with buried chip skin grafts (n = 10), or split-thickness skin grafts (n = 15). Radical excision combined with split-thickness skin grafts showed the lowest recurrence rate in the follow-up (16%; n = 4). Conclusion: Radical excision of hidradenitis suppurativa as gold standard for surgical treatment combined with negative-pressure wound therapy as multi-stage procedures ultimately reduced bacterial load and flora in our study. The use of split-thickness skin grafts showed the lowest recurrence rate.

Leaving the perfusion zones? Individualized flap design in 100 free DIEP and ms-TRAM flaps for autologous breast reconstruction using indocyanine green angiography.

BACKGROUND: There is still no consensus regarding the ideal zoning in abdominal-based autologous breast reconstruction using free DIEP or ms-TRAM flaps. In particular, the perfusion pattern of the flap according to the number of perforators used and their location remains controversial. In this study, the perfusion of free DIEP and ms-TRAM flaps is assessed intraoperatively and analyzed with regard to different perfusion patterns. METHODS: A retrospective analysis of 100 free flaps for breast reconstruction was performed. Following complete flap harvest, we used indocyanine green angiography for perfusion analysis. By applying two different contour levels, DIEP flaps with lateral or medial perforators and ms-TRAM flaps were assessed for their respective perfusion patterns. RESULTS: No statistically significant differences were found in the size of the perfusion area between the different flap types when applying the contour level of 20% (p >0.05). For the contour level of 30%, however, statistically significant differences were found between DIEP flaps with medially or laterally located perforators (p = 0.038). Laterally or medially located perforators in DIEP flaps showed no significant differences in their ability to cross the midline (contour level 20%, p = 0.068; contour level 30%, p = 0.058). CONCLUSION: Considering the variability of the perfusion of the abdominal wall and the high sensitivity of indocyanine green angiography for their detection, the abdominal zonings play a minor role. By using intraoperative indocyanine green angiography, a precise and patient-specific free flap surgery for autologous breast reconstruction is possible independent of perforator location.

Calcium, magnesium and aluminium ions as decontaminating agents against dermal fluoride absorption following hydrofluoric acid exposure.

The fluoride ions of the industrially largely irreplaceable, locally corrosive hydrofluoric acid (HF) can scavenge cations in biological tissues, which explains their high toxic potential, and also leads to local acidification through proton release. The influence of three complexing agents, calcium (Ca2+) gluconate (as 2.5% Ca2+gel and individually (2.84%) or commercially (10%) formulated Ca2+solution), magnesium (Mg2+) gluconate (2.84%) solution and aluminium (Al3+) solution (Hexafluorine®, pure and diluted) on the absorption of fluoride following HF exposure (1-3 min, 100 µl, 30%/0.64 cm2) through human skin was investigated in an ex-vivo diffusion cell model. Fluoride absorption was assessed over 6-24 h and analysed with a fluoride electrode. Decreasing the contamination time reduced the fluoride absorption distinctly which was further reduced by the application of fluoride-binding decontamination agents (Ca2+, Mg2+, Al3+) or water alone without being significantly different. Ca2+ appeared slightly more effective than Mg2+ in reducing fluoride absorption. Moreover, the addition of pH adjusting buffer promoted the decontamination efficacy. Fluoride-binding agents can facilitate the decontamination of dermal HF exposure. However, prompt decontamination appeared to be the key to successful limitation of fluoride absorption and pushes the choice of decontamination agent almost into the background.

Impact of physiologically relevant temperatures on dermal absorption of active substances - an ex-vivo study in human skin.

Skin temperature plays a certain role in the dermal absorption of substances, but the extent and mechanisms of skin temperatures-induced modulation in ranges caused by physiological thermoregulation or environmental conditions are largely unknown. The influence of dermal temperature on the absorption of the model lipophilic compound (anisole) and the model hydrophilic compounds (1,4-dioxane, ethanol) through human skin was investigated at three dermal temperatures (25, 32 and 39 °C) in an ex-vivo diffusion cell model. The substances were applied to the skin and transdermal penetration was monitored. All substances showed temperature dependent variations in their penetration behavior (3 h: 25-39 °C: 202-275% increase in cumulative, transdermally penetrated amounts). The relative differences in absorption in relation to temperature were greatest within 45 min after exposure (25-39 °C: 347-653% rise in cumulated penetration), although absolute amounts absorbed were small (45 min vs. 3 h: 4.5-14.5%). Regardless of blood circulation, skin temperature significantly influences the amount and kinetics of dermal absorption. Substance-dependent, temperature-related changes of the lipid layer order or the porous pathway may facilitate penetration. The early-stage modulation of transdermal penetration indicates transappendageal absorption, which may be relevant for short-term exposures. For both, toxicological evaluation and perfusion cell studies, it is important to consider the thermal influence on absorption or to perform the latter at a standardized temperature (32±1 °C).

Long-term studies on the integration of acellular porcine dermis as an implant shell and the effect on capsular fibrosis around silicone implants in a rat model.

Acellular dermal matrices have recently increasingly been used in alloplastic breast reconstruction with silicone breast implants. Among these matrices, acellular porcine dermis (APD) is frequently applied, but long-term data on tissue integration and capsular fibrosis formation are still missing. Silicone prostheses with (group A) and without (group B) APD as an implant-covering shell were implanted in male Lewis rats. At 3, 12, and 52 weeks after implantation, the constructs were explanted. Molecular biological and immunohistochemical analyses were performed afterwards. On comparing the collagenous layer and the newly formed myofibroblast-rich layer around the implants of both groups, it became apparent that in group A, these layers were thinner, followed by a lower expression of TGFß1 after 12 and 52 weeks. Further, in this group, at the endpoint of 52 weeks, a lower amount of CD68-positive cells in the collagenous and myofibroblast-rich layers were observed and the expression of TNFα was reduced, while the number of Ki67-positive cells was significantly higher with time. Furthermore, MMP1 expression in group A was lower than that in group B, and the calculated ratio of MMP1:TIMP1 expression was higher. The long-term results clearly show a reduction in inflammatory and fibrotic tissue reaction when APD is used to cover silicone prostheses. These experimental data will be of considerable importance for implant-based breast surgery, as they indicate a potential benefit in the reduction of capsular fibrosis formation of an interposition of APD between the recipient and the silicone implant.

Scalp reconstruction: A 10-year retrospective study.

Scalp reconstruction is a challenging task for the reconstructive surgeon. In consideration of the anatomical and cosmetic characteristics, the defect depth and size, an armamentarium of reconstructive procedures ranging from skin grafts over local flaps to free tissue transfer has been described. In this 10-year retrospective study, 85 operative procedures for scalp reconstruction were performed at our department. The underlying entity, defect size/depth, reconstructive procedure, complications, and mean hospital stay were analyzed. In most cases, scalp reconstruction was necessary after oncologic resection (67%) or radiation therapy (16%). A total of 85 operative procedures were performed for scalp reconstruction including local flaps (n = 50), free tissue transfer (n = 18), and skin grafts (n = 17). Regarding the complication rate, we could detect an overall major complication rate of 16.5% with one free flap loss. Briefly, local flaps are an adequate and safe procedure for limited scalp defects. In the case of extensive scalp defects affecting the calvarium, prior multiple surgical interventions and/or radiation, we prefer free tissue transfer.

Treatment of large femoral bone defects--15-year experiences with the cementless Bicontact revision stem with distal interlocking.

AIM: With the steady growth in the number of hip arthroplasty revision operations, the concept and long-term results of the Bicontact revision stem with distal interlocking for the treatment of extensive femoral bone defects were investigated in this prospective study. METHOD: The first 156 stem revision operations performed between January 1992 and December 2002 were evaluated. The indication for operation was aseptic loosening in 133, stem fracture in 14, recurrent dislocation in 2 and reimplantation following Girdlestone removal of a septic prosthesis in 7. The cup component was revised at the same time in 74 cases. RESULTS: Higher-grade femoral bone defects were found intraoperatively in 66 %. The average age of the patients was 71.4 (34 - 88) years at operation and 76.9 (44 - 94) years at the last follow-up. The average period until follow-up, re-revision or loss to follow-up was 5.54 (0.1 - 14.9) years. The clinical and radiological follow-up rate (with reference to the total number of patients) was 35 % (55 von 156), and 51 % (55 of 107) with reference to patients still living. The median Harris Hip Score was 63.7 points. In the observation period, 12 stems were exchanged for a cemented standard stem, 5 stems were removed because of infection and 2 stems were revised because of periprosthetic fracture. The calculated survival rate for the stems after 14.9 years was 85.9 %. CONCLUSION: The 15-year results confirm the biomechanical concept of the Bicontact revision stem with optional distal interlocking for the treatment of extensive bone defects in stem revision surgery.