Muscle-only versus chimeric musculocutaneous gastrocnemius pedicled flap in complex orthoplastic reconstructions of the knee region: A retrospective study.

BACKGROUND: The knee region represents a challenging area of soft tissue reconstruction. Specifically, in the context of total knee arthroplasty (TKA) or following high-energy trauma with fractures and hardware fixation, soft tissue defects can expose critical structures such as joint, bone or tendon, besides the implant/plates themselves, with dramatic consequences in terms of postoperative infection and hardware contamination. METHODS: A retrospective study was conducted on a prospectively maintained database from January 2016 to February 2021. Inclusion criteria involved all patients who underwent an implant-associated infection of the knee and upper third of the leg coupled with a soft tissue reconstruction (STR) using the traditional gastrocnemius muscle (GM) pedicled flap or the chimeric GM-MSAP (medial sural artery perforator) flap. RESULTS: Thirty-eight patients were included (group A, GM flap, 22 patients; group B, chimeric GM-MSAP flap, 16 patients). No statistically significant differences were detected in terms of age, comorbidities, defect size, follow-up, and flap complications. A statistically significant difference was seen among the groups in terms of successful flap re-raise (required because of a persistent infection of the implant or in a two-stage procedure setting, including the use of a cemented spacer) in favour of the GM-MSAP group. CONCLUSION: The chimeric GM-MSAP, being safer to reraise if required, can be a significantly more powerful tool in those cases in which a two-stage procedure is planned or when there is a high probability for secondary intervention need, reducing the need to convert to either free flap coverage or amputation.

Low osmolality and shear stress during liposuction impair cell viability in autologous fat grafting.

BACKGROUND: Liposuction and subsequent autologous fat grafting have become essential techniques for fat augmentation in plastic surgery. However, standard harvesting techniques that ensure the survival of adipocytes and stromal vascular fraction (SVF) cells and thus preserve the transplanted fat volume are lacking. In particular, the effect of different parameters of the tumescent solution has not been studied in this context. We hypothesized that the osmolality of the tumescent solution could have a significant effect on the survival of adipocytes and SVF cells. METHODS: We developed two distinct in vitro models based on freshly harvested excision fat from patients undergoing surgical treatment. First, we investigated the effect of osmolality by incubating excision fat in different tumescent solutions and analyzed the total cell survival and the differentiation potential of SVF cells. Vital whole-mount staining, isolation yield of SVF cells, clonogenicity, and osteogenic and adipogenic differentiation capacities were analyzed. Second, we addressed the additional effect of mechanical stress by simulating a liposuction on pieces of excision fat after incubation with the tumescent solutions. RESULTS: Osmolality of the tumescent solution by itself did not have a significant effect on adipocyte and SVF viability or SVF differentiation. However, when osmolality was combined with liposuction, a significant trend toward lower viability and more lipid droplets with lower osmolality was observed. Especially, SVF viability was significantly lower after liposuction with a hypotonic (150 mOsm/kg) solution. CONCLUSION: This study demonstrates the considerable effect of osmolality during liposuction and may lead to the development of "cell-protective" tumescent solutions.

Pericyte plasticity - comparative investigation of the angiogenic and multilineage potential of pericytes from different human tissues.

Pericyte recruitment is essential for the stability of newly formed vessels. It was also suggested that pericytes represent common ancestor cells giving rise to mesenchymal stem cells (MSCs) in the adult. Here, we systematically investigated pericytes and MSCs from different human tissues in terms of their angiogenic and multilineage differentiation potential in vitro in order to assess the suitability of the different cell types for the regeneration of vascularised tissues. Magnetic-activated cell sorting (MACS®) was used to enrich CD34-CD146+ pericytes from adipose tissue (AT) and bone marrow (BM). The multilineage potential of pericytes was assessed by testing their capability to differentiate towards osteogenic, adipogenic and chondrogenic lineage in vitro. Pericytes and endothelial cells were co-seeded on Matrigel™ and the formation of tube-like structures was examined to study the angiogenic potential of pericytes. MSCs from AT and BM were used as controls. CD34-CD146+ cells were successfully enriched from AT and BM. Only BM-derived cells exhibited trilineage differentiation potential. AT-derived cells displayed poor chondrogenic differentiation upon stimulation with transforming growth factor-ß1. Interestingly, osteogenic differentiation was more efficient in AT-PC and BM-PC compared to the respective full MSC population. Matrigel™ assays revealed that pericytes from all tissues integrated into tube-like structures. We show that MACS®-enriched pericytes from BM and AT have the potential to regenerate tissues of different mesenchymal lineages and support neovascularisation. MACS® represents a simple enrichment strategy of cells, which is of particular interest for clinical application. Finally, our results suggest that the regenerative potential of pericytes depends on their tissue origin, which is an important consideration for future studies.

[Long-term outcome after surgical treatment of breast asymmetry: analysis of the patient's perspective in 51 cases]. / Langzeitresultate nach chirurgischer Behandlung von Brustasymmetrien aus Sicht der Patientinnen: Eine Analyse von 51 Fällen.

INTRODUCTION: Literature provides 3 studies only investigating the long-term outcome after surgical correction of breast asymmetry. The goal of this study was to analyse from a patient's perspective, which factors influence postoperative satisfaction most. PATIENTS AND METHODS: All patients undergoing surgical treatment for breast asymmetry between 2000 and 2009 were included. With help of the visual analogue scale the patients conducted a subjective assessment of their own long-term result using the following parameters: overall satisfaction, symmetry, size, shape, scarring and sensitivity. Anthropometric measurements of the breasts followed. RESULTS: 51 patients (80% follow-up) were seen 2-11 (mean 5±2.5) years postoperatively. The following mean values were recorded for overall satisfaction 8.31 (±1.91), symmetry 7.86 (±2.25), size 8.42 (±1.93), shape 8.12 (±2.03), scarring 7.82 (±1.94) and sensitivity 7.92 (±2.19). Overall satisfaction increased significantly with good scores for the parameters symmetry [p=0.01] and shape [p=0.048]. Neither size [p=0.46] nor scarring [p=0.69] nor sensitivity [p=0.34] had a statistically significant influence on overall satisfaction. Furthermore, overall satisfaction did not depend on the surgical technique, preoperative size, preoperative asymmetry, age of the patient at time of surgery, period of time between the operation and the assessment, resected weight (absolute and difference between left and right) or on postoperative symmetry of the nipple areola complex. CONCLUSION: In our patients, long-term overall satisfaction after surgical correction of breast asymmetry was primarily dependent on symmetry and shape. Size, scarring and sensitivity did not have a statistically significant influence on postoperative overall satisfaction. This also applied to preoperative size, preoperative extent of asymmetry, age of the patient at time of surgery, surgical technique and the time span between the operation and the assessment.

Assessment of long-term donor-site morbidity after harvesting the latissimus dorsi flap for neonatal myelomeningocele repair.

BACKGROUND AND AIM: The latissimus dorsi flap (LDF) has been employed very successfully over decades to cover large soft-tissue defects. Its donor-site morbidity has been extensively investigated in adults - but not in children - and is considered to be nonrestrictive. The aim of this long-term study was to assess donor-site morbidity with the modified Constant score more than 8 years after coverage of large myelomeningocele (MMC) defects with a reverse latissimus dorsi flap. METHODS: Within the first days after birth, the reverse latissimus dorsi muscle flap was used uni- or bilaterally in three neonates to cover a large MMC defect. Bilateral shoulder function was tested more than 8 years postoperatively according to the modified Constant score. RESULTS: The mean age at follow-up was 11.7 years. None of the patients experienced any pain or shoulder restrictions during normal daily activities. They all managed to position both of their arms comfortably above the head. Forward flexion was normal in all patients as was abduction and external rotation. Dorsal extension was minimally reduced on the operated side. Internal rotation was symmetric in all patients; the extent of active movement varied from excellent to poor. CONCLUSIONS: Our long-term data suggest that there is no specific and significant impairment of shoulder function after using the distally pedicled reverse LDF for neonatal MMC repair.

[One-stage reconstruction of facial defects after tumor resection with the Integra system]. / Integra zur einzeitigen Defektdeckung nach Tumorresektion im Gesichtsbereich.

BACKGROUND: In 2010 excellent aesthetic results after basal cell carcinoma excision and one-stage coverage with Integra without split thickness skin graft (STSG) were published in a series of 10 Asian patients. Our aim in this study was to verify these results in a series of Caucasian patients and evaluate this procedure as a possible new standard. PATIENTS AND METHODS: 6 patients with facial basal cell carcinoma were treated by regular excision with 3 mm safety margins and one-stage coverage with Integra without STSG, followed by a clinical evaluation and fotodocumentation. RESULTS: In 3 patients local infection occurred with a complete loss of the Integra. 2 out of these 3 patients showed an unaesthetic scar and are considering another surgical approach for correction. The other 3 patients had an uneventful course, unfortunately 2 out of these patients (67%) developed an unaesthetic scar as well and are also considering surgical correction. CONCLUSION: Because of aesthetically unsatisfactory results and high infection rates we abandoned this procedure after 6 patients only. Our standard remains excision with 3 mm safety margins, histological analysis and one-stage repair with local facial flaps.

[The influence of ulnar variance on the healing of scaphoid fractures]. / Einfluss der Ulnavarianz auf die Kahnbein-Frakturheilung.

The recent literature shows that a negative ulnar variance could pose a risk factor for scaphoid fractures.The aim of the current study was to determine whether the ulnar variance also affects the healing of a scaphoid fracture.2 cohorts of 50 patients each, with either a scaphoid fracture or a non-union, were retrospectively compared. The ulnar variance was measured on the X-rays using the Gelberman method.The average value of the ulnar variance in patients with a scaphoid fracture was -1.0 mm. The negative ulnar variance was measured in 64% of the patients. In the second group with scaphoid non-union, the average value of ulnar variance was -0.8 mm. The negative ulnar variance was similarly high, in 68% of the patients. Our results demonstrated almost identical values in both groups with regard to ulnar variance or its distribution, neutral, negative or positive, without statistical significance.Thus, we can exclude the negative ulnar variance as a risk factor for the development of non-union in cases of scaphoid fractures.

[Connection between hyponatriemia and local herpes in an old lady?]. / Die Hyponatriämie der Frau L.

We report the case of a 84 year old patient who developed a syndrome of inappropriate antidiuretic hormone secretion (SIADH) with severe hyponatremia in the context of a localized herpes zoster L1/2. This is a rare but known complication of localized varizella zoster infection. Under water restriction and salt administration the hyponatremia was corrected slowly. One month after hospital discharge the patient showed a normal sodium value without diet.

Primmorphs from seven marine sponges: formation and structure.

Primmorphs were obtained from seven different marine sponges: Stylissa massa, Suberites domuncula, Pseudosuberites aff. andrewsi, Geodia cydonium, Axinella polypoides, Halichondria panicea and Haliclona oculata. The formation process and the ultra structure of primmorphs were studied. A positive correlation was found between the initial sponge-cell concentration and the size of the primmorphs. By scanning electron microscopy (SEM) it was observed that the primmorphs are very densely packed sphere-shaped aggregates with a continuous pinacoderm (skin cell layer) covered by a smooth, cuticle-like structure. In the presence of amphotericin, or a cocktail of antibiotics (kanamycin, gentamycin, tylosin and tetracyclin), no primmorphs were formed, while gentamycin or a mixture of penicillin and streptomycin did not influence the formation of primmorphs. The addition of penicillin and streptomycin was, in most cases, sufficient to prevent bacterial contamination, while fungal growth was unaffected.

Development of in vivo sponge cultures: particle feeding by the tropical sponge Pseudosuberites aff. andrewsi.

The rate of food particle uptake of the tropical sponge Pseudosuberites aff. andrewsi was studied in relation to particle concentrations and particle size. A range of different concentrations of either the marine microalga Dunaliella tertiolecta (approximately 5-8 microm) or the marine cyanobacterium Synechococcus sp. (approximately 1 microm) was supplied to the sponges. D. tertiolecta had a pronounced effect on the filtration activity of the sponges: at concentrations higher than approximately 4 x 10(5) cells/cm(3), the filtration rates dropped dramatically. Such a clear effect was not found for Synechococcus sp. The results further showed that the maximal amount of food (when expressed in organic carbon) that can be taken up per cubic centimeter of sponge volume per unit of time should in principle be sufficient to enable growth (irrespective of the food particle type). At the maximal food particle concentration that did not affect the filtration rates, the uptake of organic carbon is already highly in excess of the amount of organic carbon that the sponges need to cope with their respiratory demand. Based on these findings, a series of growth experiments was carried out in which the sponges were subjected to a constant concentration of different types of food particles (Synechococcus sp. and the microalgae Chlorella sorokiniana and Nannochloropsis sp). Although initial growth was sometimes observed, continuous growth at a constant rate could not be obtained. It is concluded that qualitative aspects of feeding rather than quantitative aspects are the key to successful in vivo sponge culture.

Cultivation of Marine Sponges.

There is increasing interest in biotechnological production of marine sponge biomass owing to the discovery of many commercially important secondary metabolites in this group of animals. In this article, different approaches to producing sponge biomass are reviewed, and several factors that possibly influence culture success are evaluated. In situ sponge aquacultures, based on old methods for producing commercial bath sponges, are still the easiest and least expensive way to obtain sponge biomass in bulk. However, success of cultivation with this method strongly depends on the unpredictable and often suboptimal natural environment. Hence, a better-defined production system would be desirable. Some progress has been made with culturing sponges in semicontrolled systems, but these still use unfiltered natural seawater. Cultivation of sponges under completely controlled conditions has remained a problem. When designing an in vitro cultivation method, it is important to determine both qualitatively and quantitatively the nutritional demands of the species that is to be cultured. An adequate supply of food seems to be the key to successful sponge culture. Recently, some progress has been made with sponge cell cultures. The advantage of cell cultures is that they are completely controlled and can easily be manipulated for optimal production of the target metabolites. However, this technique is still in its infancy: a continuous cell line has yet to be established. Axenic cultures of sponge aggregates (primmorphs) may provide an alternative to cell culture. Some sponge metabolites are, in fact, produced by endosymbiotic bacteria or algae that live in the sponge tissue. Only a few of these endosymbionts have been cultivated so far. The biotechnology for the production of sponge metabolites needs further development. Research efforts should be continued to enable commercial exploitation of this valuable natural resource in the near future.

[A new apparatus for the continuous measurement of the concentration of anaesthetic vapours (author's transl)]. / Ein neues Gerät zur kontinuierlichen Messung von Narkosedämpfen.

A new apparatus is described for the continuous on-line estimation of the concentration of anaesthetic vapours. The results obtained with the apparatus for halothane were compared with those registered by a mass spectrometer; there was excellent agreement (r = 0.999). The equipment is very manageable and has already proved its value is anaesthetic practice.