Regional differences in statistical geometry of endothelial dense granules in human extremity veins

Vicious Circle With Venous Hypertension, Irregular Flow, Pathological Venous Wall Remodeling, and Valve Destruction in Chronic Venous Disease: A Review

Substantial advances occurred in phlebological practice in the last two decades. With the use of modern diagnostic equipment, the patients' venous hemodynamics can be examined in detail in everyday practice. Application of venous segments for arterial bypasses motivated studies on the effect of hemodynamic load on the venous wall. New animal models have been developed to study hemodynamic effects on the venous system. In vivo and in vitro studies revealed cellular phase transitions of venous endothelial, smooth muscle, and fibroblastic cells and changes in connective tissue composition, under hemodynamic load and at different locations of the chronically diseased venous system. This review is an attempt to integrate our knowledge from epidemiology, paleoanthropology and anthropology, clinical and experimental hemodynamic studies, histology, cell physiology, cell pathology, and molecular biology on the complex pathomechanism of this frequent disease. Our conclusion is that the disease is initiated by limited genetic adaptation of mankind not to bipedalism but to bipedalism in the unmoving standing or sitting position. In the course of the disease several pathologic vicious circles emerge, sustained venous hypertension inducing cellular phase transitions, chronic wall inflammation, apoptosis of cells, pathologic dilation, and valvular damage which, in turn, further aggravate the venous hypertension.

Comparison of perioperative complications of pedicled island flap in reconstruction of extremities

PURPOSE

The aim of this study was to analyze the differences in perioperative complications for pedicled island flaps in the reconstruction of extremities and to identify the factors contributing to pedicled island flap necrosis. Furthermore, the flap indications based on these outcomes are summarized.

METHODS

Based on the inclusion criteria, 228 skin flaps were included in this study. Univariate and multivariate analyses were used to identify the risk factors for pedicled island flap necrosis. Differences in perioperative complications between upper and lower extremities were analyzed using the chi-square test or Fisher's exact test.

RESULTS

The average age of the patients was 38 years. The overall complication rate was 21.93%, including partial flap necrosis (10.09%) and total flap necrosis (5.70%). The overall complication rate and flap necrosis rate in upper extremity reconstruction were significantly lower than the rates in lower extremity reconstruction. Flap area and postoperative wound infection were statistically significant risk factors for pedicled island flap necrosis in extremity reconstruction. Preoperative contamination of the wound bed was a statistically significant risk factor for postoperative wound infection.

CONCLUSIONS

The flap area and postoperative wound infection were both independent risk factors for pedicled island flap necrosis in extremity reconstruction. The causes contributing to the differences in perioperative complications between upper and lower extremities reconstruction included preoperative contamination of the wound bed, postoperative wound infection, and the flap area but were also related to anatomical factors of the skin flap. Pedicled island flaps are more suitable for small- and medium-sized soft tissue defects.