Cell interactions in post-traumatic fibrosis

The incidence of postoperative flare reaction and tissue complications in Dupuytren's disease using tension-free immobilization

PURPOSE

Open fasciectomy represents a standard treatment of Dupuytren's disease. Although patients are commonly immobilized in extension to prevent postoperative contracture formation, immobilizing the extremity under tension may precipitate a flare reaction and scar-related complications. This study explores the incidence of flare reaction and other complications with postoperative tension-free splinting after fasciectomy for Dupuytren's contracture.

METHODS

We retrospectively reviewed patients' charts that consisted of 228 procedures in 191 patients who underwent surgery by the senior author between 2000 and 2010. Postoperative notes were reviewed for wound healing problems, scar appearance, flare reaction, and complications. The grading system defined by Evans et al. was used to standardize flare reaction and scar complications.

RESULTS

Using tension-free splinting, the incidence of flare reaction was 3.5 % (8/228). The eight patients that had flare reactions had mild involvement, and no severe reaction was observed. Fifteen patients had hypertrophic scars, eight had hypersensitive scars, and six had recurrent contractures.

CONCLUSIONS

The incidence of flare reaction using tension-free immobilization postoperatively was low in our study. According to our findings, wound healing problems are rare when tensionless splinting is utilized. Type of study/level of evidence Case series, Level IV, Therapeutic study.

Phagocytosis of aged human neutrophils by macrophages is mediated by a novel "charge-sensitive" recognition mechanism

The removal of neutrophils and their histotoxic contents from the inflamed site is a prerequisite for resolution of tissue injury, and a point at which factors critical to the pathogenesis of chronic inflammation may act. Engulfment of intact, senescent neutrophils by macrophages represents an important neutrophil disposal process. In this study the mechanism by which human monocyte-derived macrophages (M phi) recognized and ingested human neutrophils that had been aged in culture was studied using an in vitro phagocytic assay. Inhibition of M phi receptors for Ig Fc and the opsonic complement fragments C3b and iC3b with MAbs to M phi FcR, CR1, CR3, and CR4 had no effect on recognition, and the pattern of inhibition observed when polyanions were included in the medium at 1 mg/ml was different from that reported for the M phi receptor for protein advanced glycosylation end products (AGE), indicating a recognition mechanism different from those proposed for M phi phagocytosis of senescent erythrocytes. Furthermore, although aging neutrophils undergo programmed cell death (or apoptosis), which is directly related to recognition by M phi, the pattern of inhibition observed with monosaccharides was different from that reported to inhibit the binding of apoptotic mouse thymocytes to isologous M phi. By contrast, evidence was obtained for a novel recognition mechanism inhibitable by cationic sugars and amino acids in a charge-dependent fashion, and directly modulated by pH but not affected by inhibitors of the mannose-6-phosphate, sheep erythrocyte, mannosyl-fucosyl, asialoglycoprotein, and scavenger receptors of the macrophage. These observations suggest that hydrogen ions and charged molecules may modulate M phi uptake of senescent neutrophils at inflamed sites, and that recognition itself may involve charged structures on the cells.