The congenital clubfoot – immunohistological analysis of the extracellular matrix

Abstract

Purpose: Congenital clubfoot is one of the most common limb disorders in humans and its etiology is still unclear. In order to better understand the pathogenesis of patients with primary clubfoot, we examined whether there are quantitative changes in the extracellular matrix (ECM; based on common interstitial collagens [C] like CI and CIII, microfilamentous collagens like CVI, noncollagenous proteins like undulin, and enzymes like matrixmetalloproteinase [MMP]-2 and tissue inhibitor of matrixmetalloproteinase [TIMP]-2 that are known to play a role in fibrogenesis and fibrolysis) of muscles involved in the foot deformity of patients with primary clubfoot corresponding to fibrosis. Patients and methods: Thirty patients (age ranging from 4 months to 5 years and 7 months) with primary clubfoot were examined (23 male and 7 female patients), among whom 18 patients were affected on one side and 12 affected on both sides. Twenty-five biopsies were taken during the first operative foot correction (Crawford-McKay) and 5 in the context of relapses. Muscle biopsies were taken from the muscles involved in the defect (Musculus [M.] gastrocnemius and M. tibialis anterior) and from the M. vastus lateralis of the M. quadriceps femoris, which were treated as healthy comparison muscles. Quantitative analysis of the components of the ECM was performed using a computer-assisted fibrosis measurement of the immunohistochemically processed tissue samples. Results: We found higher values for M. gastrocnemius for CI, CIII, CVI and undulin in comparison with M. vastus lateralis. However, values for TIMP-2 were reduced. We found no significant differences for the components of M. tibialis anterior and M. vastus lateralis. There were no quantitative differences between male and female or between patients affected on one side and both sides. In patients who underwent relapse surgery, CI, CIII, CVI, and undulin of the gastrocnemius were significantly higher, while TIMP-2 was significantly lower. Conclusion:In the present study, we found manifest fibrosis in gastrocnemius due to quantitative changes in the ECM. In contrast to other studies, we found increasing fibrosis not just in contracted tissues but also in the muscle itself. Further studies are needed to clarify whether these changes are primarily responsible for the malfunction or whether they occur secondarily in the consequence of the dysfunction. Keywords: pes equinovarus, clubfoot, extracellular matrix, fibrosis, collagens, TIMP-2 IntroductionCongenital clubfoot is one of the most common limb disorders in humans with a prevalence of 1-2/1000 live births among Caucasians.1 The deformity appears with an adductus of the forefoot, a cavus of the midfoot, and an equinovarus of the hindfoot, for which there is a wide variation in clinical severity.2 There are many theories

Minoxidil decreases collagen I deposition and tissue-like contraction in clubfoot-derived cells: a way to improve conservative treatment of relapsed clubfoot?

“…Older histological and electron microscopy studies have suggested the existence of fibrotic changes in tissue biopsies extracted from the clubfoot deformity- [13][14][15] . More recently published proteomic and molecular studies have revealed changes in the amount of collagen type I, III, VI, and profibrotic cytokines, such as transforming growth factor (TGF-β) and plateletderived growth factor (PDGF) in tissue from clubfoot medial side [16][17][18] and also in m. gastrocnemius 19 . These studies have therefore confirmed the presence of fibrosis in clubfoot.…”

Integrated Bioinformatics Analysis Reveals Potential Pathway Biomarkers and Their Interactions for Clubfoot

“…We found that MMP7, CASP3, and COL9A1 genes were involved in the progress of collagen formation and degradation of the extracellular matrix. In addition, interleukin-13 (IL-13) may induce myofibroblasts to produce ECM which indicates that excess stimulation induced by chronic inflammation promotes excessive accumulation of ECM [ 35 ]. These bioinformatics results supported the previous hypothesis that ECM abnormality and immune responses participated in the etiopathogenetic mechanism of clubfoot.…”

Pé torto congênito – O método Ponseti é a solução definitiva?

“…This area presents a rigid nature with hyperproduction of extracellular matrix components. 15 To fulfill the lack of prognosis, other possible methods to predict recurrence have been tested. Recently, a low eversor muscle activity has been considered as a significant recurrence parameter in CCF.…”