Validation of the ultrasonographic assessment of the femoral trochlea epiphyseal cartilage in foals at osteochondrosis predilected sites with magnetic resonance imaging and histology

Abstract

Ultrasonographic examination of the femoral trochlea permitted accurate evaluation of cartilage thickness, cartilage canal vascular archictecture and ossification front indentation in young foals and is a promising, practical tool for screening subclinical osteochondrosis and monitoring and managing lesions at important clinical sites.

Ultrasonographic screening for subclinical osteochondrosis of the femoral trochlea in foals (28–166 days old): a prospective farm study

“…These findings were later confirmed by others [19,20]. We have also recently reported that ultrasonography is an accurate tool for assessing the complex epiphyseal structure (ossification front, growth cartilage and vascular architecture) of the LRTF of very young foals [21].…”

“…Contrast-enhanced power doppler ultrasound examination has revealed cartilage ischaemia of the femoral head induced by hip hyperabduction experimentally in piglets [32]. However, we have previously extensively validated the ultrasonographic features of the femoral trochlea epiphyseal cartilage with both histology and sophisticated MRI imaging techniques for vascularity assessment (3T susceptibilityweighted imaging [21]) and are confident that the lesions we observed here are not normal features of development. As this was a field study, a limitation is that no histologic validation of the observed lesions could be performed for obvious reasons.…”

“…The understanding of the normal hyperechogenic pattern of the epiphyseal cartilage-bone interface in the different regions of the trochlea and at various stages of development and on different ultrasonographic views permitted the identification of focal or multifocal semicircular areas that we interpreted as delays of ossification front progression, pathognomonic of early osteochondrosis [9]. We previously validated the accuracy of the ultrasonographic measurements of the cartilage thickness and ossification front indentation in neonatal foals [21]. The current study extends these findings and provides both qualitative and quantitative data of the normal cartilage thickness and ossification front indentation at different ages, in addition to a description of the maturing cartilage canal architecture at this site in a substantial sample of young foals.…”

“…The cartilage thickness (combined articular and epiphyseal cartilage) and the ossification front indentation (ratio of the length of the chondroosseous junction to the width of the subchondral bone) were calculated on transverse images with Image J software d , as described by Martel et al [21]. The cartilage canal patterns (hyperechoic lines or flecks corresponding to the cartilage-vessel interfaces [21] were also subjectively assessed on sagittal and transverse images. The archived sonograms were evaluated for evidence of subclinical osteochondrosis lesions by consensual agreement of two observers.…”

Clinical insights: Recent developments in equine articular disease (2016–2018)

“…The use of ultrasonography to define femoropatellar developmental pathology was compared with magnetic resonance imaging (MRI) and histology in cadaver limbs. This study confirmed that ultrasonography could define the cartilage thickness, cartilage vascular canal architecture and ossification front indentation, and concluded that ultrasound was a practical tool for screening of subclinical osteochondrosis . A follow‐up clinical study was performed to describe the use of ultrasonography to screen a cohort of 46 foals for osteochondrosis on a farm, as well as to document the normal ultrasonographic features of the lateral trochlear ridge of the femur through development.…”