Comparison of radiographic changes of the proximal third metacarpal and metatarsal bones in horses with and without proximal suspensory desmitis

Abstract

Summary: Medical records of horses examined from 1994 to 2011 at the Equine Hospital, Vetsuisse Faculty, University of Zurich, because of proximal suspensory desmitis (PSD) were reviewed. Radiographic changes visible on dorsopalmar and dorsoplantar projections of the proximal third metacarpal/metatarsal bone (MCIII/MTIII) were analysed with respect to localisation, degree of increased radiopacity, length, width and pattern of radiopacity in relation to sex, age, breed, duration and degree of lameness and affected limb of the horses. Results were compared with those from sound control horses. Horses with PSD had increased radiopacity, which was significantly more prevalent medially than laterally in the forelimbs (p < 0.05) and more prevalent laterally than medially in the hindlimbs (p < 0.05). The width of the area of increased radiopacity was significantly greater in the forelimbs than in the hindlimbs (p < 0.05). The pattern of increased radiopacity was diffuse in 102 (85.7 %) horses and multifocal in the remaining 17 (14.3 %). 35.3 % (n = 6) of multifocal changes were detected on one of the front limbs, whereas 74.7 % (n =11) were diagnosed on the hind limbs. Mildly increased diffuse radiopacity, with a distribution pattern comparable to cases with PSD was detected in 15 of 60 control horses. In comparison to control cases, the degree of increased diffuse radiopacity was significant more pronounced in horses with PSD (p < 0.001). The multifocal pattern of increased radiopacity could not be detected in any of the control horses. The results aid in the interpretation of radiographic changes seen in horses with PSD. Whereas a diffuse increased radiopacity of the proximal MCIII/MTIII needs to be interpreted with caution, as a mild degree may be seen in sound horses, the multifocal distribution pattern seems to be unique feature of horses with PSD.Keywords: proximal suspensory desmitis / PSD / radiographic changes / suspensory ligament / desmitis Vergleich von röntgenologischen Veränderungen im Bereich des proximalen Metakarpus und Metatarsus bei Pferden mit und ohne Desmopathie des FesselträgerursprungsIn der vorliegenden Studie wurden die Patientendaten von Pferden, die im Zeitraum von 1994 bis 2011 in der Pferdeklinik des Departements für Pferde der Vetsuisse-Fakultät, Universität Zürich wegen einer Desmitis des Fesseltägerursprungs vorgestellt wurden, retrospektiv evaluiert. Die im dorso-palmaren, bzw. dorso-plantaren Strahlengang sichtbar vermehrte Röntgendichte im Bereich des proximalen Metakarpus III/Metatarsus III wurde nach ihrer Lokalisation, Ausdehnung (Länge und Breite), Schweregrad der Veränderungen und Erscheinungsbild ausgewertet. Zudem wurden das Geschlecht, das Alter, die Rasse, die Dauer der klinischen Symptomatik, die erkrankte Gliedmaße und der Lahmheitsgrad ausgewertet. Die Ergebnisse wurden mit einer Kontrollgruppe verglichen. Für die Kontrollgruppe wurden 30 Röntgenbilder eines Karpus und 30 Röntgenbilder eines Tarus je in der dorsopalmaren/plantaren Projektion nach dem gleichen Schema ausge...

Radiographic changes of the proximal third metatarsal bone do not predict presence or severity of proximal suspensory desmopathy in a predominately Quarter Horse population

“…Our results demonstrate that the presence of radiographic changes, including sclerosis and lucent regions, in proximal MTIII This differed from recent work comparing radiographic changes and ultrasonography where increased radiopacity of proximal MTIII was found to be more frequently located in the lateral aspect. 13 In addition, multifocal radiopacity was more frequent in horses with PSD and not seen in any control horse leading to the conclusion that a multifocal pattern could represent pathognomonic features of PSD. 13 The difference between studies may be due to breed, discipline or age differences of each population.…”

“…13 In addition, multifocal radiopacity was more frequent in horses with PSD and not seen in any control horse leading to the conclusion that a multifocal pattern could represent pathognomonic features of PSD. 13 The difference between studies may be due to breed, discipline or age differences of each population. horses with severe lameness had significant tarsal pathology (data not shown).…”

“…4,7 Comparisons of the proximal metatarsal region have been made between radiography and nuclear scintigraphy, radiography and ultrasonography and ultrasound and magnetic resonance imaging. 4,8,9,[11][12][13][14] A recent comparison between radiographic and ultrasonographic findings of the proximal metacarpus and metatarsus has found that horses with PSD had more increased radiopacity in the lateral aspect of the metatarsus, and a multifocal distribution pattern was more common in hindlimbs with PSD. 13 Limited comparisons with a low number of clinically affected horses have been made between radiographic examination and MRI.…”

“…4,8,9,[11][12][13][14] A recent comparison between radiographic and ultrasonographic findings of the proximal metacarpus and metatarsus has found that horses with PSD had more increased radiopacity in the lateral aspect of the metatarsus, and a multifocal distribution pattern was more common in hindlimbs with PSD. 13 Limited comparisons with a low number of clinically affected horses have been made between radiographic examination and MRI. 7 A better understanding of radiographic lesions compared with MRI findings will aid in the interpretation of radiographic studies for practitioners.…”

“…Magnetic resonance imaging findings of PSD include enlargement, altered fat and muscle bundle architecture and areas of abnormal increased signal 4,7 . Comparisons of the proximal metatarsal region have been made between radiography and nuclear scintigraphy, radiography and ultrasonography and ultrasound and magnetic resonance imaging 4,8,9,11‐14 . A recent comparison between radiographic and ultrasonographic findings of the proximal metacarpus and metatarsus has found that horses with PSD had more increased radiopacity in the lateral aspect of the metatarsus, and a multifocal distribution pattern was more common in hindlimbs with PSD 13 .…”