Ultrasonography in Canine Carpal Disorders.

Abstract

Ultrasonographic studies of canine carpal disorders are scarce and typically limited to case reports or evaluations of single structures. This prospective, single-center study characterized ultrasonographic findings in canine carpal disorders confirmed by a composite reference standard and clinical follow-up, and it assessed the diagnostic role of high-frequency musculoskeletal ultrasound in relation to radiography and selectively performed cross-sectional imaging. Forty-eight carpi in 41 dogs were evaluated. This study represents the first ultrasound case series across the spectrum of canine carpal disorders. Musculotendinous disorders were most common (n = 30/48; 63%), followed by inflammatory arthropathy, neoplasia, and bone lesions (each 6/48; 13%). Ultrasound enabled compartmental localization of swelling and structural characterization of soft tissue abnormalities. Swelling distribution correlated with the underlying disorder in 46 of 48 (96%) carpi; subcutaneous thickening (n = 27/48; 56%) was frequent but nonspecific. Stenosing tenosynovitis of the abductor pollicis longus was the most common individual diagnosis (n = 16/48; 33%). Carpal effusion was identified sonographically and associated with dorsal displacement of the antebrachiocarpal fat pad. Ultrasonography did not allow reliable benign-malignant classification of mass lesions; therefore, definitive classification requires tissue sampling. In the subset undergoing cross-sectional imaging, CT or MRI primarily refined lesion extent and osseous detail, particularly in bone lesions including fractures, but did not consistently alter the primary diagnosis established by combined radiography and ultrasonography. A combined radiographic and ultrasonographic approach is supported as a practical first-line imaging strategy for canine carpal disease, with CT or MRI reserved for selected complex, equivocal, or predominantly osseous cases.