OBJECTIVE To describe type and distribution of tarsal collateral ligament (CL) injuries and to assess the long-term outcome in horses treated conservatively. ANIMALS 78 horses (median age, 7 years [IQR, 4 to 9.75 years]) of different breeds and disciplines. PROCEDURES Retrospective analysis (2000 through 2020) of horses with tarsal CL lesions diagnosed on ultrasound. The resting time, ability to return to work, and performance level after the injury were compared between horses having a single ligament (group S) or multiple ligaments (group M) affected and according to the case severity. RESULTS Most of the horses (57/78) presented a single CL injury, while 21 had multiple CLs affected simultaneously, for a total of 108 CLs injured and 111 lesions. In both groups, the short lateral CL (SLCL) was the most commonly affected (44/108), followed by the long medial CL (LMCL; 27/108). Enthesopathies (72.1%) were more frequent than desmopathies alone (27.9%) and involved mostly the proximal insertion of the SLCL and the distal attachment of the LMCL. Conservative treatment (n = 62) consisted mainly of stall rest. The median resting time (120 days [IQR, 60 to 180 days]) did not significantly differ between the 2 groups (group S vs M) or according to the severity. Most horses (50/62) were able to return to work within 6 months. Horses that did not return (12/62) were more likely to have severe lesions (P = .01). Thirty-eight horses were able to perform at a level equal to or higher than before the injury. CLINICAL RELEVANCE This study highlights the importance of thorough ultrasound assessment of tarsal CL injuries and demonstrates that conservative management is a viable option to allow these horses to return to previous performance level.

Summary Background Squamous cell carcinoma is the most common pharyngeal neoplasm but is poorly documented with diagnostic imaging in veterinary literature. Objectives To describe the diagnostic imaging findings in horses with confirmed pharyngeal squamous cell carcinoma. Study design Retrospective case series. Methods Horses with a definitive diagnosis of pharyngeal squamous cell carcinoma based on in situ biopsy and/or cytology were identified in 2 different centres. Multi‐modality imaging findings are reported. Results Six equids were included. On radiographic examination, increased pharyngeal opacity and reduction of pharyngeal lumen were observed in all horses, centred on the oropharynx (three cases), the laryngopharynx (two cases) or the nasopharynx (one case). A clearly delineated mass was visualised in four cases. Additional radiographic findings were border effacement of the epiglottis (5/6) or soft palate (3/6), thickening of the pharyngeal walls (4/6) or soft palate (3/6) and suspected retropharyngeal lymphadenomegaly (3/6). Ultrasonography was useful to highlight retropharyngeal (4/6) and mandibular (4/6) lymphadenopathy suggestive of metastatic dissemination. Computed tomographic images were available for two horses and detected bone lysis not visible on radiographs. Main limitations The number of cases was low, and computed tomography was not realised in all cases. Conclusions Findings support the usefulness of radiography and ultrasonography in horses with suspected pharyngeal neoplasia for a first‐line imaging diagnosis, in particular when endoscopy is impaired by a mass effect or dyspnoea. Computed tomography gives a more accurate assessment of bone involvement.

SummaryBackgroundLymph nodes are routinely assessed ultrasonographically in humans and small animals. The ultrasonographic assessment of equine lymph nodes has only been sporadically reported.ObjectivesThe aims of this study were to establish anatomical landmarks, ultrasonographic technique and normal ultrasonographic appearance of clinically relevant equine lymph nodes difficult to assess by palpation and to provide a useful reference for equine practitioners.Study designThis was prospective observational study.MethodsMedial retropharyngeal, cranial and caudal deep cervical, and caecal lymph nodes were visualised using transcutaneous ultrasonography in 19 clinically healthy horses, and lymph nodes of the iliosacral lymphocentre were visualised using transrectal ultrasonography in nine horses with no metabolic or infectious disorders. Anatomical landmarks, size and echogenicity were recorded.ResultsA total of 268 lymph nodes were visualised and measured in 25 horses. Lymph nodes were ovoid with regular contour and homogeneous parenchyma, hypoechoic to isoechoic to the surrounding tissue. The visualised lymph nodes of the sacroiliac lymphocentre were the smallest (mean ± standard deviation: 2.4 ± 0.9 × 5.9 ± 1.8 mm), and the largest were the caudal deep cervical lymph nodes (mean ± standard deviation: 5.1 ± 1.9 × 10.9 ± 5.6 mm). The short‐to‐long‐axis ratio varied from 0.44 to 0.60 among the lymph nodes examined.Main limitationsNormality of lymph nodes was not confirmed by histopathology.ConclusionsThis study describes the ultrasonographic technique, anatomical landmarks and appearance of presumptively normal medial retropharyngeal, cranial and caudal deep cervical, caecal lymph nodes and caudal lymph nodes of the iliosacral lymphocentre.