Spondylosis is uncommon but may be a contributor to back pain in the horse.

Summary Desmitis of the origin of the suspensory ligament is a common injury of sport horses; however, it remains a diagnostic challenge. The anatomy of the region can lead to difficulties localising the lameness. Diagnostic imaging may be complicated by overlying structures and the limitations of the imaging modalities readily available. A logical approach to clinical examination, diagnostic analgesia and multimodal imaging can help to overcome these difficulties.

Summary Background Trauma to the foot and distal phalanx are common presenting complaints. In contrast, neoplasia of the distal phalanx or hoof region is rarely reported. Within the foot, keratomas are the most frequently reported neoplasm. The gross and radiographic appearance of keratomas is well documented; however, this is less well established for other neoplasms of the hoof capsule. Objective This paper presents four cases which had clinical and radiographic similarities to keratomas; however, key differences were observed. We aimed to highlight the key differences in imaging findings and clinical progression. Study design Retrospective multicentre case series. Methods Cases identified between 2015 and 2019 with pathological diagnoses of neoplasia within the foot at Purdue University Veterinary teaching hospital and Langford Equine Hospital. Clinical records were examined, and physical examination, imaging, surgical and pathological findings are presented. Results The four cases presented had similarities to keratomas; however, key differences were present. Marked lameness was noted in all three cases with aggressive neoplasia, whereas one case was not lame at presentation but still had a diagnosis of a benign neoplasm. Radiographic examination showed significant lucent areas with poor delineation at the margins and suspected invasion into the distal phalanx. For the two melanomas and the squamous cell carcinoma, deterioration was marked and rapid, ultimately leading to euthanasia. The benign neoplasm was managed successfully for 2 years and lost to follow‐up. Conclusions Although rare, neoplasms other than keratoma do occur in the foot. Careful interpretation of the imaging findings, consideration of additional imaging such as vascular studies or cross‐sectional imaging, and submission of tissue for biopsy are strongly recommended if there is any suspicion of the lesion being anything other than a keratoma.

Summary A 14‐year‐old Connemara cross gelding presented with abnormal respiratory noise and exercise intolerance. Upper airway endoscopy, ultrasonography, radiography and computed tomography revealed a large mass within the left guttural pouch causing marked left dorsal nasopharyngeal collapse and displacement and compression of the right guttural pouch. The horse was subjected to euthanasia and a post‐mortem examination confirmed the above findings. Histological and immunohistochemical examinations of the mass confirmed a diagnosis of guttural pouch leiomyosarcoma, a lesion previously unreported at this site.

The diaphragm is an important respiratory muscle, playing a key role during exercise. In humans, diaphragm thickness increases in response to training and is correlated with inspiratory strength. In order to assess respiratory strength in the horse, new evaluation techniques are required and measurement of diaphragm thickness, in a non-invasive and repeatable manner, is a possible approach. The purposes of this four-part, prospective, pilot study were to develop and describe a repeatable method to measure the diaphragm thickness, using ultrasonography, in Thoroughbred racehorses. A standardized technique was developed whereby the ultrasound transducer was positioned 1 cm below a line between the cranioventral aspect of the tuber coxae and olecranon. The diaphragm thickness was measured on three occasions 1 week apart, by a single observer to determine the intraobserver repeatability, and by a second observer on one occasion to assess interobserver reproducibility. The diaphragm was observed in all intercostal spaces (ICS) from 7 to 17 on the left side, and 6 to 17 on the right side in a single horse. The thickest measurement (1.42 cm), obtained from 11 horses, was at ICS 11 on the left-side during inspiration. The narrowest measurement (0.56 cm) was obtained at ICS 16 on the right-side during expiration. There was no significant difference between the measurements obtained by a single observer on three occasions (P < .05). This is the first study to provide a detailed description of ultrasonographic imaging and measurement of the equine diaphragm. The novel technique developed to position the ultrasound transducer in a standardized location allowed examination and measurement of the diaphragm with good repeatability.