Hidden tarsal lesions: The role of flexed and oblique radiographs in young horses

Radiographically apparent tarsal lesions associated with developmental orthopedic disease and joint sepsis are common in young horses. Standard radiographic projections are routinely used to identify osseous changes but may fail to detect lesions due to superimposition and complex anatomy. This retrospective case series describes plantar trochlear ridge lesions in young horses that were not identified on standard four projection radiograph series but were detected using flexed lateromedial and flexed oblique projections. Cases were selected based on persistent clinical signs localizing to the tarsocrural joint despite non-diagnostic standard imaging. In all cases, flexed projections improved visualization and enabled identification and localization of lesions not apparent on conventional views. Flexed radiographic projections provide a practical adjunct to standard imaging in selected cases and specifically in improving detection of occult tarsocrural lesions.