ULTRASONOGRAPHY OF THE EQUINE TARSUS

Ultrasonography was used to delineate the sonographic anatomy of the equine tarsus with emphasis on the flexor tendons and plantar ligament at the plantar surface of the tarsus, the medial collateral ligaments and the dorsomedial joint capsule of the tibiotarsal joint. The cross-sectional gross anatomy of these tendons and ligaments was evaluated in 6 cadaver limbs. Using a 5.5 MHz mechanical sector scanner, the examined tendons and ligaments were easily identified as hyperechoic structures in 10 limbs of normal live horses. The normal ultrasonographic appearance of the dorsomedial tibiotarsal joint capsule was studied in 8 cadaver limbs. The inner surface of the tibiotarsal joint capsule was covered with villi; short and pointed in the mid region, resembling a small nodular mass proximally and a straggly beard distally. In 4 lame horses diagnostic ultrasound aided the diagnosis of plantar swellings, medial collateral joint ligamentous injury and hypertrophic synovitis.