Low-field magnetic resonance imaging of the equine tarsus: normal anatomy.

This article presents a study aimed at defining the healthy appearance of a horse’s tarsus (ankle joint) using low-field strength magnetic resonance imaging (MRI). Images were acquired using different planes and techniques, which were then compared to specimens for accuracy. MRI was found to provide a comprehensive evaluation of the anatomical relationships of the structures within the tarsus.

Objective

• The study was designed with the intention of identifying the normal anatomy of the adult equine tarsus with the use of low-field magnetic resonance images. This involves using a 0.064 Tesla scanner to get images in the sagittal (from the side), transverse (front view), and dorsal (top-down) planes. This helps in getting a comprehensive idea of the standard anatomy of a horse’s ankle joint.

Method

• The researchers used six cadavers, which means dead bodies of adult horses whose ankles were radiographically normal. Radiographically normal implies that nothing unusual was observed in the radiographs (X-rays) of these ankles.
• Echo sequences, these are particular timings for obtaining images in MRI, were used to ensure valid and useful images were acquired. T1-weighted images give information about the anatomy and T2-weighted images provide insights into the pathology or diseases present.
• The images obtained were then compared with cryosections, which are the cross-section or longitudinally cut sections of the imaged limbs frozen and studied under a microscope. This helped validate the MR images with actual anatomical structures.

Results

• As a result of these comparisons and observations, the best possible image planes were identified for various tissue structures present in the horse’s ankle joint. These include articular cartilage, subchondral bone, flexor and extensor tendons, tarsal ligaments, and synovial structures. This information is critical for clinicians seeking to diagnose or treat conditions related to these structures.
• The study clearly demonstrates that MR images provide a thorough evaluation of the anatomical relationships within the structures of the equine tarsus. It can serve as a solid basis for further studies and clinical applications related to the equine tarsus.