Radiographic anatomy of soft tissue attachments in the equine metacarpophalangeal and proximal phalangeal region.

The sites of bony attachment of the tendons, ligaments, and fibrous portion of the joint capsules of the equine metacarpophalangeal (fetlock) joint region were determined by gross dissection. These sites were transposed to standard radiographic views of the fetlock joint to yield illustrations that can be used as an aid in the diagnosis of soft tissue pathology from radiographs. Evidence of direct attachment of the common digital extensor tendon to the proximal phalanx was not found. Branches of the superficial digital flexor tendon were found to insert only on the middle phalanx. The recently described sites of insertion of the branches of the superficial digital flexor tendon to the proximal phalanx were found to be sites for attachment of the deep axial palmar ligaments of the proximal interphalangeal joint.