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

This research paper discusses the anatomical structure of the hoof area in horses, indicating where tendons, ligaments, and joint capsules attach to bone, in order to assist in diagnosing soft tissue damage from radiographs. No attachment of the common digital extensor tendon to the proximal phalanx was found, and branches of the superficial digital flexor tendon were found to insert only on the middle phalanx of a horse’s leg.

Objective of The Research

• This study aims to determine the exact areas of bone attachment of tendons, ligaments, and the fibrous portion of joint capsules specifically in the metacarpophalangeal or fetlock joint region in horses. This was done through comprehensive dissection.
• The identified sites were then mapped onto standard radiographic views of the fetlock joint leading to the formation of diagrams. Hence, said diagrams could be used to diagnose soft tissue pathologies from radiographs.

Key Findings

• The research revealed that the common digital extensor tendon, a tendon important for limb extension, does not attach directly to the proximal phalanx, one bone in the equine hoof.
• Insertions of branches of the superficial digital flexor tendon, contributing to flexion of the limb, were observed only on the middle phalanx, another bone situated in the hoof.
• The study also confirmed that previously known insertion sites for branches of the superficial digital flexor tendon on the proximal phalanx were in fact sites of attachment for deep axial palmar ligaments of the proximal interphalangeal joint.

Implication of the Research

• This research offers essential insight into the detailed anatomy of the equine metacarpophalangeal and proximal phalangeal region, which can aid in understanding pathologies related to these parts.
• The detailed mapping achieved through this study can facilitate more precise diagnoses of soft tissue injuries or abnormalities in the equine fetlock joint region using radiographs.
• The absence of attachment of a key tendon to a particular bone, as well as the clarification on the true attachment site of the deep axial palmar ligaments, contribute to the overall understanding of the equine limb function and potential areas prone to injury.