Research Paper: Anatomy and Ultrasonographic Morphometric Measurements of Palmar Metacarpal Tendons and Ligaments in Pure Persian Arabian Horses

The evaluation of musculoskeletal system in horse veterinary medicine is very important because of its effect on equine performance. The current study provided an ultrasonography description of the palmar tendons and ligaments of the metacarpus in pure Persian Arabian horses. The metacarpal regions of 10 healthy mare pure Persian Arabian horses were prepared for ultrasonography in respect of 6 regions (1, 2, 3, 4, 5, 6). For a better description, the left and right forelimbs of an adult healthy donkey was anatomically studied, too. All the structures appeared with acceptable contrast and visibility at region 2. Echogenicity of Deep Digital Flexor Tendons (DDFT) from the 4th region was hyperechoic to isoechoic, compared to Superficial Digital Flexor Tendons (SDFT), and Suspensory Ligament (SL) of this level observed in the branching area was hyperechoic, in comparison to DDFT and SDFT; however, MSL and LSL were hypoechoic, compared to SDFT and DDFT. Additionally, the Inferior Check Ligament (ICL) and new discovered ligament (second superior check ligament) were detected in both anatomical and Ultrasonographical studies. There were no echogenicity differences between right and left forelimbs. Based on the obtained results, the Mean±SD maximum dorsopalmar thickness of SDFT, DDFT, AL and SL of the left forelimb were 6.3±0.2, 8.5±0.01, 5.3±0.01, and 6.7±0.3, respectively.  The obtained data are strongly compatible with the previous findings in horses regarding the echogenicity and shape of palmar tendons and ligaments. Generally, it is assumed that transverse images better illustrate the tendons and ligaments.