ULTRASONOGRAPHY OF THE METACARPOPHALANGEAL JOINT OF POLO HORSES OF THE WEST OF THE STATE OF RIO DE JANEIRO: SCANING PROTOCOL AND MEASUREMENTS

Abstract

The evolution of technology has increased the sensitivity of diagnostic imaging, especially in ultrasonography. The transducers can provide greater frequency and therefore the image has better resolution. This makes it possible to analyze structures that weren’t detailed before, generating the need for constant updating of knowledge about their normal standard. This study aims to detail the ultrasound examination of the metacarpophalangeal joint of Polo horses and get reference values for the physiological pattern of soft tissue structures in the region. For this, were examined the forelimbs of 18 adult horses, male and female, weighing 350 to 480 kg and age of four to 12 years. The horses were all regular practitioners of Polo and had no complaint of lameness or other signs of injury to the locomotor system. Structures that are often studied as the superficial digital flexor tendon (SDFT) and deep digital flexor tendon (TFDP) were examined, as the structures of less attention in the literature as the joint capsule (CA), its dorsal fold (Vilo or Villus) and the collateral ligaments. The cross-sectional area were SDFT - 1.23 cm²; TFDP - 1.58 cm²; TEDC - 0.48 cm²; L SUS-RL - 1.16 cm²; SUS L-RM - 1.26 cm²; SES R L - 0.65 cm²; L SES OM - 0.29 cm²; SES L OL - 0.26 cm². In the longitudinal data we found the following: LAP 0, 40cm, CA - 0.84 cm; Vilo - 0.62 cm, L COL-M - 0.46 cm; LCOL-L - 0.44 cm; BFSD - 0.78 cm. Data were compared with those published in the literature, where similarities were found in studies with jumping horses. But there were found discrepancies as the difference in thickness of the villus. Another factor was related with structures pairs, that showed the medial branches always a little larger than the lateral branches. On based on this, we concluded that it is necessary to study the physiological pattern of joint structures of different types of equestrian activities and understand the differences between them. Only then can it be done a reliable ultrasound scan and as well as its clinical interpretation.