Abstract
Front fetlock joint angle (FA) measurement might predict musculoskeletal injury. This study aimed to identify an accurate reliable tool, and develop a consistent method for measuring the FA. Fetlock centre of rotation was identified radiographically. Goniometer measurements were validated on ten vertically fixed post-mortem distal forelimbs by positioning the centre of rotation of the goniometer on the approximate centre of rotation of the joint for five measurements of each FA at three day intervals and one measurement by another person (rater B). Both FA’s of fourteen sound horses standing squarely on a concrete floor were repeated before and after lifting the contralateral limb, which was flexed at the carpus and held at the same level as the carpus of the standing limb. Consistency of measurements was assessed using both fetlock joints of five horses standing squarely on a concrete floor measured six times in random order and then with the contralateral limb lifted using both front fetlocks of eight horses measured five times in random order. The repeatability coefficient was calculated with WinPepi v10.5 software. The centre of rotation was on or around the eminence of the lateral collateral ligament. The repeatability coefficient of the goniometer validation was 4.7°. The mean FA for rater A and B were not significantly different (161.4° versus 162.9°). FA’s were significantly less after lifting the contralateral limbs (P<0.0001). FA’s before and after the contralateral limb was lifted were 150.1°±1.38 (range 140° to 160°) and 141.2°±1.79 (range 130° to 155°) in the right limb, and 154.9°±1.98 (range 139° to 167°) and 145.6°±2.17 (range 130° to 161°) in the left limb respectively. Repeatability coefficients were right 5.5, 5.2; left 4.8, 4.8 for square and limb-lifted respectively. The goniometer was a reliable tool to measure the FA, showing good repeatability either standing square or with a limb-lifted. arabic 6 English 45