Radiographic measurement of canine stifle joint angles using four different landmark methods

Abstract

This study was conducted to compare angles physically set on the stifle joints of cadaveric limbs of dogs with the results by four different radiographic methods for stifle angle measurement. Thirteen pelvic limbs from various large breeds and skeletally-mature dogs were used. The stifles were fixed at four angles: 125°, 130°, 135° and 140°. Altogether 52 radiographs were done. Each stifle angle set on the cadaver limbs was radiographically measured using four sets of landmarks (the goniometric, long axis, eminence and kinematic methods). We found similarity between angles physically set on cadaver limbs and radiographically measured using the long axis method (P > 0.05). The goniometric method showed similarity in group of limbs with the stifle fixed at 140° (P > 0.05), and other measurements differed significantly (P < 0.05). Eminence and kinematic method measurements were different compared to the angle of fixation of the stifle on the cadaver (P < 0.05) but similar compared to each other (P > 0.05). The method of stifle joint angle measurement should be considered when comparing similar studies, and also in pre-operative measurements for some tibial osteotomies aimed at stabilizing the joint after cranial cruciate ligament rupture.