Computed tomography of the stifle region in the horse: a comparison with radiographic, ultrasonographic and arthroscopic evaluation

Abstract

Subject of this paper are the different diagnostic possibilities of computed tomography in the stifle joint region in horses. Results were obtained from 20 clinical cases with diseases of the stifle joint (Group A) and from 10 horses without any patholocical findings in this area (Group B). Horses belonging to Group A showed changes of the articular surface of the trochlea ossis femoris, the condyli ossis femoris and the proximal tibia as well as soft tissue changes of the ligg. cruciata, ligg. collateralia and the menisci. The computed tomographic examination was compared to radiographic (in all cases), ultrasonographic (in 18 cases) and arthroscopic results (in 17 cases). The advantage of computed tomography versus radiography is to locate isolated fragments, to accentuate bone remodelling and to improve the imaging of the fossa intercondylaris, the area intercondylaris caudalis and the incisura poplitea. Because of missing detail resolution as seen in ultrasonography and arthroscopy of the cranial parts, the computed tomographic evaluation is of special value to assess the soft tissue structures of the caudal parts. Horses belonging to Group B were examined via nativ- and negative-contrast computed tomography imediately after euthanasia (10 stifle joints). The average density of the medial meniscus in these horses was 113.9 HU (standard deviation 14.4 HU) and of the lateral meniscus 118.1 HU (standard deviation 10.4 HU). The insufflation of CO2 up to a pressure of 120 mmHg simplified the differentiation of intraarticular structures and made it possible to prove arteficial meniscal defects in 4 of 5 cases.