Obtaining more data on breed predisposition of dogs to the cranial cruciate ligament (CCL) rupture and data on accompanying abnormalities of joints of pelvic limbs affected by the CCL rupture may help in answering some questions concerning the etiology and pathogenesis of the disorder.In 183 patients affected by the CCL rupture out of the total of 11579 dogs, evaluated and/or treated in the Clinic of Surgery and Orthopedics at the Veterinary and Pharmaceutical University Brno from January 1997 till April 2000, the breed, weight, sex and concurrent joint abnormalities of pelvic limbs (hip dysplasia, patellar luxation and osteochondrosis of the stifle joint) were recorded.A total of 213 stifle joints (16.39% of cases were bilateral CCL ruptures) were affected. Increased breed predisposition (χ 2 -test; p < 0.01) was found in American Staffordshire Terrier, Rottweiler, Brazilian Fila, Labrador Retriever, American Cocker Spaniel, Chow Chow, German Shorthaired Pointer, Saint Bernard and Bullmastiff and also on the 5% level of significance in Boxer.Contrary to published data, the high incidence of CCL rupture was found in Brazilian Fila (13.43% of prevalence). The risk of the CCL rupture in German Shepherd Dog was significantly lower (χ 2 -test; p < 0.01) than in other breeds studied. At the same time in 27 patients with the CCL rupture we diagnosed canine hip dysplasia, in 9 dogs medial patellar luxation and in 5 cases osteochondrosis of the stifle joint. The data found are briefly discussed in relation to the possible CCL rupture etiology.
Stifle joint, cranial cruciate ligament injury, prevalence, etiopathogenesisCranial cruciate ligament (CCL) rupture belongs to the most frequent acquired diseases of the stifle joint not only in dogs and cats (Ryer 1981) but also in man (Griffin et al. 2000). Many questions concerning the etiopathogenesis of the CCL rupture remains unanswered. The integrity of the cranial cruciate ligament may be lost due to direct trauma of the stifle which may also result in damage of other structures of the stifle such as the caudal cruciate ligament, medial and lateral collateral ligaments, meniscus, joint capsule and eventually bone structures of the joint (femur, tibia and patella) (Bruce 1998). The number of cases of in such a way originated CCL ruptures is relatively small. With regard to the absence of direct trauma of the stifle joint in most cases of CCL rupture, various predisposing factors taking part in decreasing the firmness of the ligament, resulting in its inability to stand up to normal loading and subsequent rupture have been considered. Decreased CCL resistance to forces of pull has been proved in animals with aging. Results of concurrent histological examination have proved degenerative changes of the ligament that were more severe with advancing age of dogs and occurred earlier in dogs of large breeds (body weight > 15 kg) (Vasseur et al. 1985). There may also be other predisposing factors such as