Osteochondrosis of the femur

Osteochondrosis is a developmental disorder affecting cellular differentiation of physeal cartilage cells in dogs.(9,13-15,18,19) Common sites of occurrence include the humeral head in the shoulder joint and the medial aspect of the humeral condyle in the elbow joint. Lesions can occur less frequently on the trochlear ridges of the talus in the tibiotarsal joint and on the femoral condyles in the stifle joint. In a retrospective review by the author of 52 cases diagnosed radiographically or surgically as osteochondrosis from November 1991 through July 1996 at a rural university teaching hospital (Washington State University, Pullman, WA) and an urban general and referral hospital (Rowley Memorial Animal Hospital, Springfield, MA), only four (8%) patients with osteochondrosis had stifle joint lesions. Initially identified in 1959, osteochondrosis of the stifle joint has been sporadically described in clinical reports from Europe, Australia, and the United States during the 1970s and 1980s.(1,4,8,12) The largest case numbers of patients (103) were described in a 9-year review and a longterm (> 1 year) follow-up of affected dogs in Austria.(3) Osteochondrosis of the coxofemoral joint involving the head of the femur is extremely rare.(7,10) In this article, osteochondrosis of the femur will be discussed with regard to cause(s), diagnosis, and treatment.