Clinical history A 7 year old male Rottweiler presented for evaluation of recurrent hindlimb lameness - He had been previously diagnosed as having chronic arthrosis secondary to hip dysplasia VD radiographs were made of the pelvis Lateral radiographs were also made of the elbows because of suspected minimal pain in the forelimbs detected on physical examination.What is your diagnosis? VD pelvis with limbs extended - left femur rotated externally causing lateral positioning of the patella Radiographic changes - pelvis The study is well positioned and the hip joints can be closely evaluated.
- Malformed femoral heads with thickened femoral necks bilaterally
- Minimal subluxation of both femoral heads
- Early bony filling of the acetabular cups
- Increased density of the subchondral bone in the acetabulae bilaterally
- Patchy sclerosis within the trochanteric regions bilaterally
Elbows lateral view - 90 degrees Radiographic changes - elbows Bony changes are noted more prominent on the right elbow on comparison of the two joints.
- New bone formation on the anconeal process (arrow)
- New bone formation around the trochlear notch (arrow)
- New bone formation (spurring) distal humeral articular surface (arrow)
- Indistinct appearance of the medial coronoid process (arrow)
Changes on the left elbow are less prominent Radiographic diagnosis Prominent reactive bony changes plus subluxation indicative of bilateral chronic arthrosis in both hip joints secondary to hip dysplasia Moderate reactive bony changes plus an indistinct mcp on the right indicative of chronic arthrosis secondary to elbow dysplasia - changes on the left are less prominent but are also diagnostic of elbow dysplasia Is the arthrosis the cause of the current clinical signs ?? Look at the studies a second time. Then, look at the figures shown next that are enlarged. Enlargements Radiographic changes
- A mixed pattern of bony destruction and production occupies most of the left ilial wing - the lesion is slightly expansive
- A thin border of reactive periosteal new bony surrounds the lesion
- The zone of transition is difficult to identify but appears long -
Radiographic diagnosis
- The pattern of bony destruction/production in the expansive lesion and the indistinct periosteal new bone plus the absence of a sharply defined zone of transition are suggestive of a malignant lesion - both primary and metastatic tumors are considered - cortical destruction is difficult to evaluate on a pelvic lesion and not often helpful in diagnosis
- The differential diagnosis must include an osteomyelitis with a bone biopsy necessary for diagnosis
- How do you exclude overlying fecal material causing the ilial changes ??
Diagnosis The findings on examination of the biopsy were those of a malignant lesion without definite determination of the cell type.The dog was euthanized because of the elbow and hip arthrosis, the malignant tumor, and the older age of the patient.
