Femoral Head Osteotomy in Horses and Cattle

Femoral head ostectomy was performed in six horses, three ponies, and four cattle for treatment of fractures of the femoral capital physis, coxofemoral luxation, fractured acetabulum, or severe degenerative joint disease. The procedures were performed via a cranial approach that did not involve osteotomy of the greater trochanter. A dorsal approach for femoral head ostectomy via osteotomy of the greater trochanter was evaluated in three healthy adult ponies. Three animals (2 ponies, 1 calf) were euthanatized within a month and one horse was euthanatized at year 2 due to postoperative complications. Nine animals were discharged to owners and six of them fulfilled their intended functions of breeding, milking, and being kept as companions. One horse was lost to follow-up and two horses died of causes unrelated to the surgery. All surviving animals had a residual lameness that was described by owners as mild to moderate. None of the horses were used as riding animals. The mean age and weight of 10 animals that regained weight-bearing locomotion was 3.1 months and 84 kg; for three unsuccessful cases it was 34 months and 174 kg. We concluded that femoral head ostectomy was a viable salvage procedure for large animals with capital femoral physeal fracture, chronic coxofemoral luxation, or acetabular fracture. Surgical prognosis appeared to be favorable in young cattle and fair in young horses or ponies weighing less than 100 kg. Osteotomy of the greater trochanter resulted in superior exposure of the intact coxofemoral joint and allowed easier, less traumatic surgical luxation of the joint to facilitate femoral head ostectomy.     

Cranial nerve hamartoma in a dog

An 11-year-old, male, neutered Cavalier King Charles spaniel was euthanatized because of recurrent seizures and inflammatory bowel disease. An incidental finding at necropsy was the presence of bilateral, firm, white nodules across the petrosal crest of the skull. Microscopically, the nodules were composed of normal myelinated nerve fibers within a mucinous stroma. A diagnosis of cranial nerve hamartoma was made.     

In Vitro Analysis of Two Canine Pelvic Osteotomy Techniques

The ability of two canine pelvic osteotomy techniques to provide lateral rotation of the acetabulum was compared in vitro using an instrumented spatial linkage to measure acetabular displacement. Technique 1 was a double osteotomy and technique 2 was a triple osteotomy. We demonstrated that technique 1 provided more lateral rotation of the acetabulum. Both techniques provided a large amount of acetabular an-teversion. No relationship could be found between pelvic morphometry and final acetabular position. We concluded that the surgeon is the primary factor controlling final acetabular position.     

Cranial vena cava aneurysm in a dog

A 1.5-year-old mixed breed dog was presented for evaluation of arrhythmia and a cranial mediastinal density was noted on thoracic radiographs. The density was determined to be a cranial vena cava aneurysm based on ultrasonographic and angiographic testing. No treatment was initiated and the dog remains asymptomatic for the cranial vena cava aneurysm at 6 years of age. Although rare, cranial vena cava aneurysm should be a differential diagnosis for dogs with cranial mediastinal abnormalities on thoracic radiographs.     

Cranial mediastinal carcinomas in nine dogs*

Nine dogs were diagnosed with cranial mediastinal carcinomas. Based on histological and immunohistochemical analysis, four dogs were diagnosed with ectopic follicular cell thyroid carcinomas, one dog with ectopic medullary cell thyroid carcinoma, two dogs with neuroendocrine carcinomas and two dogs with anaplastic carcinomas. Clinical signs and physical examination findings were associated with a space‐occupying mass, although one dog was diagnosed with functional hyperthyroidism. Surgical resection was attempted in eight dogs. The cranial mediastinal mass was invasive either into the heart or into the cranial vena cava in three dogs. Resection was complete in six dogs and unresectable in two dogs. All dogs survived surgery, but four dogs developed pulmonary thromboembolism and two dogs died of respiratory complications postoperatively. Adjunctive therapies included pre‐operative radiation therapy (n = 1) and postoperative chemotherapy (n = 3). Three dogs had metastasis at the time of diagnosis, but none developed metastasis following surgery. The overall median survival time was 243 days. Local invasion, pleural effusion and metastasis did not have a negative impact on survival time in this small case series.