Relationship between repository radiographic findings and subsequent performance of Quarter Horses competing in cutting events.

OBJECTIVE To investigate potential associations between repository radiographic findings and subsequent performance of Quarter Horses competing in cutting events. DESIGN Retrospective cohort study. SAMPLE Repository radiographs (ie, radiographs obtained at the time of sale) for 343 client-owned horses. PROCEDURES Repository radiographic findings were compared with objective measures of performance, including the likelihood of competing; the likelihood of earning money as a 3-year-old, as a 4-year-old, and as a 3- and 4-year-old combined; and the amount of money earned as a 3-year-old, as a 4-year-old, and as a 3- and 4-year-old combined. RESULTS The presence of mild osteophytes involving the distal aspect of the tarsal joint was significantly associated with lower mean earnings as a 4-year-old. The presence of osteophytes on the dorsoproximal aspect of the middle phalanx of the hind limbs was significantly associated with an increased odds of earning money as a 4-year-old. Radiographic lesions of the medial femoral condyle of the stifle joint were not significantly associated with subsequent performance. CONCLUSIONS AND CLINICAL RELEVANCE Most abnormalities identified on repository radiographs were not significantly associated with subsequent performance. The significant association between mild tarsal osteophytosis and earnings was unexpected. Results of the present study indicated the need for further investigation of the relationship between radiographic findings and performance outcome in Western performance horses.

Contrast-enhanced CT for localizing compressive thoracolumbar intervertebral disc extrusion.

Thoracolumbar intervertebral disc extrusion is a common disease in dogs. Surgical decompression of the spinal cord is the preferred treatment. Localization of the compressive material is critical for surgical planning. Myelography has been used for localizing extruded disc material, but this procedure carries risk of complications. Computed tomography (CT) is becoming more available for use in veterinary medicine and CT myelography is used for localization of extruded disc material. This report compares CT with intravenous contrast medium and CT myelography for identifying extruded intervertebral discs. CT with intravenous contrast medium is as effective as CT myelography for determining level and laterality of compressive disc extrusions.

Imaging diagnosis--magnetic resonance imaging findings of primary cerebral hemangioma.

Intracranial hemangioma is a rare intraaxial hemorrhagic neoplasm with imaging characteristics similar to other intracranial hemorrhagic lesions. We describe two canine cerebral hemangiomas that appeared as poorly circumscribed intraaxial compressive lesions that were predominantly hypointense on T2 sequences and heterogeneously contrast enhancing. Both lesions had perilesional edema and were hypointense on T2(*) -gradient recalled echo sequences, consistent with hemorrhage. In one tumor a short partial peripheral rim was present, which was suggestive of hemosiderin deposition. Cerebral hemangioma should be included as a differential for hemorrhagic intracranial lesions.

Computed tomographic appearance of primary lung tumors in dogs.

Canine primary lung tumors typically appear radiographically as a well-circumscribed solitary mass in the periphery of a caudal lung lobe. Consolidated and diffuse forms of primary lung tumors have also been described. Nineteen dogs with computed tomographic (CT) images of the thorax and a histological diagnosis of primary lung tumor (17 primary carcinomas and two primary sarcomas) were evaluated retrospectively to characterize the CT findings. All primary lung tumors were bronchocentric in origin with internal air bronchograms. The bronchi were typically narrowed, displaced, and often obstructed by the tumor. Eighteen of 19 (95%) of the tumors were solitary and there was one pneumonic/alveolar form. Most solitary tumors were well circumscribed (17/18), located in the central to periphery of the lung (14/18), and in a cranial or caudal lobe (16/19). Most primary lung tumors (11/17) had mild to moderate heterogeneous contrast enhancement. Five of 19 dogs (26%) had evidence of pulmonary metastasis. Internal mineralization (3/19) and tracheobronchial lymphadenopathy (4/19) were also identified. On CT examination, solitary, well circumscribed, bronchocentric masses with internal air bronchograms are consistent with a primary pulmonary tumor in dogs.

Metacarpophalangeal and metatarsophalangeal osteoarthritis in 49 dogs.

Although osteoarthritis (OA) is a common and debilitating condition in the canine patient, few data are available on OA of the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joints. Review of medical records of 49 dogs with a radiographic diagnosis of MCP or MTP OA presented over a 7-year period demonstrated that OA was an "incidental finding" for the majority of animals (n=35), while 14 dogs were identified as clinically lame as a result of MCP or MTP OA. Dogs that were clinically lame as a result of MCP or MTP OA were significantly more likely to have visible swelling over the affected digits. Five times as many dogs were diagnosed with MCP OA than with MTP OA, and the majority of dogs had radiographic changes on multiple digits. Review and scoring of radiographs (n=44 dogs) for six radiographic signs of OA followed by logistic regression analysis demonstrated that the two lateral digits of the front limb were significantly more likely to have osteophytosis and enthesophytosis than the two medial digits. Osteoarthritis of MCP and MTP joints has unique radiographic features that are not seen in the stifle, hip, shoulder, or elbow; these features can complicate accurate diagnosis, particularly differentiation from primary bone neoplasia. These data underscore the clinical relevance of this condition and provide useful information detailing which and how many digits are most commonly affected, potentially assisting discrimination between OA and neoplasia.

Comparison of mean bone densities of three preparations of the distal portion of the equine third metacarpal bone measured by use of quantitative computed tomography.

OBJECTIVE: To evaluate whether cutting equine subchondral bone to demarcate specific regions of interest (ROIs) influences the mean density for that bone as measured via quantitative computed tomography (QCT). Sample population-2 metacarpophalangeal joints from equine cadavers. PROCEDURES: The distal portion of the third metacarpal bone of each intact metacarpophalangeal joint was scanned via CT to simulate in vivo conditions. Each joint was subsequently disarticulated and dissected, and the distal portion of the dissected third metacarpal bone in air was scanned. Then, six 1-cm(2) areas representing ROIs were cut into the distal condylar surfaces to depths of approximately 1 cm, and the bone was scanned again. Three-dimensional CT models of the 3 bone preparations were generated for each third metacarpal bone on the basis of data from each set of scan images, and densities of the 6 ROIs were measured. Mean bone densities for the 6 ROIs were compared among models of intact, dissected, and cut third metacarpal bone scans. RESULTS: Mean bone density was significantly lower in cut bone preparations, compared with that in intact or dissected bone. Differences between mean bone densities for intact and dissected bone preparations were not significant. CONCLUSIONS AND CLINICAL RELEVANCE: Cutting subchondral bone to demarcate specific ROIs prior to CT imaging significantly lowered mean bone density as measured via QCT and thus introduced substantial artifacts. These findings have direct implications on techniques for CT modeling of equine subchondral bone in the characterization of joint diseases in horses.

Comparison of radiographic and anatomic femoral varus angle measurements in normal dogs.

OBJECTIVE: To determine if the clinically practiced method of radiographic femoral varus angle (R-FVA) measurement is repeatable, reproducible, and accurate. STUDY DESIGN: Radiographic and anatomic study. ANIMALS/SAMPLE POPULATION: Normal Walker hound cadavers (n=5) and femora (n=10). METHODS: Cadavers were held in dorsally-recumbent and torso-elevated positions as 3 craniocaudal radiographs were made of each femur, by each of 2 different technicians. Femora were then harvested for direct measurement of anatomic femoral varus angle (A-FVA). R-FVA was measured on each radiograph by each of 3 examiners on 3 separate occasions. Intra-observer (repeatability) and inter-observer (reproducibility) variance in R-FVA measurement and the strength of relationship between R-FVA and A-FVA (accuracy) were determined. RESULTS: Mean (+/-SD) A-FVA was 5.2+/-2.1 degrees (range, 2.4-8.2 degrees). Mean (+/-SD) R-FVA was 5.8+/-1.0 degrees (range, 2.7-9.6 degrees). Intra-observer variance (range: 11-16%) and inter-observer variance (16%) were acceptable. The strength of relationship between measured R-FVA and A-FVA (maximum adjusted R(2)<0) was unacceptably low regardless of observer, patient position, or radiographic technician. CONCLUSION: R-FVA measurement was repeatable and reproducible, but not statistically accurate in predicting A-FVA in these 5 normal Walker hounds. The detected inaccuracy may be real or the result of a selection bias for normal dogs obscuring the true relationship. CLINICAL RELEVANCE: R-FVA may not be an accurate method of femoral varus measurement in dogs with A-FVA<10 degrees. Using Slocum's criteria for distal femoral osteotomy (R-FVA>10 degrees), the procedure would not have been erroneously performed in any of the normal dogs of this study.

Comparison of surgical treatment options for cranial cruciate ligament disease in large-breed dogs with excessive tibial plateau angle.

OBJECTIVE: To identify surgical techniques performed by veterinary surgeons for the treatment of cranial cruciate ligament disease in large-breed dogs with excessive tibial plateau angle (eTPA), compare their outcomes, identify risk factors for postoperative complications, and compare outcome and complication rate with tibial plateau leveling osteotomy (TPLO) in dogs without eTPA. STUDY DESIGN: Multicenter, case-control study. ANIMALS: eTPA group (TPA>or=35 degrees)=58 dogs (78 stifles); control group (TPA14 degrees. Loss of tibial plateau leveling during convalescence was the most commonly observed major complication; addition of ancillary implants to TPLO significantly reduced its incidence. Postoperative complications were more common in dogs with eTPA than in dogs without eTPA; however, no difference in owner-perceived outcome was identified. CONCLUSIONS: Surgical treatment of dogs with eTPA has a higher complication rate, but comparable outcome to that of dogs without eTPA. CLINICAL RELEVANCE: Postoperative TPA

Risk factors for excessive tibial plateau angle in large-breed dogs with cranial cruciate ligament disease.

OBJECTIVE: To identify risk factors for development of excessive tibial plateau angle (TPA) in large-breed dogs with cranial cruciate ligament disease (CCLD). DESIGN: Case-control study. ANIMALS: 58 dogs with excessive TPAs (ie, TPA >or= 35 degrees ; case dogs) and 58 dogs with normal TPAs (ie, TPA or= 35 degrees in both limbs were 13.6 times (95% confidence interval, 2.72 to 68.1) as likely to have been neutered before 6 months of age as were control dogs with TPA

Comparison of gross and histopathologic findings with quantitative computed tomographic bone density in the distal third metacarpal bone of racehorses.

Comparison of subchondral bone density determined by quantitative computed tomography (CT) with gross and histopathologic changes have not been made in horses. The goal of this study was to determine if mean quantitative CT density and mean voxel standard deviation are associated with the presence and severity of osteochondral lesions in the palmar aspect of the distal third metacarpal bone in racing horses. Metacarpophalangeal joints from nine racehorses were imaged using CT and scored for gross damage. Four-millimeter-thick sagittal and 30 degrees palmar dorsal plane sections were cut, decalcified and stained with hematoxylin and eosin from the distal third metacarpal bone. Microscopic osteochondral lesions and subchondral remodeling were scored on a scale of 0-3. Percent subchondral bone, expressed as the ratio of bone volume to tissue volume, was also measured. Mean quantitative CT density and mean voxel standard deviation were measured from three-dimensional models of CT images comparable with histologic sections. Mean quantitative CT density was not associated with lesion severity or number of lesions. A weak correlation between mean quantitative CT density and gross score was found, but mean quantitative CT density was not predictive for gross score. Mean voxel standard deviation was not correlated with gross or histopathologic measures, but was predictive of mild osteochondral lesions. Results support the association of subchondral remodeling with the development of palmar metacarpal lesions. However, there was not a strong correlation between mean quantitative CT density or mean voxel standard deviation and histopathologic lesions of the distal third metacarpal bone.

Evaluation of avocado and soybean unsaponifiable extracts for treatment of horses with experimentally induced osteoarthritis.

OBJECTIVE: To evaluate the use of a combination of avocado and soybean unsaponifiable (ASU) extracts for the treatment of experimentally induced osteoarthritis in horses. ANIMALS: 16 horses. PROCEDURES: Osteoarthritis was induced via osteochondral fragmentation in 1 middle carpal joint of each horse; the other joint underwent a sham operation. Horses were randomly allocated to receive oral treatment with ASU extracts (1:2 [avocado-to-soybean] ratio mixed in 6 mL of molasses; n = 8) or molasses (6 mL) alone (placebo treatment; 8) once daily from days 0 to 70. Lameness, response to joint flexion, synovial effusion, gross and histologic joint assessments, and serum and synovial fluid biochemical data were compared between treatment groups to identify effects of treatment. RESULTS: Osteochondral fragmentation induced significant increases in various variables indicative of joint pain and disease. Treatment with ASU extracts did not have an effect on signs of pain or lameness; however, there was a significant reduction in severity of articular cartilage erosion and synovial hemorrhage (assessed grossly) and significant increase in articular cartilage glycosaminoglycan synthesis, compared with placebo-treated horses. CONCLUSIONS AND CLINICAL RELEVANCE: Although treatment with ASU extracts did not decrease clinical signs of pain in horses with experimentally induced osteoarthritis, there did appear to be a disease-modifying effect of treatment, compared with findings in placebo-treated horses. These objective data support the use of ASU extracts as a disease-modifying treatment for management of osteoarthritis in horses.

Clinical, biochemical, and histologic effects of intra-articular administration of autologous conditioned serum in horses with experimentally induced osteoarthritis.

OBJECTIVE: To assess the clinical, biochemical, and histologic effects of intra-articular administration of autologous conditioned serum (ACS) in the treatment of experimentally induced osteoarthritis in horses. ANIMALS: 16 horses. PROCEDURES: Osteoarthritis was induced arthroscopically in 1 middle carpal joint of all horses. In 8 placebo- and 8 ACS-treated horses, 6 mL of PBS solution or 6 mL of ACS was injected into the osteoarthritis-affected joint on days 14, 21, 28, and 35, respectively; PBS solution was administered in the other sham-operated joints. Evaluations included clinical assessment of lameness and synovial fluid analysis (performed biweekly); gross pathologic and histologic examinations of cartilage and synovial membrane samples were performed at necropsy. RESULTS: No adverse treatment-related events were detected. Horses that were treated with ACS had significant clinical improvement in lameness, unlike the placebo-treated horses. Among the osteoarthritis-affected joints, ACS treatment significantly decreased synovial membrane hyperplasia, compared with placebo-treated joints; although not significant, the ACS-treated joints also appeared to have less gross cartilage fibrillation and synovial membrane hemorrhage. The synovial fluid concentration of interleukin-1 receptor antagonist (assessed by use of mouse anti-interleukin-1 receptor antagonist antibody) was increased following treatment with ACS. CONCLUSIONS AND CLINICAL RELEVANCE: Results of this controlled study indicated that there was significant clinical and histologic improvement in osteoarthritis-affected joints of horses following treatment with ACS, compared with placebo treatment. On the basis of these findings, further controlled clinical trials to assess this treatment are warranted, and investigation of the mechanisms of action of ACS should be pursued concurrently.

Evaluation of canine gastric motility with ultrasonography.

For the evaluation of canine gastric motility with ultrasonography, contraction number of pyloric antrum and gastric emptying time (GET) by area and volume method developed by Bolondi et al.'s method were studied in 14 dogs. All experimental dogs were administered with saline and soup solution (10 ml/kg, B.W.). The mean values of contraction number of pyloric antrum in saline and soup group were 4.19 +/- 1.30/min and 4.82 +/- 0.65/min before feeding, and overall mean values were 4.66 +/- 1.37/min and 5.13 +/- 1.71/min, respectively. The mean values of the GET by area and volume method were 36.73 +/- 11.27, 40.00 +/- 8.87 min in saline group and 61.35 +/- 17.58, 59.11 +/- 14.46 min in soup group. In the GET in saline and soup groups, there was no significant difference between the area and volume method (p>0.05). Therefore, Bolondi et al.'s method by ultrasound can be used to evaluate the antropyloric motility and gastric emptying time with area and volume methods. The area method is easier to determine the GET than the volume method, but the latter is more accurate.