Accuracy of radiography in diagnosing medial coronoid disease (MCD) in dogs.

Ingrid Gielen, Bernadette Van Ryssen, Henri van Bree.

Department of Medical Imaging & Small Animal Orthopaedics,Veterinary Faculty, Ghent University, Belgium.

Key words: medial coronoid disease, elbow dysplasia, elbow disease.

Introduction.

The radiographic signs used to diagnose MCD includeperiarticularosteophyte formation (DJD). Other common radiographic signs of MCD are blurring of the cranial edge, abnormal shape of the medial coronoid process (MCP) and subtrochlear sclerosis (1, 2).Unfortunately, radiographic findings are not specific for MCD and are often inconclusive for a diagnosis.

Aim.

To investigatethe sensitivity and specificity of theradiographic detection of MCD compared to CT and using arthroscopy as a gold standard.Radiographic criteria used were DJD,shape of the MCP and subtrochlear sclerosis.

Material an Methods.

Retrospectively,radiographs of 150 elbows were examined for evidence of osteophyte formation. These 150 elbows were arthroscopically examined for evidence of MCD and all lesions were listed. Sensitivity and specificity were determined using the arthroscopic findings as gold standard.

Another radiographs of 180 elbows were examined for evidence of MCD using changes in outline, shape, radiodensity of the MCP, fragment and increased trochlear notch sclerosis.Then CT and arthroscopy were performed. Afterwards the CT- and arthroscopic findings were statistically compared. Sensitivity and specificity of the radiographic findings were then determined.

Results.

The sensitivity and specificity of the radiographic presence of DJD was 82% and 20,5% using arthroscopy as gold standard.

The correlation between the CT- and arthroscopic findings was 99.2 % meaning that the CT findings could be used as gold standard.

The sensitivity and specificity of the radiographic evaluation of the MCP delineation and trochlear sclerosis was 97.9 % and 64 % using the CT findings as gold standard.

Discussion.

The low specificityand only moderate sensitivity of radiographic signs of DJD in diagnosing MCD makes this an unreliable radiographic sign.

The high sensitivity of radiographic signs of MCP delineation and trochlear sclerosis in diagnosing MCD was comparable with a previous study (3) although false positive results still present a problem.

References.

  1. Diagnostic Imaging of Canine Elbow Dysplasia: A Review. C. Cook & J. Cook. Veterinary Surgery 2009, 38:144–153.
  2. Reliability of radiological assessment of ulnar trochlear notch sclerosis in dysplastic canine elbows. N. Burton, et al. Journal of Small Animal Practice 2008, 49: 572–576.
  3. Observer variability and sensitivity of radiographic diagnosis of canine medial coronoid disease. F. Rau, et al. TierärztlPrax 2011, 39: 313–322.