Evaluation of the diagnostic accuracy of skeletal scintigraphy in lame and poorly performing sports horses.

This research objectively assesses the accuracy of skeletal scintigraphy, an imaging test, in diagnosing lameness or impaired performance in sports horses. It was found that, used alone or without discrimination, scintigraphy may not correctly identify the cause.

Overview of the Research

• The study is retrospective and analytical, utilizing cross-sectional data consisting of sports horses that had undergone scintigraphy examinations between March 2008 and December 2014.
• Only cases where a definite diagnosis was reached were considered, and all evaluations were carried out blindly, in order to minimize any bias.
• Areas that showed increased radiopharmaceutical uptake were identified and divided into two groups: ‘possibly relevant’ and ‘non-relevant’. This stratification helped in assessing the diagnostic validity of the skeletal scintigraphy.

Testing and Results

• Kappa statistics were used to measure the agreement between the scintigraphy results and the final diagnosis. If there was a complete match between the two, that would suggest high diagnostic accuracy of scintigraphy.
• Out of 1222 positive clinical diagnoses in 480 horses, only 43.8% of final diagnoses showed relevant increased radiopharmaceutical uptake during scintigraphy, indicating low sensitivity of this method. However, its specificity (accuracy to rule out a disease when the test is negative) was high at 94.0%.
• The overall agreement measured by kappa statistics was only fair, and it only became moderate when the test was improved by categorization.
• The test results showed substantial agreement with the final diagnosis only for issues located in the feet and the proximal aspect of the forelimb.

Conclusions

• The study revealed that the accuracy of skeletal scintigraphy for diagnostic purposes in sports horses is not very reliable when used as an isolated or indiscriminate screening tool.
• Despite high specificity, the low sensitivity of this method implies that it may fail to identify a significant proportion of actual problems. Its indiscriminate use could thus lead to misdiagnosis and incorrect treatment.
• The results suggest that more accurate or complementary diagnostic methods may need to be combined with skeletal scintigraphy to enhance its reliability in diagnosing lameness or poor performance in sports horses.