A comparison of 3-T magnetic resonance imaging and computed tomography arthrography to identify structural cartilage defects of the fetlock joint in the horse.
Authors: Hontoir Fanny, Nisolle Jean-François, Meurisse Hubert, Simon Vincent, Tallier Max, Vanderstricht Renaud, Antoine Nadine, Piret Joëlle, Clegg Peter, Vandeweerd Jean-Michel
Journal: Veterinary journal (London, England : 1997)
Summary
# Editorial Summary Cartilage lesions in the fetlock joint are clinically significant yet challenging to diagnose accurately, making the choice between imaging modalities critical for practitioners managing joint disease. This cadaveric study compared 3-Tesla MRI and computed tomography arthrography (CTA) head-to-head using 40 distal limbs, with gross pathology as the gold standard, employing DESS and SPACE sequences for MRI and contrast-enhanced CTA. CTA demonstrated substantially superior sensitivity (0.82 vs 0.41) for detecting cartilage defects, though both techniques achieved high specificity (0.96 and 0.93 respectively), with MRI's low positive predictive value (0.57) suggesting clinicians will encounter false positives that warrant caution in clinical interpretation. Whilst CTA's advantages include rapid acquisition and high accuracy for cartilage assessment, MRI retains diagnostic value for evaluating concurrent soft tissue and subchondral bone pathology—meaning the optimal imaging choice depends on clinical question and available resources rather than one modality superseding the other. Practitioners should recognise that MRI's reduced cartilage sensitivity may lead to underestimation of lesion severity, particularly relevant in performance horses where subtle defects might impact prognosis and return-to-work planning.
Read the full abstract on PubMed
Practical Takeaways
- •For definitive cartilage assessment in fetlock joints, CTA should be preferred over 3-T MRI due to superior sensitivity and specificity, though MRI remains valuable for evaluating concurrent soft tissue damage
- •Clinicians should be aware that negative MRI findings do not reliably exclude cartilage defects; CTA confirmation may be warranted when cartilage pathology is suspected
- •The choice between imaging modalities should consider clinical context: CTA for cartilage-focused diagnosis, MRI for comprehensive joint evaluation including soft tissues and bone changes
Key Findings
- •CTA demonstrated significantly higher sensitivity (0.82) and specificity (0.96) compared to 3-T MRI (0.41 and 0.93) for detecting cartilage defects in equine fetlock joints
- •MRI showed low positive predictive value (0.57) for cartilage defect identification despite good specificity
- •CTA had superior intra-rater (0.96) and inter-rater (0.92) agreement compared to MRI (0.82 and 0.88)
- •MRI provides additional diagnostic value for soft tissue and subchondral bone assessment despite reduced accuracy for cartilage lesions