Correlation of Articular Cartilage Thickness Measurements Made with Magnetic Resonance Imaging, Magnetic Resonance Arthrography, and Computed Tomographic Arthrography with Gross Articular Cartilage Thickness in the Equine Metacarpophalangeal Joint.

The study researched the effectiveness of different imaging methods in estimating the thickness of cartilage in horses’ metacarpophalangeal joints. Despite various approaches, no single method provided consistently accurate measurements, making it difficult to identify cartilage injuries.

Research Overview

In the world of equine sports, osteoarthritis of the metacarpophalangeal joint is a frequent cause for lameness or performance issues in horses. One of the defining characteristics of this condition is the damage to the articular cartilage. The authors of the study explored different, non-invasive ways to measure the thickness of this cartilage — a key aspect in diagnosing potential injuries in time for effective treatment.

Methodology

The study involved the examination of fourteen cadaveric equine thoracic limbs. Any limbs that showed signs of issues, like pathology of the metacarpophalangeal articular cartilage, were excluded. The measurements of articular cartilage thickness were carried out in nine regions of the third metacarpal bone and proximal phalanx.

• The first imaging method used was MRI, more specifically, sagittal plane MRI sequences.
• Then, after intra-articular contrast administration, the limbs were imaged with sagittal plane MRA and sagittal CTA reformations.
• For the second set of seven limbs, to enhance resolution of the images and distinguishability of the cartilage, researchers injected a larger volume of contrast, up to the limit of distension for the joint.

Findings

Even after these elaborate measurements, the results did not conclusively identify one imaging test that performed better than the others in terms of correlating with gross cartilage thickness. It remains considerably troublesome to identify the cartilage surfaces specifically where the proximal phalanx and third metacarpal bone are in close contact. The study suggests that further research is needed to develop a more accurate, non-invasive method to measure the thickness of the articular cartilage.