Supported by the Grayson Jockey Club Research Foundation Grant # 525698.
CHARACTERIZATION OF THE ORIGIN AND BODY OF THE NORMAL EQUINE REAR SUSPENSORY LIGAMENT USING ULTRASONOGRAPHY, MAGNETIC RESONANCE IMAGING, AND HISTOLOGY
Version of Record online: 14 FEB 2012
© 2012 Veterinary Radiology & Ultrasound
Veterinary Radiology & Ultrasound
Volume 53, Issue 3, pages 318–328, May/June 2012
How to Cite
Schramme, M., Josson, A. and Linder, K. (2012), CHARACTERIZATION OF THE ORIGIN AND BODY OF THE NORMAL EQUINE REAR SUSPENSORY LIGAMENT USING ULTRASONOGRAPHY, MAGNETIC RESONANCE IMAGING, AND HISTOLOGY. Veterinary Radiology & Ultrasound, 53: 318–328. doi: 10.1111/j.1740-8261.2011.01922.x
- Issue online: 16 MAY 2012
- Version of Record online: 14 FEB 2012
- Manuscript Accepted: 3 JAN 2012
- Manuscript Received: 3 JUN 2011
- Grayson Jockey Club Research Foundation. Grant Number: 525698
The suspensory ligament is difficult to image accurately, partly because it contains ligamentous fibers, as well as noncollagenous adipose and muscle tissue in the normal horse. Our hypothesis was that magnetic resonance (MR) imaging would be more accurate than ultrasonography in identifying the size of the suspensory ligament and the presence and size of noncollagenous tissues within the ligament. Eleven horses were used for ultrasonographic and MR imaging and histologic evaluation of the rear suspensory ligament. The origin and body of the normal suspensory ligament had a heterogenous appearance on MR images with two separate islands of mixed signal intensity evident throughout its otherwise hypointense cross-sectional area. Histologically, there were isolated islands of muscle, adipose, loose connective tissue and dense collagenous partitions, organized in two separate bundles that extended through the full length of the suspensory ligament origin and body to the level of its bifurcation. Comparison of MR images with corresponding histologic sections confirmed that islands of heterogenous signal intensity in normal suspensory ligaments correlated well with these bundles. Using ultrasonography, it was impossible to distinguish these islands from surrounding dense collagenous tissue consistently. MR imaging determined the cross-sectional area of the suspensory ligament more accurately than ultrasonography. Based upon these results, MR imaging is superior to ultrasonography for assessment of the suspensory ligament. The appearance associated with normal ligament anatomy needs to be understood before MR signal variation can be considered as indicative of disease in the suspensory ligament.