Figure 1. Photograph (cranial-caudal) of a transverse sacropelvic anatomic section showing the right sacroiliac joint. Ultrasound-guided sacroiliac joint region injection was performed with methylene blue before dissection. Note the interosseous sacroiliac ligament (*) with some methylene blue staining, the ventral sacroiliac ligament (arrowhead) and the sacroiliac joint where the hyaline cartilage of the sacrum is stained with methylene blue. I=ilium; S=sacrum.

Diagnosis and treatment of sacroiliac joint region pain in horses

Sacroiliac joints are atypical diarthrodial joints, forming the articulation between the ventral aspect of the ilium and the sacral wing (Figure 1). The sacroiliac joint is angled at approximately 30°...