Orthopedics

SSLD and PIPJ OA frequently go hand in hand

A recent study found that horses with proximal interphalangeal joint osteoarthritis (PIPJ OA) often have concurrent sesamoidean ligament desmopathy (SSLD).

Therefore, it might help to also evaluate the soft tissue structures of the pastern region in horses with more marked radiographic changes of the sesamoidean ligament, if they are not responding to treatment (Equine Vet J 2026 July 1. Published online first).

SSLD frequently occurs alongside PIPJ OA, according to the researchers, and there was some correlation between severity of the 2 conditions among 46.7% of the equids.

Even though PIPJ OA is common in the equine athlete, veterinarians rarely evaluate the supporting soft tissue structures surrounding the joint when they suspect SSLD, according to the researchers.

The researchers performed a retrospective clinical study because they wanted to know the prevalence of SSLD in horses with PIPJ OA.

They included 58 horses that had diagnostic imaging of the surrounding soft tissue structures with either ultrasonography or magnetic resonance imaging (MRI).

Two board-certified radiologists evaluated the imaging from 60 limbs. They reviewed the imaging of 22 Warmbloods, 19 Quarterhorses, 6 Thoroughbreds, 5 Arabians, 3 Appaloosas (5%) and 1 each from a Friesian, Paint horse and mule.

The radiologists graded the SSLD and PIPJ OA as absent, mild, moderate, or severe. They found that 28 animals had concurrent SSLD. There was a significant, fair-positive correlation between PIPJ OA severity and SSLD severity (P=0.015).

However, there was no correlation between lameness severity and the presence of SSLD in horses with PIPJ OA (P=0.37), the researchers said.

“SSLD frequently occurs alongside PIPJ OA, and there is a fair and significant correlation between SSLD severity and PIPJ OA severity. Evaluation of the soft tissue structures of the pastern region may be beneficial in horses with more marked radiographic changes, or those that do not respond to treatment as expected,” the researchers wrote. MeV