Proximal suspensory desmitis: clinical, ultrasonographic and radiographic features.

The study focuses on the characteristics of proximal suspensory desmitis, a condition affecting the suspensory ligaments in horses’ forelimbs and hindlimbs, using clinical examinations, ultrasound imaging, and radiographic imaging.

Clinical Presentation

• Proximal suspensory desmitis refers to inflammation of the suspensory ligament of the horse’s leg, near the area where the ligament attaches to the bone.
• Typically, acute cases show moderate swelling, warmth, and distension of the medial palmar vein (the vein located along the palm side of the leg). Pain may also be present, but this is often subtle and can be difficult to pinpoint without the use of local anesthesia.
• In chronic cases or situations where the horse was rested immediately after the onset of lameness, these physical signs may not be evident despite the horse’s discomfort.

Ultrasonographic and Radiographic Findings

• The researchers found that transverse ultrasonographic imaging — imaging that cuts across the suspensory ligament — provided the most useful information for diagnosing this condition. Various abnormalities were observed, including enlargement of the ligament, poorly defined boundaries especially toward the dorsal (top) side, and different types of changes in the ligament’s echo-texture (the pattern seen on the ultrasound image).
• Radiographic imaging revealed that abnormalities were seen more frequently in the hindlimbs than in the forelimbs. These changes included hardening of the bone’s interior structure, changes in the orientation of these structures, and outgrowth of bone at the ligament insertion point.
• The most extensive radiographic abnormalities were associated with Type V ultrasonographic lesions, where a considerable area of the ligament exhibited altered echo-texture.

Prognosis

• According to the study, the prospects for an affected horse returning to full athletic function and maintaining long-term soundness were better if the horse had the injury in the forelimb rather than the hindlimb.
• This prognosis was particularly true when the ultrasonographic image showed resolution — meaning the ligament’s appearance returned to normal after treatment.