Desmitis of the palmar or plantar ligaments of the proximal interphalangeal joint: A descriptive case series.

The study explores the desmitis, or inflammation, of specific ligaments in a horse’s foot, and how this condition is linked to lameness in horses. Using magnetic resonance imaging, the researchers identify the common features of this condition, shed light on the challenges in differentiating ligaments, and suggest that it should be closely examined in cases of lameness.

About the Study

• This research paper reports a descriptive case study on desmitis or inflammation of one particular tendons or ligament group in horses, specifically focusing on the palmar/plantar ligaments of the proximal interphalangeal joint (PL-PIPJ).
• The study’s aim is two-fold: First, it tries to demarcate and identify PL-PIPJ ligaments on low-field magnetic resonance (MR) scans. Secondly, it investigates and describes injury characteristics of these ligaments on MR scan and how the ligament injury symptoms correlate with clinical features and lameness in horses.
• The key method of research was a retrospective case study analysis utilizing data and MR images from 29 horses across three different institutions.

Results of the Study

• The study results concluded that differentiation between certain ligaments can be unreliable. For example, the abaxial palmar/plantar ligament was distinctly observable only 5% of the time.
• Incidence of PL-PIPJ desmitis was confirmed as the main MR finding in 45% of the clinical cases. It indicated this condition is a fairly common cause of lameness in horses.
• The study found that periligamentous edema, or swelling around the ligament, was evident in 74% of the abaxially located ligaments that had inflammation. The presence of this edema often suggested that inflammation is present.
• In 33% of cases with desmitis, there was enthesis formation within the ligaments, which is an abnormal bony growth at the attachment site of a tendon or ligament.

Conclusions and Implications

• The retrospective nature of this study and lack of a control group are some of its limitations.
• The results suggest that PL-PIPJ ligament injury can be a primary cause of lameness in horses, emphasizing the necessity of a thorough evaluation on MR examination.
• Differentiation between abaxially located structures tends to be challenging due to their close proximity.
• The presence of periligamentous oedema often indicates desmitis of the abaxially located ligaments, calling for more rigorous assessment if it’s observed.