Tendon and joint injuries in the horse

What are tendon and joint injuries in the horse?

Tendon and joint injuries are among the most common causes of lameness and early retirement in sport horses. The superficial digital flexor tendon (SDFT) is most frequently affected: in 75–93% of cases in athletic horses, typically at the level of the middle of the metacarpal region [3]. Tendon injury is often the result of overload, after which a sometimes extensive core lesion develops that requires long-term rehabilitation.

Diagnosis

Ultrasonography is the gold standard for both diagnosis and rehabilitation guidance. The size of a core lesion on initial ultrasonographic examination is the strongest prognostic factor: with more than 50% cross-sectional involvement, the prognosis is significantly worse. In racehorses, only 31% return successfully to the same level after an SDFT injury; switching to a lower discipline is frequent [3].

Additional treatment options

PRP (platelet-rich plasma)

PRP injections are the best-researched biological intervention for equine tendon and ligament injuries. Systematic research shows a lameness reduction of 30–60% in treated horses, versus 10–25% in control animals [1]. Return-to-sport percentages also improve. However, the evidence is not unequivocal: the large variation in PRP preparation methods makes it difficult to compare or standardise protocols. PRP is an addition to — not a replacement for — classical rehabilitation and veterinary supervision [1][2].

Stem cell therapy (MSC)

Treatment with mesenchymal stem cells shows increasing evidence in systematic reviews, but controlled clinical studies in horses are scarce [2]. Combined PRP+MSC treatments yield inconsistent results. Stem cell therapy is currently considered experimental; discuss the option with a specialised equine veterinary surgeon.

Intra-articular corticosteroids

Corticosteroids are effective for joint disorders (arthritis, synovitis) and are widely used. Long-term or frequent use can be chondrotoxic — that is, harmful to the cartilage. Always use under veterinary supervision, with a cautious repetition schedule.

Controlled rehabilitation

The cornerstone of recovery remains controlled load buildup over 12–18 months. Returning to sport too early is the primary cause of recurrence. Ultrasonographic controls guide the pace of recovery [3].

What is (not yet) proven to work?

Various supplements — such as MSM, collagen and herbal preparations — are used for tendon and joint complaints in horses, but clinical evidence from controlled studies is currently lacking. This does not automatically mean they do not work, but honest advice requires that this be stated.

Additional ≠ replacement

Biological therapies such as PRP are valuable additions for tendon and joint recovery, but never replace a thorough diagnostic workup, ultrasonographic monitoring and a careful rehabilitation programme under veterinary supervision. In acute or severe injuries, immediate veterinary contact is always the first step.