Chronic eosinophilic granulomatous tenosynovitis in a Quarter Horse mare
Authors: Williams Zoë J., McIlmurray John, Nickels Frank
Journal: Equine Veterinary Education
Summary
# Editorial Summary A five-year-old Quarter Horse mare presenting with grade 4/5 lameness and right hind metatarsophalangeal joint swelling was found on radiography and ultrasonography to have peritendinous mineralisation and severe digital flexor tenosynovitis with intracapsular calcification. Tenoscopy revealed extensive tan granular material within the digital tendon sheath—approximately 80% of which was successfully removed—with histopathology confirming a diagnosis of eosinophilic granulomatous tenosynovitis, a rare condition involving inflammatory cell infiltration and foreign-body-type reactions within synovial structures. Surgical treatment combined plantar annular ligament desmotomy and manica flexoria ligament tenotomy, with post-operative management including four intralesional triamcinolone injections administered at 2–4 week intervals. By five months post-tenoscopy, the mare had improved to grade 1/5 lameness and was undertaking light ridden work, demonstrating that early surgical debridement combined with targeted intra-lesional corticosteroid therapy can achieve serviceable soundness in this otherwise debilitating condition. This case highlights the diagnostic utility of tenoscopy for definitive tissue characterisation in chronic tenosynovitis and the potential value of serial intralesional corticosteroid treatment in managing eosinophilic granulomatous inflammation when conventional therapies may be insufficient.
Read the full abstract on the publisher's site
Practical Takeaways
- •Eosinophilic granulomatous tenosynovitis should be considered in cases of severe digital flexor tenosynovitis with unusual mineralisation patterns; diagnostic tenoscopy can provide tissue samples for histopathological confirmation
- •Surgical debridement combined with post-operative intralesional corticosteroid therapy may achieve functional soundness and return to light work, though this is a rare condition with limited comparative data
- •Long-term follow-up and repeated corticosteroid treatments spaced 2-4 weeks apart appear beneficial for managing this inflammatory condition
Key Findings
- •Eosinophilic granulomatous tenosynovitis presented as grade 4/5 lameness with intracapsular mineralization of the digital flexor tendon sheath in a Quarter Horse mare
- •Tenoscopy with plantar annular ligament desmotomy and manica flexoria ligament tenotomy removed approximately 80% of granular material from the tendon sheath
- •Four intralesional triamcinolone injections administered 2-4 weeks apart resulted in improvement to serviceability (grade 1/5 lameness) within 5 months post-surgery