Equine meniscal degeneration is associated with medial femorotibial osteoarthritis.

The research paper focuses on understanding the normal morphology of equine meniscus, its degeneration, and the role it plays in osteoarthritis (OA). The study provides first-time insights into these aspects and reveals significant correlation between meniscal degeneration and OA severity in the medial femorotibial joint of horses.

Objective and Methods used in the research

The research had two main objectives:

• Characterize normal equine meniscal morphology and lesions
• Understand the relationship between equine meniscal degeneration and femorotibial OA.

To fulfill these objectives, menisci from 7 normal joints and 15 joints with OA were harvested from ex vivo cadaveric study. A score was used to measure OA severity considering cartilage degeneration and osteophytosis. The femoral and tibial meniscal surfaces were evaluated for macroscopic fibrillation and tears with a specific scoring system. Finally, histological sections were scored for microscopic fibrillation, tears, and inner border degeneration.

Results of the study

The study revealed that partial meniscal tears were present on both femoral and tibial surfaces in all 3 regions. These were most frequently identified on the femoral surface of the cranial horn of the medial meniscus and body of the lateral meniscus.

A significant positive correlation was found between the global medial meniscal macroscopic scores and the osteophyte or cartilage degeneration scores within the medial femorotibial joint. In addition, the global medial meniscal macroscopic score was found to be higher in advanced OA joints compared with the control joints.

The important conclusions drawn from the research

The research provided the first-ever characterization of normal equine meniscal morphology and lesions. It was found that meniscal lesions were identified in all segments and on both articular surfaces. Furthermore, a significant correlation was found between meniscal degeneration and OA severity in the equine medial femorotibial joint. However, further study is needed to elucidate the precise relationship between OA and meniscal pathology.

Note: The study relied on abattoir specimens without a known clinical history due to the challenge in obtaining a large number of specimens with a clinical diagnosis of femorotibial OA.