Pathology of Articular Cartilage and Synovial Membrane From Elbow Joints With and Without Degenerative Joint Disease in Domestic Cats

Abstract

The elbow joint is one of the feline appendicular joints most commonly and severely affected by degenerative joint disease. The macroscopic and histopathological lesions of the elbow joints of 30 adult cats were evaluated immediately after euthanasia. Macroscopic evidence of degenerative joint disease was found in 22 of 30 cats (39 elbow joints) (73.33% cats; 65% elbow joints), and macroscopic cartilage erosion ranged from mild fibrillation to complete ulceration of the hyaline cartilage with exposure of the subchondral bone. Distribution of the lesions in the cartilage indicated the presence of medial compartment joint disease (most severe lesions located in the medial coronoid process of the ulna and medial humeral epicondyle). Synovitis scores were mild overall and correlated only weakly with macroscopic cartilage damage. Intra-articular osteochondral fragments either free or attached to the synovium were found in 10 joints. Macroscopic or histologic evidence of a fragmented coronoid process was not found even in those cases with intra-articular osteochondral fragments. Lesions observed in these animals are most consistent with synovial osteochondromatosis secondary to degenerative joint disease. The pathogenesis for the medial compartmentalization of these lesions has not been established, but a fragmented medial coronoid process or osteochondritis dissecans does not appear to play a role.

Do cats with a cranial cruciate ligament injury and osteoarthritis demonstrate a different gait pattern and behaviour compared to sound cats?

“…However, these conclusions appear to be based on the aetiology of OA in dogs and may not be applicable in the cat. For example, recent information in cats has indicated that they do not appear to suffer from fragmented coronoid process, the most common cause of elbow OA in dogs [ 23 ]. In human patients, obesity is regarded as a predisposing factor for OA [ 24 , 25 ].…”

Micromorphology and topography of tarsal joint capsule's vascular elements in cats and dogs

“…The fastest reparative and regenerative processes take place in tissues with high blood supply (Freire, Meuten, & Lascelles, 2014).…”

“…The fastest reparative and regenerative processes take place in tissues with high blood supply (Freire, Meuten, & Lascelles, 2014). Saturation of tissues with vascular elements provides a high level of metabolic activity and ability to recover (Beever, Giles, & Meeson, 2017).…”

Evaluation of serum cytokines in cats with and without degenerative joint disease and associated pain

“…The cytokines found to be elevated in this study have many potential sources, including peripheral leukocytes or local sources such as monocytes/macrophages, synovial cells, or chondrocytes in the affected joints. While synovitis in degenerative elbow joints in cats has been shown to be relatively mild (Freire et al, 2014), synovitis in OA in people is also typically scored as mild-moderate, and yet there is recognition of the inflammatory component to the disease (Berenbaum, 2013). Toll-like receptor 4 (TLR4) has been particularly implicated in contributing to inflammation in DJD/OA, with increased TLR4 expression in areas of damaged cartilage in patients with OA (Kim et al, 2006).…”