Histological characterization of cyst development in a rodent model of Osteoarthritis. Immunohistochemistry revealed an active bone remodeling response within the subchondral bone cysts (SBC), as the anterior cruciate ligament transection with partial medical menisectomy (ACLX - a, c, e) knees showed greater staining for markers of both resorption (Cathepsin K, a-arrow), and bone formation (Alkaline phosphatase, c-arrowheads) against the un-operated knees of the same animals (LEFT, b, d, f). Hematoxylin and eosin staining (e, f) showed the SBC (3 months post-ACLX) as a fibrous cavity, with fibrotic bone marrow in the ACLX knee (e-arrowheads). Scale bar = 250 μm.
McErlain et al. Arthritis Research & Therapy 2012 14:R26 doi:10.1186/ar3727