An OA phenotype may obtain major benefit from bone-acting agents

Association of COL1A1 polymorphism with subchondral bone degeneration of the temporomandibular joint

“…Although OA is inversely related to osteoporosis, some patients with TMJ OA present osteoporosis-like lesions (low-density lesions). 5,25,26 The enhancement of bone turnover and further loss of bone mass, characterized by low-density lesions, are the primary pathological changes in OA. 5 Osteoporosis-like lesions evidently aggravate the progression of OA.…”

“…5,25,26 The enhancement of bone turnover and further loss of bone mass, characterized by low-density lesions, are the primary pathological changes in OA. 5 Osteoporosis-like lesions evidently aggravate the progression of OA. 26 OA-related changes in the subchondral bone, and weakened subchondral cortical plate and trabeculae, may lead to deformation of the joint surfaces and alterations to local absorption; as a result, osteoporosis presents as a decrease in BMD.…”

“…4 Changes in the subchondral bone may also play a pivotal role in TMJ damage during the induction and progression of OA. 5 In cone beam tomography (CBCT) images, subchondral osseous changes in the condyles are usually manifested as low-density lesions (erosion, resorption, or cyst-like lesions) or high-density lesions (sclerosis). 3 The enhancement of bone turnover and further loss of bone mass, seen as cortical bone erosion, condylar head resorption, or cystlike lesions, are thought to be the primary pathological changes in OA and the decrease in bone turnover and subsequent densification of bone shown as osteophyte formation and subchondral sclerosis.…”

“…3 The enhancement of bone turnover and further loss of bone mass, seen as cortical bone erosion, condylar head resorption, or cystlike lesions, are thought to be the primary pathological changes in OA and the decrease in bone turnover and subsequent densification of bone shown as osteophyte formation and subchondral sclerosis. 4,5 The extracellular matrix (ECM) collagen of subchondral bone is mainly composed of type I, with very small amounts of other collagen types, such as III, V, and VI. 4,6 Type I collagen is a heterotrimer consisting of two a1(I) and one a2(I) chains.…”

An update on the up and coming therapies to treat osteoarthritis, a multifaceted disease

“…The failure of SYSADOAs and other agents to show being specific treatments for OA that modify both symptoms and disease prosecution could be also ascribed to the fact that different phenotypes of OA may respond in a variable manner to different therapies. RCTs involving patients affected by "generic" OA may give controversial results in terms of treatment efficacy (44). In this sense, it may prove useful to discriminate among distinct clinical and etiopathogenic phenotypes, especially in the early stages of disease, before designing a RCT for the evaluation of efficacy and safety profiles of a given therapeutic tool.…”