Pain modulatory network is influenced by sex and age in a healthy state and during osteoarthritis progression in rats.

Old age and female sex are risk factors for the development of osteoarthritis (OA) and chronic pain. We investigated the effects of sex and age on pain modulatory networks in a healthy state and during OA progression. We used functional MRI to determine the effects of sex and age on periaqueductal gray functional connectivity (PAG FC) in a healthy state (pre-OA) and during the early and late phases of monosodium iodoacetate-induced OA in rats.