Augmented pain behavioural responses to intra-articular injection of nerve growth factor in two animal models of osteoarthritis.

Objectives: Nerve growth factor (NGF) is a promising analgesic target, particularly in osteoarthritis (OA) where existing therapies are inadequate. We hypothesised that pain responses to NGF are increased in OA joints. Here, NGF-evoked pain behaviour was compared in two rodent models of OA, and possible mechanisms underlying altered pain responses were examined.

Increased vascular penetration and nerve growth in the meniscus: a potential source of pain in osteoarthritis.

Objectives: Meniscal damage is a recognised feature of knee osteoarthritis (OA), although its clinical relevance remains uncertain. This study describes vascular penetration and nerve growth in human menisci, providing a potential mechanism for the genesis of pain in knee OA.

Methods: Menisci obtained post mortem were screened on the basis of high or low macroscopic tibiofemoral chondropathy as a measure of the presence and degree of OA.