MusculoskeletalPending review

Osteoarthritis

A mechanical disease in which cartilage breakdown outpaces chondrocyte repair, leaving a failing joint that remodels bone and hurts most with the use that drives the wear.

First principles

Osteoarthritis is a failure of repair, not primarily an inflammatory disease

Articular cartilage is constantly being damaged by mechanical load and constantly repaired by chondrocytes. Osteoarthritis develops when that balance tips: through age-related decline in chondrocyte repair capacity, obesity and malalignment raising the load, or prior trauma damaging the joint surface. Once cartilage loss outpaces repair, the smooth, low-friction surface thins and fibrillates, exposing the bone beneath. This is why osteoarthritis is best understood as a mechanical, degenerative process rather than a primarily immune-driven one, even though secondary low-grade inflammation contributes to pain.

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Educational content pending clinical review. Not medical advice.