pannus formation
Pronunciation: PAN-us
Development of inflammatory granulation tissue that invades and destroys joint cartilage and bone in chronic pediatric arthritis.
Full Definition
Pannus formation represents the development of aggressive inflammatory tissue composed of proliferating synovial cells, inflammatory cells, and blood vessels that invades joint cartilage and subchondral bone. This process is a hallmark of severe, chronic inflammatory arthritis in children and represents the mechanism by which joints become permanently damaged. Pannus appears on imaging as enhancing soft tissue masses that erode into bone and cartilage. Recognition of pannus formation indicates advanced disease requiring aggressive treatment to prevent further joint destruction. The term derives from the Latin word for cloth, describing the tissue's appearance covering joint surfaces.
Usage
Usage note: Indicates severe, destructive disease; distinguish from reversible synovial inflammation.
In Context
- "MRI revealed pannus formation with erosive changes at the metacarpophalangeal joints." — Advanced imaging report
- "The presence of pannus formation indicated the need for immediate biologic therapy to halt joint destruction." — Treatment escalation note