Disease progression including natural history, disease phases or stages, disease trajectory (clinical features and presentation over time)
- New onset/acute
- The initial cycle could begin as tendinitis with inflammation of the tendon or paratenon, followed by a blunted inflammatory process. Onset may be acute, traumatic, or insidious, presenting as an acute tear, often related to unaccustomed activity or a single instance of exertion. The healing process may be altered due to relative ischemic or other factors.
- The variant of calcific tendinosis (calcific tendinitis) is a hydroxyapatite crystaline deposition into tendon, often affecting specific tendons such as the supraspinatus, and progresses through stages including fibrocartilage ingrowth, calcium formation, resorption and healing.
- The subacute or chronic nature of tendinopathy repeats the blunted inflammatory cycle resulting in a thickened and degenerated tendon that is more prone to pain or an acute tear.