Patellar tendinopathy is a degenerative disorder of the patellar tendon.
Repetitive springing up and landing stresses the attachment of the patellar tendon.
Instead, the tendon develops a mushy ('mucoid') degeneration, which weakens it, causes local discomfort, and may predispose the tendon to rupture.
The term '-itis' in medicine means 'inflammation' - a process of irritation, increased blood supply, and infiltration of the area with special inflammatory cells - but these features are not actually seen in patellar tendinitis.
So there is a lot of medical literature suggesting that the condition no longer be called 'patellar tendinitis' but 'patellar tendinopathy' or 'patellar tendinosis' instead, implying a degenerative condition rather than an inflammatory one. For your research, you need to search using all of these keywords.
"Patellar tendinopathy...has continued to challenge health care professionals...effective conservative intervention includes relative rest, addressing biomechanical issues, eccentric exercise, stretching, and movement retraining...TFM [Transverse friction massage] and counterforce bracing...have weak or little evidence to support their use...In the case of persistent tendon pain...injectables or surgery may be indicated."
Patellar tendinitis, Overuse injuries, Mucoid degeneration, Prolotherapy
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