Essentially, 45.6% of players with that injury never return to NFL action. And nearly 80% of players didn't return within two seasons.
https://ftw.usatoday.com/story/sports/nfl/2025/08/07/rashawn-slater-tears-patellar-tendon-timeline-to-return-injury/85567450007/#:~:text=The overall RTP for PT,Featured Weekly Ad
Yep its worse much worse than an ACL tendons always are, think Achilles tendon except instead of explosiveness loss its complete loss of a knee.