"Huge thank you to @theparraeels for supporting me through this. I'm not sure where 2022 will take me but I'm excited to see what the next chapter holds."
Hipgrave's Instagram post garnered support from Eels fans as well as from fellow NRL stars Connor Watson, Jahrome Hughes, Reagan Campbell-Gillard and Nathan Brown among others.
Hipgrave retires with 49 first-grade appearances to his name, having made his NRL debut with the Gold Coast Titans in 2017.
After four seasons on the glitter strip, he moved to Parramatta, where he made nine appearances this year, mostly from the bench.
The Eels said they were committed to supporting Hipgrave in his transition into retirement.
"Keegan has been a wonderful addition to our club and a very popular member of the team," Parramatta Eels general manager of football Mark O'Neill said.
"While it's a shame his career has prematurely come to an end due to injury, the health and wellbeing of our players is always our first priority."