Warriors confirm Henry's broken kneecap

Warriors second-rower Ben Henry has been diagnosed with a broken patella in his left knee, but cleared of ligament damage.

Warriors second-rower Ben Henry has been diagnosed with a broken patella in his left knee. (AAP)

Warriors second-rower Ben Henry has been diagnosed with a broken patella in his left knee, but it's not clear how long he'll be sidelined.

Henry underwent surgery on Wednesday after being helped from the field midway through the first half of last Saturday's NRL loss to Wests Tigers.

His left leg was caught awkwardly while making a tackle in his first NRL game in almost a year.

It was feared he'd damaged knee ligaments or ruptured a quadricep muscle, but surgery cleared Henry of those complications, according to the Warriors' website.

It's expected Henry still faces a lengthy recovery period for the broken kneecap.

"Club medical staff say it is still too early to forecast Henry's full recovery," said the club statement.

The 24-year-old had two knee reconstructions after season-ending ACL injuries to his left knee in 2013 and 2015.