J.J. Watt, a three-time NFL Defensive Player of the Year who played 12 NFL seasons and now works as a television commentator, posted his younger brother's status on social media.
"Yesterday, TJ had successful surgery to stabilize and repair a partially collapsed lung suffered on Wednesday after a dry needling treatment session at the facility," the elder Watt said of his brother.
"Recovery timeline is still TBD, but all went well and he is being released from the hospital today. He and his family are very appreciative of everyone's kind words and well wishes."
Dry needling is a treatment for pain and movement issues involving the insertion of tiny needles into the body.
Steelers coach Mike Tomlin said Friday that the 31-year-old Watt will miss Monday's game against Miami and is home and resting comfortably.
Watt signed a three-year contract extension worth $123 million in July with the Steelers, who carry a 7-6 record and the AFC North division lead into the final month of the campaign as they fight for a playoff berth.
Watt, the 2021 NFL Defensive Player of the Year, made six tackles in Pittsburgh's victory over Baltimore last Sunday. He has 53 tackles, seven sacks, three forced fumbles, two fumble recoveries, and an interception this season.
The Steelers said Thursday that Watt was taken to an area hospital for a lung evaluation after feeling discomfort Wednesday at the team's facility.