Hinchcliffe's left upper thigh and pelvic area was pierced by a piece of his car's suspension piece in Monday's ferocious crash at Indianapolis Motor Speedway, and he had significant blood loss before surgery at IU Health Methodist Hospital.
But Hinchcliffe was doing well enough in the first 48 hours after the accident to be transferred out of intensive care, and he won't require additional procedures.
"We're very pleased with his progress and his condition continues to improve," said Dr. Timothy Pohlman, senior staff trauma surgeon at Methodist.
Hinchcliffe's car will be driven in Sunday's Indianapolis 500 by Ryan Briscoe, a nine-year veteran of the race who sat on the pole in 2012 and has been a front-row starter two additional years. He has twice finished fifth.
Briscoe spent most of Wednesday at the Schmidt Peterson Motorsports facility north of IMS. He has never driven for the team, although he was under consideration for a ride before the season began.
Briscoe could not be reached for comment because the team has scheduled a Thursday news conference to discuss weekend plans. One of the issues is getting Briscoe time on the track ahead of Friday's one-hour Carb Day practice (11 a.m.). IndyCar president Derrick Walker said he is examining schedules.
Indy Lights will practice and qualify Thursday in preparation for Friday's Freedom 100, a 100-mile race at IMS.
Briscoe will join fellow Australian James Davison as a late addition to the 500's 33-car lineup. Davison missed qualifying due to a prior commitment; Tristan Vautier qualified the Dale Coyne Racing car for him. Assuming there are no other driver changes, Briscoe will start 32nd and Davison 33rd based on IndyCar Series entrant points. Other drivers will move up one spot accordingly.
A piece of the suspension made of steel drove through Hinchcliffe's leg, but that's not what caused him to crash. Walker confirmed it was a standard Dallara-made connecting component known as a rocker, and it was one of the older ones used by IndyCar Series teams. Once the failure was identified, Walker said all teams were encouraged to switch to the latest generation of rockers.
Walker did not blame the manufacturer or the team, although he acknowledged the rocker had been used longer than some.
"What Dallara calls for is that you check them on a regular basis and you replace the bearings," he said. "There wasn't an actual mileage (restriction) and then you throw it away."
Walker expects IndyCar to establish new mileage guidelines, but that's more out of precaution than necessity.
"The component was not known to be one of those (troublesome) parts," he said. "You keep an eye on it and you (test) it on a regular basis it should be OK.
"But for some reason this one didn't make it." Indy Star