New York (CNN) -- A Broadway actor injured when he fell more than 20 feet while performing a stunt in the "Spider-Man" musical is set to be released from a rehabilitation center this week, his father told CNN Sunday.
Christopher Tierney, 31, was moved into the center after being discharged from New York's Bellevue Hospital on December 28.
His father, Tim Tierney, said he isn't sure when his son will arrive at his Portsmouth, New Hampshire, home, but said he is scheduled to be released from the facility Wednesday.
Christopher Tierney suffered four broken ribs; a hairline skull fracture; a broken scapula, or shoulder blade; a bruised lung; three cracked vertebrae; and broken bones below his elbow in the December 20 fall, the elder Tierney has said.
Tim Tierney said his son is improving.
"He is up," he said. "He is walking and just doing very well." He said Christopher Tierney cannot wait to return to the show, "Spider-Man: Turn Off The Dark."
Several of the shows were canceled following Tierney's fall, and new safety precautions were put in place before they resumed following a meeting between the show's company, the Occupational Safety and Health Administration and the New York State Department of Labor.
The show, with music and lyrics by U2's Bono and Howell (aka The Edge), is the most expensive in Broadway history, but production has been beset by cast injuries and technical problems.
Once Christopher Tierney is home, his family plans a belated Christmas celebration, Tim Tierney said.
Jonathan Dealwis, a tourist from New Zealand, said he saw Tierney fall.
"Spider-Man was on a bridge, and Mary Jane was dangling from it," he said. "I think he was meant to sort of swoop over there, but he just fell off ... the harness, you could see it just flick off his back and fly backward."
CNN's Ashley Vaughan contributed to this report.