Maddox's injury was diagnosed as a "non-surgical" ailment, which means the veteran quarterback may return this season.
Maddox has been advised not to throw for approximately six weeks, and he will be re-evaluated at that time. His return to active duty will be determined following the six weeks.
Tests revealed some ligament and tendon damage in his right elbow.
In the meantime, the Steelers will explore adding another quarterback to the roster, according to Coach Bill Cowher.
"We are seeing what our options are," Cowher said. "We will bring in another quarterback to our team. In what capacity, at this point, we have not determined."
Rookie quarterback and 2004 number-one draft pick Ben Roethlisberger has been named the starter. Roethlisberger replaced Maddox for virtually the entire second half of last Sunday's Baltimore game. Second-year quarterback Brian St. Pierre was added to the active roster this past Saturday as insurance for Roethlisberger, who injured his knee in practice last week.
To make room for St. Pierre the Steelers waived veteran wide receiver Chris Doering.