After initial X-rays were "reassuring," a follow-up CT scan showed that President-elect Joe Biden has hairline fractures in his foot following a fall this weekend, his doctor said.

Biden will likely need to wear a walking boot "for several weeks," Dr. Kevin O’Connor, the director of executive medicine at GW Medical Faculty Associates, said in a statement.

“Initial X-rays did not show any obvious fracture, but his clinical exam warranted more detailed imaging," O'Connor said in a statement. "Follow-up CT scan confirmed hairline (small) fractures of President-elect Biden’s lateral and intermediate cuneiform bones, which are in the mid-foot."

Biden fell over the weekend while playing with his dog.

President-elect Joe Biden suffered a sprained foot Saturday after slipping while playing with his dog, according to his doctor.

"Initial X-rays are reassuring that there is no obvious fracture and he will be getting an additional CT for more detailed imaging," Dr. Kevin O’Connor said in a statement Sunday following the examination at the Delaware Imaging Network facility at the Omega Professional Center in Newark.

Biden slipped while playing with his dog, Major, and twisted his ankle.

Biden and Vice President-elect Kamala Harris announced on Sunday seven top members of the White House senior communications staff, all of whom are female.

Jen Psaki, who served as communications director during the Obama administration and has been working as a spokeswoman for the transition, will be the White House press secretary

Kate Bedingfield, who served as the Biden campaign's communications director, will assume the same title in the White House.

Karine Jean-Pierre, who was a senior advisor to Biden's campaign, will serve as the principal deputy press secretary.

Pili Tobar, who was the Biden campaign's communications director for coalitions, will be the deputy White House communications director.

Other hires announced Sunday include Symone Sanders, a senior campaign adviser, who will be the chief spokeswoman for Harris, Ashley Etienne who will be Harris' communications director, and Elizabeth Alexander, who will be first lady Jill Biden's communications director.

-ABC News' John Verhovek

Biden slipped while playing with his dog Major, and twisted his ankle on Saturday. Out of an abundance of caution, he will be examined this afternoon by an orthopedist.

-ABC News' John Verhovek

Another court ruling has gone against allies of the Trump campaign in their bid to halt certification of the 2020 presidential election in Pennsylvania, as the state's Supreme Court issued an order Saturday dismissing a recent court challenge focused on mail-in voting.

This election challenge was brought by U.S. Rep. Mike Kelly, a Republican, along with another GOP candidate for Congress, alleging that the state legislature had not legally passed the measure allowing for universal mail-in voting.

The plaintiffs called on the court to have Pennsylvania Secretary of State Kathy Boockvar cancel all mail-in ballots or, if not, to empower the state legislature to appoint new electors. A trial judge on Tuesday had imposed a temporary injunction to pause the election certification process until the question could be resolved. Boockvar's office brought the matter immediately to the state Supreme Court.

The Pennsylvania Supreme Court vacated the injunction on Saturday and dismissed the case with prejudice, meaning the GOP cannot bring it back.

-ABC News' Matthew Mosk and Alex Hosenball