Sen. Robert Byrd — the longest-serving Senator of Congress — did not suffer any broken bones when he fell inside his home on Monday, a spokesman tells FOX News.

Byrd spokesman Jesse Jacobs said follow-up X-rays showed that Byrd did not suffer any fractures, but will undergo physical therapy at Walter Reed Army Medical Center in Washington, D.C., to improve hi stability. Byrd intends to return to Senate duties next week.

Byrd, 90, is serving his ninth term in the Senate. As Senate president pro tempore, Byrd is third in line to the presidency.

FOX News' Trish Turner contributed to this report.