Wizards center Dwight Howard underwent back surgery on Friday. (Al Drago/Associated Press)

Washington Wizards center Dwight Howard underwent surgery on his lower back Friday, the team announced, and could be out up to three months.

Howard has been dealing with what the Wizards have described as “gluteal soreness,” and the injury had impinged his lower body movement throughout the season, limiting him to nine of the Wizards' first 21 games. However the procedure, an L4-L5 lumbar microdiscectomy performed by Robert Watkins in Marina Del Ray, Calif., was to mend the lower disk in his vertebrae. In 2012, Howard had a similar surgery done by Watkins to repair a herniated disk in his back.

According to Payam Farjoodi, an orthopedic spine surgeon who has formerly worked with the Baltimore Orioles but has not consulted with Howard, it is likely that Howard’s disk had re-herniated and pushed up against the nerve, causing irritation and pain that shot into his lower back, buttocks and down the back of his leg.

The team will reevaluate Howard in approximately two to three months, meaning the earliest assessment date in Howard’s rehabilitation would be Jan. 30, when the Wizards are scheduled to play their 51st game of the 82-game regular season.

“He has been missed and he will be missed," Coach Scott Brooks said Friday before the Wizards faced the Philadelphia 76ers, "but we have to move forward and play without him and do the best we can, and I think guys are going to step up.”

The spinal procedure further interrupts Howard’s debut season in Washington, which has been limited from the beginning. He is averaging 12.8 points and 9.2 rebounds.

In July, Howard, 32, signed a two-year deal for approximately $11 million and a player option for the second year. An eight-time all-star, Howard was supposed to replace longtime starter Marcin Gortat, who was traded to the Los Angeles Clippers, and provide the team with the most athleticism it has had at that position since John Wall became the starting point guard in 2010.

“That’s the part going into the summer, we obviously had a game plan with Dwight being in the mix and shoring up our rim protecting and rebounding issues and then obviously his ability to catch lobs and finish around the rim,” Brooks said. "But we didn’t have him for training camp and we didn’t have him but for eight or nine games this year, so we have to just keep rebounding by committee.”

Howard missed all of preseason, with the Wizards first describing his ailment as back soreness. It wasn’t until Howard visited a specialist in New York on Oct. 8 that he was diagnosed with piriformis syndrome. Following the visit, Howard received a pain-relieving injection and missed the first seven games of the regular season.

“A lot of people don’t understand what piriformis syndrome is,” Howard said ahead of his Nov. 2 season debut. “We said it was ‘gluteal soreness,’ so everybody was thinking that it’s something small, but what I had was very painful and it was something that really kept me away from doing what I love the best, which is playing basketball.”

Farjoodi, however, says in his experience piriformis syndrome is a rare occurrence.

“We diagnose it when we can’t figure out what else is going on," said Farjoodi, not speaking specifically about Howard’s situation.

Farjoodi suspects Howard had been dealing with a disk injury all along, which explains the specific pain as it related to sitting down for long stretches. When Howard rested during games, he stood on the sideline rather than sitting. He rarely flashed his past athleticism, and his jumping ability was impacted.

Ahead of Washington’s Nov. 18 game against the Portland Trail Blazers, Howard could not sit in front of his locker to pull up his socks without experiencing discomfort. On that night, he said he planned to try a new treatment for his injury after other pain-relieving options had failed.

Howard played seven minutes in that game before returning to the bench and eventually leaving for the locker room. In his absence, the Wizards have promoted second-year center Thomas Bryant to the starting lineup, while veterans Markieff Morris and Jeff Green also play in his spot in reserve roles.

Prior to Howard’s surgery, Morris campaigned for Bryant to remain in the starting five even when Howard returned.

"When Dwight comes back, whenever he does,” Morris said, “if we winning — I mean, he’s a great player — but honestly, I think we should go with the hot hand like we doing now with me coming off the bench. I just think [we should] go with the momentum.”

Backup center Ian Mahinmi had not played in six consecutive games but is expected to help fill the void in the team’s lack of depth at the center position.

“It’s a big loss [in] losing a big-time player. Obviously when this team was put together this summer, bringing Dwight was a big deal,” Mahinmi said. "At this point it’s not about one individual player. It’s about this team right here and finding ways to play better and win games.”

After the first surgery in 2012, Howard remained in the Los Angeles area for several weeks to be near Watkins. Although Brooks did not say if Howard will stay in Los Angeles for an extended amount of time, Farjoodi said it is common for a patient not to fly for at least two weeks following this procedure.

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