Okafor is to begin rehab work to reduce the inflammation in the neck area. Tests revealed the injury after he experienced pain.
Okafor averaged 9.7 points and 8.8 rebounds in 79 games last season for the Wizards.
Meanwhile, forward Chris Singleton is scheduled for outpatient surgery on Wednesday to repair a fracture to the fifth metatarsal in his left foot.
Singleton's recovery time will be approximately six to eight weeks. The Wizards open the regular season on October 30 against the Detroit Pistons in Auburn Hills.
Singleton was hurt Tuesday during a voluntary workout at the Verizon Center. X-rays detected a fracture, which was to be repaired by team physicians Dr. Marc Connell and Dr. Ed Magur.
Detroit Pistons forward Charlie Villanueva has testified before a jury in New Jersey that former Connecticut player Tate George misused money he had invested with George's company.
Villanueva, who also played at UConn, said he invested $250,000 with George and was promised a return of $37,500 plus 2 per cent of gross profits for years. But he never received any money, included the $250,000, from his investment in a real-estate project in Bridgeport, Conn.
Villanueva told The Trentonian after leaving the courthouse that he was particularly hurt that a former fellow UConn player had conned him.
"And it's $250,000," Villanueva said. "That could have gone to my son's education."
New Jersey prosecutors allege that George was running what amounted to a Ponzi scheme. He is on trial in US District Court for wire fraud that netted him $2 million.
George is most remembered for his buzzer-beater that gave UConn a victory over Clemson in a Sweet 16 game in the 1990 NCAA Tournament.