CHICAGO - Jockey Rene Douglas, injured badly in a spill Saturday at Arlington Park, underwent what was termed successful surgery to repair back and neck injuries early Sunday morning at Northwestern Memorial Hospital in Chicago. But Douglas remained paralyzed in the lower part of his legs, the long-term repercussions of his injuries may not be known for two weeks, and Douglas's prognosis is day-to-day, according to Doreen Razo. Razo, the wife of jockey Eddie Razo and a good friend of Douglas's wife, Natalie, was at Northwest Hospital in Arlington Heights, to which Douglas was taken after going down in the Arlington Matron, and with him at Northwestern, where the surgery was performed between 2:30 and 9:30 a.m. Sunday. Douglas, 42, responded well after coming out of sedation following his surgery Sunday afternoon, said Razo, and squeezed hands with others in his intensive-care-unit room when prompted to do so. Douglas is fitted with a breathing tube because of several broken ribs, and so cannot speak. But Razo said Douglas was "as responsive as they wanted him to be" when assessed by medical personnel after his surgery before being sedated again Sunday night. The surgery, which required an incision from neck to buttocks, took seven hours, but had been expected to last as much as 2 1/2 hours longer. Screws were inserted to stabilize two fractures in vertebrae at Douglas's neck; that injury is serious, but it was Douglas's other spinal injury, to the thoracic discs lower on his spine, that is the more consequential. Razo said that Douglas had compressed the T-5 and T-6 vertebrae in his back. "The T-5 got jammed into the T-6, and that put pressure on the spinal cord," Razo said. With three doctors present during the surgery, the vertebrae were decompressed and then fused. This procedure was deemed successful, but until inflammation and trauma to the area subside, long-term assessment remains difficult. Douglas will spend two weeks in the ICU before being transferred to a Northwestern rehabilitation clinic. Douglas went down at the top of the Arlington homestretch while riding Born to Be in the Matron, race 9 of 11 Saturday at Arlington. Racing just in behind the lead pack, Born to Be appeared to be running evenly or tiring when she turned into the stretch. She was about two paths off the rail when jockey Jamie Theriot on rail-skimming Sky Mom swung out and tried to go through a hole between Born to Be and eventual winner Euphony. Sky Mom bumped Born to Be, who was pushed out and clipped heels with tiring pacesetter Boudoir. Born to Be completely lost her footing, fell, and flipped over, rolling onto Douglas, who remained pinned beneath the horse until he was extricated by track personnel. Douglas was taken by ambulance to Northwest, where tests immediately were performed. When the nature of Douglas's injuries came into focus, Dr. Hilton Gordon and Richard Duchossois, Arlington's chairman, arranged for his transport to Northwestern Memorial. Douglas was flown by helicopter to Cook County Hospital, then driven 10 minutes to Northwestern. Razo phoned Douglas's wife in Fort Lauderdale, Fla., and Natalie Douglas quickly flew to Chicago and spoke to Douglas before he was taken to surgery. Douglas has three children - an 18-year-old from a previous relationship, and two other children, 13 and 8, with Natalie Douglas. On Monday, after holding a hearing on the matter Sunday, stewards at Arlington handed Churchill Downs-based Theriot a harsh 30-day suspension for jostling Born to Be with Sky Mom. Fred Aime, Theriot's agent, said that as of Monday, Theriot hadn't decided whether he would appeal the ruling. Aime said Theriot felt the weight of the accident when he went back to work Sunday. "He's got to go out and ride the horses, but he feels for Rene and his family with what they're going through right now," said Aime. "It's one of the hazards of the job." Douglas is a native of Panama City, Panama, and came to the United States in 1983. He won the 1996 Belmont Stakes on Editor's Note for trainer D. Wayne Lukas, and at various times has ridden regularly in New York, California, and Kentucky. Douglas first came to Arlington in 2001, and immediately won the riding title here. Partnering with agent Dennis Cooper, who has been in regular contact with Natalie Douglas, Razo, and Dr. Gordon, Douglas was leading rider four years in a row before summering in California in 2006. He quickly regained his position atop the Arlington jockey colony upon returning to Chicago during the summers of 2007 and 2008. Born to Be, who shipped in from Woodbine for trainer Eric Coatrieux, also was badly injured. She was taken by horse ambulance to Arlington's detention barn, and had to be euthanized later Sunday night. Doreen Razo's husband, Eddie Razo, is Douglas's best friend in the Arlington jockeys' room. "It's just been a hard day," Eddie Razo said near the end of Arlington's racing program Sunday. "I've been with guys before that have gotten killed. But Rene, I've known him for 20 years. Things happen like that all the time. But this was so quick, Rene never had a chance."