(CNN) -- Cyclist Lance Armstrong said Thursday the surgery to repair his broken collarbone proved to be more complex than doctors originally anticipated and that he will take his recovery "day by day."
Cyclist Lance Armstrong needed 12 screws to repair his broken collarbone.
"I thought everything went very smooth," he said in a video to his supporters about Wednesday's three-hour operation.
Doctors in Spain, where Armstrong injured himself Monday when he fell during a race, initially thought he had suffered a simple fracture. However, additional X-rays and CT scans in Austin, Texas, where he lives, proved otherwise.
"They realized that the collarbone is actually in quite a few pieces," said the 37-year-old cyclist, who pointed to an X-ray of a 4- to 5-inch steel plate held in place by a dozen 1-inch screws, intended to stabilize it.
"That should keep things together," he said. "Ultimately, that will have to come out, but for now, it's necessary." Watch how Armstrong "tweets" from hospital »
Armstrong said he felt "very lucky, very blessed" that, in almost 20 years of professional cycling, he has rarely crashed.
"We don't know how my recovery will go, we'll just take it day by day and ultimately get back on the bike and try to sort things out."
Armstrong's remarks came a day after his surgeon, Dr. Douglas Elenz, told reporters that the cyclist will require two to three months of healing.
The four breaks "made treatment more challenging, but we're confident that the treatment performed today is going to be successful," Elenz said.
During the next week, Armstrong "will need to take it easy" to ensure the wound does not become infected, the doctor said.
After his wound has healed, Armstrong will begin using an exercise bike to train his lower body, "but we won't let him do a whole lot with his upper extremities," Elenz said. "After several weeks, we can take his training to the street, but we will need to take that day by day and week by week."
He said that, over the longer term, he will be looking for evidence that Armstrong is laying down new bone, that the plate is stable, that the athlete's arm is strong and that his motion is fluid.
Armstrong, riding for Team Astana, crashed about 10 miles (16 kilometers) from the end of the first stage of the five-day Vuelta Ciclista a Castilla y Leon race. Watch Armstrong's crash »
Armstrong announced last year that he was returning to competitive biking and would use the Spanish race as a warm-up for the Tour de France, which he won seven times before retiring in 2005.
He also had planned to race May 9-31 in the Giro d'Italia, one of Europe's most prestigious and grueling stage races.
This would have been the second comeback of his career. His first came in 1998, two years after he was diagnosed with advanced testicular cancer that had spread to his lungs and brain. Doctors gave him a less than 50 percent chance of survival.
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