Riley to Undergo Surgery to Correct Pinched Nerves : Illness: Spinal operation is intended to relieve severe pain in legs of Board of Supervisors chairman. He is expected to be in Hoag Hospital from three to six days.

Orange County Supervisor Thomas F. Riley is scheduled to undergo spinal surgery today at Hoag Hospital to relieve the severe leg pain that his doctors attribute to pinched nerves in his lower back.

The 81-year-old politician returned to the Newport Beach hospital Wednesday afternoon, just two months after he was admitted for treatment of a foot infection, said Christie McDaniel, his chief of staff.

The three-hour surgery will begin at 7:30 a.m., and McDaniel said an early estimate of the hospital recovery was three to six days.

McDaniel said Wednesday that Riley has weathered agony in recent months because of the pinched nerves, which have sporadically sent sharp jolts of pain through his legs. In recent weeks, the pain’s frequency began to increase, most recently striking when he put even the slightest weight on his legs.

“He didn’t really notice it too much because with his foot problem, he wasn’t using his legs anyway, he was in the wheelchair,” McDaniel said. “But then as he started recovering and using his legs more, he started complaining more and more.”

Riley underwent magnetic resonance imaging last week, a scan that pinpointed nerves in his lower back as the likely culprit behind the discomfort, McDaniel said.

Riley’s wife, Emma Jane Riley, said Wednesday: “There is certainly an element of risk and he’s aware of that. We have a fine neurologist, and we have the utmost confidence in our doctors.”

Riley, a retired Marine Corps general, has represented the 5th District on the board since his 1974 appointment by then-Gov. Ronald Reagan. Riley, now serving as chairman of the board, has announced that he will retire when his term expires next year.

In recent years, Riley has weathered a series of maladies.

The infection of his left foot, an inflammation of the soft tissue called cellulitis, left him hobbled for more than a month and, during December, undergoing antibiotic and whirlpool bath treatments.

He was hospitalized for several days just before Christmas because doctors feared the infection could spread to his bloodstream.

Riley was checked into Hoag twice in 1992 for observation because of concerns linked to his diabetic condition. During one of those stays, doctors discovered that he suffered from bronchitis. For years he has had emphysema and asthma, and in 1991 he underwent quadruple bypass heart surgery.