McDonald’s Corp. today said U.S. comparable-store sales rose for the 10th consecutive month in November, as the world’s biggest restaurant chain received a boost from a nationwide rollout of its McRib pork sandwich.

In early November, McDonald’s made the McRib available at restaurants across the U.S. for the first time since 1994 and promoted the sandwich with ads on major television networks. Previously, the McRib, a pressed pork patty covered with barbeque sauce and onions, was available in only a few selected markets.

The McRib “helped drive sales in November,” said McDonald’s spokeswoman Lizzie Roscoe said. “We were pleased with its performance.”

Sales at U.S. stores open at least 13 months increased 4.9 percent in November compared with the same month in 2009, Oak Brook, Ill.-based McDonald’s said in a report today.

For U.S. pork producers, any demand boost from the Golden Arches probably will be short lived. While McDonald’s is one of the country’s biggest buyers of beef that it uses for the Big Mac and about 20 other sandwiches, the McRib is the only non-breakfast pork item on the company’s menu.

The McRib promotion ended Dec. 5, and McDonald’s wouldn’t say whether it has plans to make the sandwich available nationwide again any time soon.

It’s unusual for McDonald’s to single out a specific menu item in monthly sales reports, said R.J. Hottovy, an analyst in Chicago with Morningstar, Inc. Promoting a sandwich like the McRib “creates buzz” and “makes sense seasonally,” Hottovy said, but longer-term likely isn’t going to become a core menu item, he said.

The McRib is “kind of a limited-time offering to bring traffic into the stores,” Hottovy said. “But it’s way too early to say that this would be something on the menu full-time. It’s not something they’re prepped for over a long time.”

Roscoe wouldn’t say where McDonald’s buys its pork or elaborate on the company’s plans for the McRib.

The McRib is “one of those specialty products that has a big following that McDonald’s promotes occasionally,” Roscoe said. It’s “a popular item,” she added. “There are some fanatics out there.”

McDonald’s launched the McRib nationally in 1982 and dropped it a few years later, and the sandwich has been on and off the company’s menu since then. The McRib developed a “cult following,” according to media reports, while also drawing ire of some health experts.

“Nutritionists and other health experts recoil from the McRib as they do other fast food, seeing it as yet another threat to the nation's expanding waistline,” Sharon Bernstein of the Los Angeles Times wrote in a Nov. 2 article. “Some epicureans swear it tastes like rubber and complain that no actual ribs are included.”

McDonald’s November sales were also helped by newer items, such as specialty coffees and “everyday value throughout the menu,” the company said today. The company has held up better than many other restaurant chains as the economy struggles and consumers seek out cheaper dining options.

McDonald’s had 32,478 restaurants in 117 countries at the end of last year, including about 14,000 in the U.S.

By Bruce Blythe, Business Editor