Here are a couple of slightly sick urban legends about people in wheelchairs. One is American, and one is Irish; each has a funny twist. Neither is very likely to be true, although they are usually told that way.

I first encountered "The Runaway Patient" in the journal Indiana Folklore, in an article by Anne Phipps, an associate professor at the Indiana School of Nursing. She collected variations of the legend from personnel at five Veterans Administration and university hospitals in the Midwest.An elderly patient, partially paralyzed and unable to speak, was put into a wheelchair and wheeled onto an elevator to go to a therapy session on another floor of the building. But nobody in therapy had been notified that the patient was coming. And no one riding on the elevator questioned whether the patient knew where he was going or was capable of getting there on his own.

Supposedly, the wheelchair-bound patient simply rode up and down in the elevator until he was missed back in the ward and a staff member there figured out what happened and went to rescue him.

By then, so the story goes, the patient was dead, or else weak and severely dehydrated from riding unattended for so long.

I encountered this legend again in 1983 when I read an article in TV Guide about the writers of the TV series "M*A*S*H," who were then preparing the spinoff series "AfterM*A*SH*," which was set in a VA hospital.

The article explained that the writers had "collected material on VA hospitals in the '50s." And the show's star, Harry Morgan (who played Col. Potter), had contributed a story that he had heard from his next-door neighbor, a physician.

Sure enough, it was "The Runaway Patient."

In Morgan's version, the patient was a stroke victim and was being sent from his sixth-floor room to a therapy session in the basement of the hospital. He rode on the elevator for three days, unable to summon help, before rescuers arrived.

I don't know whether "The Runaway Patient" was ever incorporated into an episode of "AfterM*A*S*H," but it certainly is "M*A*S*H"-style humor.

The wheelchair legend from Ireland, which I call "Miracle at Lourdes," was told to me by a Dublin folklorist, who collected it from a woman who had heard it from her parish priest.

There was an Irish Catholic woman, the priest said, who, because of her poor health, traveled to France in order to visit the famous shrine to the Blessed Virgin Mary at Lourdes. The spring water there is renowned for its miraculous healing powers.

The woman felt very tired during the long wait at the grotto for the blessing of the sick to begin. And since there happened to be an empty wheelchair among the crowds of pilgrims, she sat down in it for a rest.

As a priest finally approached to give the healing blessing, the woman stood up from the chair to meet him. "And immediately, when the people saw her rising," the Irish priest said, "everybody started to claim that it was a miracle.

"And the crowds gathered around her, and started to push and to shove, and wanted to touch her, and feel her, and all this.

"And with all this commotion, and all the pushing and shoving, she fell and broke her hip. So the poor woman came home from Lourdes with a broken leg!"

These two stories give the term "sick humor" a new connotation.

(C) 1988 United Feature Syndicate Inc.