WASHINGTON – After walking unassisted from the back of a Los Angeles courtroom, 85-year-old Euralda Clodomar refused the hand of a deputy and climbed into the witness chair.

Let the record show, the prosecutor told jurors, she didn’t use a wheelchair. Clodomar doesn’t own a wheelchair, let alone the motorized model that was charged to Medicare at a cost of $3,840.

An equipment supplier had obtained her Medicare identification number and taken her and the taxpayers for a ride in a fast-growing new swindle that has cost the government’s main health care assistance program tens of millions of dollars.

Fifty separate investigations under way in nearly two-dozen states have identified $167 million in fraudulent power wheelchair claims, officials told The Associated Press.

“It certainly is the fastest growing scam in Medicare,” said Dara Corrigan, acting inspector general in the Department of Health and Human Services. “It’s about a wheelchair that is very expensive and about people trying to make a profit.”

The medical equipment industry has aggressively marketed its electric wheelchairs, particularly in television ads targeting senior citizens. The number of Medicare beneficiaries with at least one claim for a motorized wheelchair rose from about 55,000 in 1999 to 168,245 in the first nine months of this year.

Part of the increase can be explained by improvements that allow the wheelchairs to turn in a small radius. But an industry group, the Power Mobility Coalition, agrees that some claims result from fraud, and it is supporting the current government crackdown – called “Operation Wheeler Dealer.”

“If there is fraud, that hurts the good guys because it puts a black eye on everyone,” said Steve Azia, a lawyer for the coalition.

Medicare’s crackdown has recovered $52.5 million so far. Also, new suppliers have been banned temporarily from enrolling in the program, prosecutors have been ordered to bring cases quickly and officials are poised to stop payments. Medical personnel must certify they’ve personally seen a patient before prescribing a motorized wheelchair.

Investigators are focusing on Florida, Texas, California and Louisiana. They’re also pursuing potential fraud cases in New Jersey, Puerto Rico, New York, Pennsylvania, the District of Columbia, Alabama, South Carolina, Tennessee, Ohio, Michigan, Wisconsin, Oklahoma, Arkansas, Kansas, Montana, Idaho, Oregon and Arizona.

Investigators say the cases can include:

. Equipment company suppliers who submit phony claims.

. Doctors who take kickbacks for writing prescriptions.

. People who roam shopping malls offering free medical equipment to anyone who’ll sign up for a wheelchair.

. Conspirators who stage fake deliveries, complete with pictures of patients who pose with their power chairs for a fee.

By law, Medicare can pay 80 percent of the cost of motorized wheelchairs and the rest is often covered by other insurance companies. Some suppliers, investigators said, have charged Medicare for power wheelchairs costing $5,000 or more while providing much cheaper motorized scooters.

Clodomar and other beneficiaries who testified in the Los Angeles case helped persuade a jury to convict Goodwill Sunday Edukere after just 30 minutes of deliberations. Edukere had to return $249,000 and was sentenced to 33 months in prison.

Clodomar didn’t know a claim had been submitted until federal agents came to see if she had a power wheelchair. She convinced them the same way she convinced jurors.

“I walked from the back of the house, where my room is, to the front,” she said in an interview. “I said, ‘I don’t need one, thank God.”‘

Elizabeth Bostick, 89, of Ocala, Fla., and her late husband were approached by a saleswoman who represented medical equipment companies. The parent firm billed Medicare $15,500 for two motorized wheelchairs, a hospital bed, a pressure mattress and other equipment for the couple, who said they didn’t need any of it.

“They had too much pressure on me,” said Bostick, who was surprised when two red, motorized scooters arrived. “I was wondering how it could have come. I thought a doctor had to give you one,” she said.

Medicare’s 80 percent share for power wheelchairs grew from $22.3 million in 1995 to $663.1 million in 2002. That total already has been surpassed in the first nine months of 2003.