Judy R., 67, a former social therapist, said she began to slip into isolation shortly after a back injury forced her into early retirement nine years ago. Her physical disability, compounded by failing eyesight and a hip injury a few years ago, turned her into a recluse, the Silver Spring resident said.

"It's hard when you can't get around," said the woman, who asked not to be further identified. "I don't like asking for help . . . . I was a very independent person."

Last week, at the urging of a social worker who comes to visit her on occasion, Judy R. came out of her shell to attend a conference, one that let her know she is not really alone. Held at the Armory Building in Silver Spring, and sponsored by Family and Nursing Care Inc., a private social service organization, it was all about the problems of the isolated elderly, a subject still relatively unexplored.

About 200 elderly people and social service professionals in the field heard gerontologists discuss the growing concerns of doctors, nurses and adult-care facility operators. Old persons who for physical, psychological or social reasons have cut themselves off from society are labeled "isolated," but are little understood today, some speakers said.

"The concept of isolation is in the same place where senility was 10 to 15 years ago," said Eloise Rathbone-McCuan, an associate professor of sociology at the University of Vermont, and coauthor of a book on the subject.

While there are no current figures on how many isolated old people there are here or elsewhere in the country, health experts said they believe that the number is growing as the percentage of older Americans increases.

"There is no way to measure the numbers," said Lynn Chaitovitz, chief planner for the division of elder affairs in Montgomery County, where 50,905 people -- including 13,950 who live alone -- were over 65 in 1980. Old people accounted for about a 10th of the county's population, one of the highest percentages in the area.

While some old people choose to become reclusive, in its more severe form isolation can lead to physical degeneration and psychological instability, said heads of social service agencies in the region and specialists in the problems of aging.

Some factors that can lead elders to withdraw from society are physical disabilities, depression, alcoholism, illness, poor vision or hearing, death of a spouse, or a degenerative loss of memory, the speakers said. A loss of social roles or feelings of worthlessness also are contributing factors, they noted.

While some elderly persons shun assistance, many are unaware of the services available for them, or think they cannot afford adult care, health officials said. Social service organizations said they are working toward building networks to find the elderly and let more people know what kind of care is available, such as recreational programs of the county and private agencies. Other services provide nurses to help the elderly and aides to do chores such as laundry, shopping and preparing meals. Some also provide companions.

After the conference, Judy R. said she learned that she must take the lead to bring herself out of isolation. She said she wants to find out what organizations offer "friendly visitor" programs so she can have someone to talk to and also will look into joining social organizations for the old.

"I have to reach out," she said. "I get the feeling I was just sitting around feeling sorry for myself."