Only a week after Shannon Cropper first noticed Temple University's cherry-and-white "T" on a ReadyCare Center at the Pavilion in Jenkintown, he found himself sitting in an examination room there with his 9-year-old daughter, Kennedy, who had tumbled off her bicycle and twisted her ankle.

"I'm having a hard time walking on it," Kennedy said as she rested the injured joint on her father's lap.

Just 45 minutes after entering the ReadyCare's bright waiting room, Kennedy had had her vital signs taken, been examined by a doctor, and had her swollen ankle X-rayed. Father and daughter were now waiting for a radiologist a few miles down the road at Temple University Hospital to read the film.

"It's well-organized," Cropper said of ReadyCare, one of a growing number of urgent-care centers set up by hospitals like Temple. "My first impression is that this is amazing."

Cropper and Kennedy were getting a peek at what might be the new medical care paradigm. The era of the all-in-one primary-care physician may be coming to a close, replaced by a more cost-effective and time-efficient system that matches a patient's need with the level of care. And urgent care, where patients can be seen without an appointment and treated for everything from flu symptoms to a broken bone, is playing a pivotal role.

"The very old [health care] model . . . is that you have an internist who has an outpatient office who you saw when you got sick, and if you went into the hospital, he rounded on you in the morning and checked up on you in the evening and followed your care through the hospital," said Ari Friedman, an M.D. amd a Ph.D. candidate in health management at the University of Pennsylvania's Wharton School. "That doesn't exist so much anymore."

No one can say for sure what will supplant the traditional model. But what seems to be emerging are distinct layers of care. For example, emergency rooms would treat major traumas and life-threatening situations, while urgent-care centers and retail clinics - those in pharmacies and other stores - would see patients for acute illnesses, sprains, strains, and similar ailments.

The primary-care physician, responsible for the patient's overall well-being, including preventive and long-term chronic issues such as heart disease and diabetes, would be apprised via electronic records.

"People are trying lots of different things, lots of different business models," Friedman said. "We'll see what happens and what the consequences are."

The urgent-care concept - some call it "doc-in-a-box" - has been around since the 1970s. But it wasn't until 2008 that the idea caught fire, just as the Affordable Care Act was being debated in Congress. Two-thirds of today's 8,700 urgent centers have opened within the last five years, Friedman said.

"The industry has been adding fairly consistently for the last several years about 500 centers a year," said Alan Ayers, practice management content adviser for the Urgent Care Association of America. "It is one of the fastest-growing segments of medicine."

Urgent-care centers, like Jenkintown ReadyCare, are usually staffed by a doctor and a nurse who treat such ailments as fevers, upper respiratory infections, sprains, lacerations, back pain, and broken bones.

The centers, which have X-ray machines and labs on-site to perform blood and urine tests, offer shorter waiting times than a primary-care office or ER, along with evening, weekend, and holiday hours. Urgent care costs about the same as a primary-care visit and far less than a trip to the ER.

Philadelphia has at least 25 urgent-care centers within a 50-mile radius. Aria Health opened one in Torresdale last month and plans a second one in Levittown.

Jenkintown's ReadyCare, which opened in April, is Temple's third center and its first in the suburbs. The other two are in Port Richmond and the Northeast. A fourth is set to open in July in Fort Washington.

"We made a decision as a health-care system that we want to be a regional provider of healthcare," said Marc P. Hurowitz, chief executive officer of Temple Physicians. "I do believe that urgent care will be the future."

Hurowitz isn't alone in that belief. Hospitals, insurers and even private-equity funds are investing in urgent-care centers, although half are owned by individual doctors. But urgent-care centers are expensive to run. So why are so many groups eager to buy into the business?

The short answer is the Affordable Care Act. Next year, about 30 million people will get insurance and flood the health system. And most of them lack a primary-care doctor.

"There is going to be a greater demand for health-care services," Ayers said. "That is going to stress the already limited services that we have. Those things should bode well for urgent care."

It also bodes well for small retail clinics. Usually set in high-traffic outlets with pharmacies like CVS, retail clinics have grown from 150 outlets in 2006 to 1,450 today, according to the Convenient Care Association. That includes 19 MinuteClinics and TakeCare Clinics in the Philadelphia area. Nurse practitioners and physician assistants mostly work the clinics and treat chronic disease, give immunizations, offer wellness and preventive services, and do minor procedures.

Primary-care physicians have responded to the changing need by increasing office hours and offering more same-day appointments, said Jeff Cain, president of the 110,000 member American Academy of Family Physicians.

"Americans may think, 'Oh gosh, I can't get into my doc's office,' " Cain said. But "you will find out that in the last 10 years, three-quarters of all family doctors now have same-day appointments. Half of all family doctors have weekend or evening hours, because it is very important to be patient-centered."

While Cain does see a "well-defined" role for clinics, he cites studies showing that for overall care, patients are better off having a long-term relationship with a doctor.

Ayers agreed, saying that urgent-care providers seek to complement the family physician.

"Where it works out well is when the urgent-care provider communicates with the primary-care doctor and sends the chart, with the patient's permission, to the family provider and kind of keeps them in the loop," Ayers said. "By working together, I think there is kind of an ecosystem where all these providers can coexist."

But Cain is concerned that urgent-care centers may expand into more complex and chronic care.

"We feel that is not the best thing for people to get a piece of your health care here and a piece there," he said. "An urgent-care center is a little like fast food in that all Americans will occasionally have a fast-food meal, but we wouldn't want you to base your diet on that."

Kennedy's X-ray results come back with good news.

"All right, it's a normal X-ray," physician Horace Barsh announced as he walked into the examination room. "It's just a matter of staying off of it for three or four days."

"Yeah," beamed Kennedy, as she high-fived the doctor. "I like it here better. It's faster."

Bob Calandra can be reached at 215-836-0101 or rotoca@comcast.net.