On the crisp pre-dawn of the South Australian desert, the Royal Flying Doctor Service flight takes off along a dimly lit runway at the Port Augusta airport, bound for William Creek.

The medical team, consisting of a doctor and three specialist nurses, is attending the tiny settlement's annual bronco branding competition — an event that almost certainly would have been cancelled had the RFDS not committed to turn up.

The SA division of the RFDS flew to four similar outback events last year and will attend as many as eight events this year — a move Cheryl Boles, the Port Augusta practice manager, said came about because the communities that run the remote gymkhanas needed medical support on site for insurance purposes.

"They were in crisis because they couldn't afford the insurance payments that they needed to cover the event," Ms Boles said.

"If we could provide medical support then it brings their insurance premium down so it becomes more affordable and the event can actually go ahead," she said.

"They were looking to cancel their events in 2017, they came to us and asked if there was anything that we could do."

Bronco branding is a rough-and-tumble affair, with participants on horse-back roping a cow or steer, after which on-ground competitors tie the animal to a metal frame.

Bronco branding is a rough-and-tumble affair and there is the high risk of graziers getting hurt. ( ABC News: Prue Adams )

There are also rodeo events and something called "chute dogging", which requires two participants to wrestle a bovine to the ground with their bare hands.

Participants are tossed and trampled and dragged and there is the distinct risk of injury.

The Flying Doctor team is on hand to supply the emergency medical care, but it also gives them a chance to enquire about the health of their outback clients and dispense information and education about a range of issues from mental health to diabetes management.

Bush events are an opportunity for health education

These events also present a rich seam of blokes — traditionally the group who don't present to the doctor unless they're in a state of medical crisis.

Mandy Smallacombe, a chronic disease coordinator, approached a group of three young men with broad hats, sitting in the powdery red dust up against the cattle yards.

"We're doing a bit of men's health screening and telling you how important it is to play with your balls at least once a week," the specialist nurse says in good humour, while brandishing a pair of rubber testicles.

"That's not a problem," shoots back one of the blokes.

And so the rubber "balls" are handed around, with each man seeing if he can find the three hidden lumps.

Ms Smallacombe tells the men their wives and girlfriends should be on the look out for testicular changes too.

"Jeez, if she squeezes that hard I'll be in trouble," says one of them as his mate pinches the rubber.

Amid the slightly nervous and awkward banter there is an important message being imparted.

Nurses use rubber testicles to teach men to check their balls for lumps. ( ABC News: Prue Adams )

Testicular cancer is the second most commonly diagnosed cancer after skin cancer in men aged between 20 and 39, according to the Cancer Council.

A painful swelling or lump are the most easily detected symptoms.

"We would say we save lives in a way people don't even notice," Ms Boles said.

"Every time we give a baby an immunisation we are effectively saving that baby's life, having a yarn to a man who has a mental-health problem, struggling with the drought, we are saving that man's life," Ms Boles said.

And teaching men how to check their testicles also has the potential to save lives.

The experienced nurses can pick faces out of the crowds

The RFDS nursing team works the crowd ringside at William Creek; they know a lot of these people by names — having attended emergencies at their properties or weekly clinics in their small remote communities.

Therese McCourt, a primary care nurse, finger pricks any one who will sit still long enough — checking for blood glucose levels.

She takes blood pressures, chats to men about wearing sunscreen and dispenses a tetanus injection to a reluctant participant — a competitor who split the top of his finger.

"Some of the most important conversations happen in that environment," Ms Boles said.

"Not behind a desk at a clinic."

The data is entered and kept electronically — recorded onto a laptop on site so it can be followed up later.

Cheryl Boles (left) says many people in the bush don't notice when RFDS is saving lives. ( ABC News: Prue Adams )

"We can make contact with them by phone or letter or email and say 'you were seen at the bronco branding and do you want to follow that up, the next clinic near you is this clinic', so it has opened the door for lots of those particularly hard-to-reach men," Ms Boles said.

Martin Laverty, the RFDS chief executive, said the organisation cost $1 million a day to run.

While the Federal Government has provided $330m over the next four years, the organisation still relies on fund-raising activities.

And Mr Laverty maintains the community events the medical teams attend are vital for ongoing health prevention.

"Country folk see the doctor at only half the rate of people in the city," Mr Laverty said.

"If you have to travel great distances you are more likely to put the visit off."

"So we've worked out the best way to reach out to country communities is to visit them where they gather."

After an action packed day inside the William Creek cattle yards, and a few relatively minor accidents attended by the medicos outside the ring, the chill of early evening sets in.

The small plane sitting on the isolated outback airstrip was re-loaded with supplies before its post-dusk take-off.

The crew departed in the midnight blue of early morning and returned to the Port Augusta RFDS base in the deep dark of the night.

All in a day's work for the medical service that never sleeps.