His comrades carried him back to base camp, but there was hardly any medical care there. It took 25 days before he received proper treatment, during which time he developed tetanus on one side of his body. Finally he was put on a flight to the Kenyan border, his life saved when he was handed over to a Red Cross health team. Now, a decade later, he lives in a Juba refugee camp, having suffered further troubles in the whirlwind of conflict that has engulfed the struggling new nation of South Sudan.

During one outbreak of violence he was rounded up with other Nuer—the country’s second-largest ethnic group—and taken to an army barracks. His life was only spared when he was dismissed as “useless” because of his disability. Today he plays wheelchair basketball for his country, although he relies on a prosthetic lower leg to struggle his way round the muddy, sprawling camp that entails long walks to reach the most basic services. It can be difficult to get to training. But at least his hands are free to carry things such as food and water, unlike those on crutches.

One woman, age 34, who caught polio as a child and today works as a restaurant supervisor in the capital, Juba, explained what it was like growing up reliant on bamboo sticks to haul herself around with a bad leg. She would get up much earlier than her siblings, since it took an hour to get to the classroom and they could rush there much quicker. “It was hard to go with my exercise book to school unless I tie it on my back like a baby,” she said. And it limited her use of her arms too. “When two hands are using the bamboos you are not able to do domestic work in the house.”

Stories of lives devastated by conflict or disease are all too common across low-income countries. Lack of an arm or leg can be tough anywhere, but for people in poorer parts of the planet, with so much less support and more rickety infrastructure, it is especially challenging. Some are victims of conflict, others were born with congenital conditions. Many more are injured on roads, the casualty toll soaring in low-income nations even as it plummets in wealthier ones. Every minute, 20 people are seriously injured worldwide in road crashes. In Kenya, half the patients on surgical wards have road injuries.

The World Health Organization (WHO) estimates there are about 30 million people like Nhial and Lam who require prosthetic limbs, braces, or other mobility devices. These can be simple to make and inexpensive. As one veteran prosthetist told me, his specialism is among the most instantly gratifying areas of medicine. “A patient comes in on Monday on crutches that leave them unable to carry anything. By Wednesday they are walking on a new leg and on Friday they leave with their life transformed.”

Yet more than eight in 10 of those people needing mobility devices do not have them. They take a lot of work and expertise to produce and fit, and the WHO says there is a shortage of 40,000 trained prosthetists in poorer countries. There is also the time and cost to patients, who may have to travel long distances for treatment that can take five days—to assess need, produce a prosthesis and fit it to the residual limb. The result is that unglamorous items such as braces and artificial limbs are among the most-needed devices to assist lives. Yet, as in so many other areas, technology may be hurtling to the rescue, this time in the shape of 3-D printing.