An African teen is doing well after undergoing surgery to treat crippling conditions in his arms. 

Mamadou of Guinea received help from a Christian organisation in the UK to lessen the severity of a condition locals nicknamed "devil hands."

The 17-year-old was born with deformed arms that prevented him from lowering them below his head. 

"I was born with my elbows bent inwards and my wrists bent downwards. I couldn't straighten my arms, but I learned how to cope," Mamadou told the Daily Mirror. 

His parents sent him to beg for money in Conakry, 300 miles from his home.

One day, a Mercy Ships boat called The Africa Mercy docked at Conakry. The ship is a travelling hospital, providing free medical treatment for disadvantaged persons across the world. 

Mamadou approached the ship and asked for help. 

"I told the nurse I could do so much more than people thought," he recounted. 

Mercy Ships volunteer surgeon Dr Tertius Venter determined that the teen's left arm could be fixed. 

Mamadou had only four fingers on each hand, but Dr Venter moved one of the right fingers to the left hand to create a thumb. The right arm was lowered, although it still curves inward. 

"If they had tried to fix my right arm, it would have only have made things worse for me," Mamadou explained. "I was just happy they could do anything at all."

The left arm is expected to be fully functional. Mamadou called the doctors his "guardian angels," and looks forward to having a better quality of life. 

"I don't scare people away anymore," he said. "I can support my family properly and without shame. One day, I will own my own stall and maybe have a family of my own."