The lawyer for a 12-year-old refugee boy who suffered a broken arm at the Nauru detention centre last year says his client needs urgent medical treatment.

Erfan, who lived in the Nauru community outside of the detention centre, after his family were granted refugee status, underwent surgery to insert plates into his arm after he fell off his bike in May 2015.

But his lawyer George Newhouse said he was given no post-operative care and had now lost some movement in his wrist and fingers.

"Unless action is taken urgently, this boy may never be able to use his hand and arm properly again," he said.

"That is the most astounding situation, when all we have is a fracture."

Mr Newhouse said Immigration Minister Peter Dutton urgently needed to intervene, to give Erfan and his family some comfort.

"They weren't asking to come to Australia for treatment," he said.

"They were in Papua New Guinea, in Port Moresby, all they wanted was a doctor to care for them in Port Moresby.

"That was the reason they were taken there, and they didn't get any treatment after months and months of waiting."

In a video message to Mr Newhouse, Erfan said he just wanted his family to be treated.

"We don't want anything, we just want treatment and we want my family to be OK — every one of them," he said.

"My mum needed treatment for her breast ... they need to take off the cyst in the breast.

"My sister, she needed treatment. She will have to be in a good place."

Department confident boy's medical care 'appropriate'

In June last year Erfan's mother said immigration officials had told her Australia had agreed to send doctors to provide treatment, but she did not want the surgery to be carried out at Nauru Hospital because it was poorly equipped and had unsanitary conditions.

"They will send a team from Australia, but I repeat: I was made angry because I know Nauru Hospital is not qualified to do operation on my son's arm," she said.

The boy's lawyer says he has received no follow-up care. ( Refugee Action Coalition. )

At the time, Mr Dutton told 2GB radio there were medical services available in Nauru.

"The Nauruan Government obviously has the system up there to provide people with support that need it when it comes to medical attention," he said.

A Department of Immigration and Border Protection spokesperson said it was aware of Erfan's medical history and sent a surgical team to Nauru to operate on his arm last year.

"The boy and his family were transferred to PNG in April of this year, where the boy received further post-operative care. The additional members of this family also received medical treatment while in PNG," a spokesperson said.

"The Department is confident that the medical care the boy has received, and the ongoing medical assessment and treatment he is receiving, is appropriate.

They said post-operative care had been in place since Erfan undertook surgery.

"As the family had completed medical treatment in PNG they no longer had any legal basis to remain in PNG, as determined by the Government of PNG," a spokesperson said.

"The return of refugees from PNG to Nauru is a matter for the PNG and Nauruan Governments."