In addition, the high cost of treatment and low insurance coverage prevent most patients from getting medical care.

Without treatment, OI adults can only grow to the height of a young child, with bowed limbs and protruding chest bones. Most of them are not able to move around without crutches or wheelchairs.

The condition also affects their hearing, teeth and blood vessels.

"It is a vicious circle," says Wang Lin, 26, an OI patient from Dalian, Liaoning province.

"Without money and treatment, we will become disabled. No schools are willing to accept a disabled child, and we have to self-study, or remain illiterate.

"When we grow up, we cannot do labor work because of our physical condition, and we cannot obtain good positions in companies because of lack of education. As a result, we earn too little for a living, not to mention to pay for treatment."

Wang Lin works as a receptionist in an advertising firm. But her other friends who suffer from the same condition are unemployed.

"Society should be more aware of the sufferings and needs of OI patients, and extend a helping hand to them," Wang Yi'ou says.