Over 5 million primary and middle school students in China suffer from curved spines, a figure that is increasing by 300,000 new cases each year, according to an epidemiological survey conducted by the Chinese Preventative Medicine Association.

A survey covering 370,000 middle school students in Shanghai also detected the incidence of curved spines is 5.4 percent, or about 1 in 20.

Curvature of the spine is a skeletal disease that can cause deformed spines and thoracic cage, bad posture and other physical symptoms like waist pain, nerve damage and adverse impact on the heart, lungs and digestive system, according to experts.

"Puberty is the peak time for curved spines, so we encourage minors to undergo screenings each year," said Dr Chen Jianbin from Shanghai Carespine Rehabilitation Center. "Most our patients are minors between 10 and 16 years old, the majority of whom are girls.

Experts say parents must heighten awareness and remind their children to maintain good posture, as well as take them for regular screenings and early diagnosis and rehabilitation if a curved spine is detected.

"Bones grow quickly during puberty. If not treated in a timely manner, curves become serious," Chen said.

A curve within 10 degrees can be corrected through proper posture and physical exercises.

Those with curves of 20 or 30 degrees require professional training, braces and rehabilitation, while people with higher-degree curves should have surgery, experts said.

"So early detection and intervention are very important," said Chen, whose center has established a foundation to help poor families with children who have curved spines.

Children doing rehabilitation exercises under the guidance of therapists.

A curve within 10 degrees can be corrected through proper posture and physical exercises.