Scientists are hoping to use an 'elastic' metal usually used to make spectacle frames to help patients with severe curvature of the spine. If the technology, planned for clinical trial early next year, is successful, Hong Kong will become the first place in the world to use the method to cure scoliosis, a bone deformity that affects about 3 per cent of the population. The ground-breaking idea was born eight years ago when the University of Hong Kong team became aware of the 'memory' characteristic of nickel-titanium alloys - metals which become soft and super-elastic at low temperatures but gradually return to a preset shape when the temperature rises. Orthopaedic professor Kenneth Cheung Man-chee, a member of the research team, said the alloys were usually used for spectacle frames and water valves and their use was very limited in medicine, mainly in heart surgery. Dr Cheung said the alloys' properties made them ideal for rectifying scoliosis. The team would fit the deformed spine with a 'soft' nickel-titanium frame. The frame would then take advantage of the metal's memory to realign the patient's spine. The patient's body heat would be enough to raise the metal's temperature to make it return to a preset shape, in the process reshaping the deformed spine. Dr Cheung said this would be more effective than conventional surgery, which uses ordinary titanium alloys that don't have the memory function. 'Without the memory function and super-elastic characters, in the metal used in the conventional method the correction is usually no more than 80 per cent. The conventional surgery may also bring injuries and cause spinal fractures if too much force has been used,' he said. Dr Cheung said that the team planned to further extend the use of the special metal in the medical field. Fellow team member Kelvin Yeung Wai-kwok said it was important to rectify the bone deformities before they threatened the function of major organs such as the lungs. The bone disease is believed to be linked to genetic factors as children with mothers suffering from the condition have a 37 per cent chance of developing the disease, normally before puberty. With 80 per cent of patients women, the disease is thought to be linked to hormones, Dr Cheung said.