In a recent study, researchers assessed how much time should pass before taking an x-ray after a patient with moderate adolescent idiopathic scoliosis (AIS) has donned and doffed his or her spinal orthosis. They concluded that x-rays of patients with AIS should not be taken within two hours of donning or doffing the spinal orthosis, as it may not show the maximum effect, likely due to the low-stiff and viscoelastic properties of the spine. The results were published May 22, online before print, in the journal Spine.
For the study, nine female patients with AIS were divided into two groups, the don-orthosis group and the doff-orthosis group, and researchers measured the time it took to reach maximum correction and the time it took to return to pretreatment curvature. Spinal flexibility, estimated from supine radiographs, and body mass index (BMI) were also collected and analyzed. To avoid excessive x-ray radiation exposure, participants were tested using a validated method of estimating Cobb angle using radiation-free clinical ultrasound (CUS). The CUS was applied every 30 minutes up to 180 minutes.
The researchers found no immediate change in the Cobb angles. A change of more than 5 degrees was observed in both groups after 30 minutes and maximum change was found at/after 120 minutes. In the doff-orthosis group, the subject with the lowest BMI took the longest time to increase more than 5 degrees. In the don-orthosis group, the subject with the highest BMI took the longest time to achieve curve correction.
