Yeung KH, Man GCW, Shi L, et al. - In 41 Chinese adolescent idiopathic scoliosis (AIS) girls with a primary right-sided thoracic curve and 23 age-matched controls, T2-weighted MR images with multi-planar reconstruction were acquired to examine and contrast any morphological variations in paraspinal muscles (PSM) between AIS patients (with severe or non-severe curves) and healthy controls. Between AIS and controls, abnormalities were discovered at the concavity of muscles. Significantly higher SI and fatty components was witnessed in AIS at MF muscles on concavity in comparison with controls. Moreover, SI at MF muscles was significantly associated with the Cobb angle. Thus, in PSM at the apex in AIS, elevated SI and fatty components are asymmetrically present. The higher intensity in PSM at concavity in AIS was exhibited, when contrasted with controls. An important linear association between abnormal muscle signal and the scoliotic curve was noted. The above characteristics are indicative of changed muscle composition in concave PSM, possibly because of prolonged compression and decreased muscle activity of PSM affected by the spinal deformity.