Are there deviations in the thickness of abdominal muscles at rest in individuals with adolescent idiopathic scoliosis (AIS)? Are there deviations in abdominal muscular activity in people with AIS during the active straight leg raise (ASLR) test?Summary of Background Data:
Ultrasound imaging can be used to assess the lateral abdominal muscle. Some authors suggest that scoliosis develops through a weakness or improper functioning of the abdominal muscles that cannot provide adequate support to the spinal segments. However, the literature lacks studies on the functioning of the abdominal muscles in individuals with spinal deviations. This study focuses on the evaluation of the thickness of the external oblique (EO), internal oblique (IO), and transversus abdominalis (TrA) muscles of individuals with AIS.Materials and Methods:
Seventy-one healthy adolescents and 71 patients with AIS, all aged 10–16 years, were studied. The thickness of the muscles at rest was measured at the end of normal exhalation in millimeters. Muscular activity during the ASLR test was measured in the final position, and the standards were normalized with the thickness produced at rest. Muscular activity during the ASLR test was represented as a percentage change in the muscle thickness.Results:
The AIS group demonstrated a smaller resting thickness of all tested muscles of both sides (P<0.01). All the muscles on the right side of the body showed higher activity in the AIS group during the ASLR test (P<0.01).Conclusions:
Patients with AIS had thinner EO, IO, and TrA at rest in the supine position. During the ASLR test, the AIS patients displayed higher activity of the EO, IO, and TrA muscles on the right side.