Morphological changes of the lateral abdominal muscles in adolescent soccer players with low back pain: A prospective cohort study.

BACKGROUND: Most papers examining the lateral abdominal muscles (LAMs) and low back pain (LBP) are cross-sectional, with groups of participants being divided into a control and an LBP group. We hypothesized that morphological measurements of the LAMs in adolescent soccer players may predict future LBP incidence. The aim of this study was to examine the associations between the morphology of LAMs and LBP incidence rate among adolescent soccer players. METHODS: Ninety-seven adolescent male soccer players with no LBP at baseline were recruited into the prospective cohort study. The thickness of the LAMs was measured at baseline by ultrasound imaging in a supine rest position. Nine cases of LBP occurred during the follow-up 6-month observation. RESULTS: An obliquus internus (OI) asymmetry was related to increasing LBP risk (odds ratio = 19.99; 95%CI: 2.4-167.9). Spearman correlation also showed a linear relationship between OI asymmetry value and duration of LBP (R = 0.75, p = 0.02). An OI side-to-side difference greater than 1.25 mm suggests possible LBP incidence in the 6-month observation among adolescent soccer players. CONCLUSION: The morphological changes of the OI may be related to LBP's incidence in adolescent soccer players. The presence of OI asymmetry increases the odds of LBP by at least 2.4 times. Hypertrophy of the OI on one side of the body may contribute to trunk muscle imbalance.

Anatomical and functional relationships between external abdominal oblique muscle and posterior layer of thoracolumbar fascia.

The abdominal muscles are important for the stability of the lumbar region through the thoracolumbar fascia (TLF). However, there is not full agreement regarding the posterior transversal continuity of the external abdominal oblique muscle (EO) with the TLF. To clarify this point, 10 cadavers and computed tomography (CT) images from 27 subjects were used to evaluate the transversal continuity of the TLF with the abdominal muscles. The width of the fascial continuity of the EO with the posterior layer of TLF along the posterior border of the EO was also measured (40.70 ±3.92 mm). The epimysial fascia of the EO was in direct continuity with the posterior layer of TLF in eight cadavers and 23 CT images, whereas in two cadavers and four CT images, the epimysial fascia of the EO first fused with the fascia covering the latissimus dorsi, and then, both fasciae were in continuity with the posterior layer of TLF. Therefore, the transversal fascial continuity of the EO could explain the transmission of tension from the EO to the posterior layer of TLF and its importance in maintaining the stability of the lumbar spine through a hydraulic effect. Regarding fascial continuity in the trunk, and taking the EO into consideration, the TLF is formed by the fascia of all the abdominal muscles as the rectus sheath. In this manner, myofascial continuity between the TLF and the abdominal muscles is achieved through the aponeurosis and fascia, which ensures synchronization between the erector spinae and the rectus abdominis. Clin. Anat. 31:1092-1098, 2018. © 2018 Wiley Periodicals, Inc.

Reliability of the lateral abdominal muscle thickness measurements in idiopathic scoliosis patients.

BACKGROUND: To date, the reliability of ultrasound imaging (US) measures of the abdominal muscle thickness in idiopathic scoliosis (IS) patients during early stages of adolescence has not been confirmed. OBJECTIVE: To assess the intra-rater reliability of US measures of the thickness of the external oblique (EO), internal oblique (IO), and transversus abdominis (TrA) on convex and concave body sides in adolescents with IS. DESIGN: One-way repeated-measures analysis of variance (ANOVA) and reliability study. METHODS: Fifteen patients diagnosed IS were included between the ages of 9 and 14 years. Three repeated US measurements were recorded in the supine resting position over 2 sessions, 24 h apart. RESULTS: By assessing the mean value from the first two measurements (ICC3,2), the reliability was between .76 and .95 for all examined muscles on the convex and concave sides. The reliability for the mean values from three measurements (ICC3,3) was between .81 and .96. The smallest detectable difference values for single measurements were twice as high on the convex side than on the concave side for all examined abdominal muscles. CONCLUSION: US measurements of the thickness of the EO, IO, and TrA muscles in supine rest position in adolescent IS patients are reliable. In order to increase measurement reliability, and due to variability in reliability between concave and convex body side, we recommend using the mean of three consecutive measurements of the EO, IO, and TrA muscles for adolescents with IS.