Abstract
BackgroundRecent reports have suggested a rotational strength weakness in rotations to the concave side in patients with idiopathic scoliosis. There have been no studies presenting normative values of female adolescent trunk rotational strength to which a comparison of female adolescents with idiopathic scoliosis could be made. The purpose of this study was to determine trunk rotational strength asymmetry in a group of female adolescents with AIS and a comparison group of healthy female adolescents without scoliosis.MethodsTwenty-six healthy adolescent females served as the healthy group (HG) (average age 14 years) and fourteen otherwise healthy adolescent females with idiopathic scoliosis served as the idiopathic scoliosis group (ISG) (average age 13.5 years, average Cobb 28°). Participant's isometric trunk rotational strength was measured in five randomly ordered trunk positions: neutral, 18° and 36° of right and left pre-rotation. Rotational strength asymmetry was compared within each group and between the two groups using several different measures.ResultsThe HG showed strength asymmetry in the 36° pre-rotated trunk positions when rotating towards the midline (p < 0.05). The ISG showed strength asymmetry when rotating towards the concavity of their primary curve from the neutral position (p < 0.05) and when rotating towards the concavity from the 18° (p < 0.05) and 36° (p < 0.05) concave pre-rotated positions. The ISG is significantly weaker than the HG when rotating away from the midline toward the concave (ISG)-left (HG) side from the concave/left pre-rotated 18° (p < 0.05) and 36° (p < 0.05) positions.ConclusionThe AIS females were found to be significantly weaker when contracting toward their main curve concavity in the neutral and concave pre-rotated positions compared to contractions toward the convexity. These weaknesses were also demonstrated when compared to the group of healthy female adolescent controls. Possible mechanisms for the strength asymmetry in ISG are discussed.
Highlights
Recent reports have suggested a rotational strength weakness in rotations to the concave side in patients with idiopathic scoliosis
Subsequent paired t-tests for healthy group (HG) revealed a significant weakness in the right 36° high force contraction (1.08 ± 0.3 Nm/Kg) compared to the left 36° high force contraction (1.18 ± 0.26 Nm/Kg) (p < 0.05)
For the idiopathic scoliosis group (ISG) there were significant weaknesses at the neutral position when rotating towards the concavity compared to rotating towards the convexity (0.77 ± 0.16 Nm/ Kg versus 0.89 ± 0.22 Nm/Kg, p < 0.05), at concave 18° side low force contraction (0.59 ± 0.19 Nm/Kg versus 0.72 ± 0.16 Nm/Kg, p < 0.05) and concave 36° low force contraction (0.50 ± 0.16 Nm/Kg versus 0.57 ± 0.16 Nm/Kg, p < 0.05)
Summary
Recent reports have suggested a rotational strength weakness in rotations to the concave side in patients with idiopathic scoliosis. The asymmetric muscle activity is suggested to be associated with increased axial rotation of the spine, which in turn is associated with Cobb angle progression [12]. Based on these findings, it seems logical that trunk strength asymmetry would be present in patients with idiopathic scoliosis. Two recent studies have examined the trunk rotational strength asymmetry in adolescents with idiopathic scoliosis [13,14] They reported that patients with idiopathic scoliosis were weak when rotating toward their curve's concave side and suggested a relation between the strength asymmetry and progression of the spinal curvature. No statistical analyses of the data and no comparison to healthy subjects were provided
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
