Detection of the changes in coronal scoliotic curve profile from upright sitting to forward-bending position by ultrasound in patients with Adolescent idiopathic scoliosis (AIS)

W. W. Jiang, C. L.K. Cheng, J. P.Y. Cheung, D. Samartzis, H. Begovic, M. K.T. To, Yongping Zheng

Research output: Journal article publicationJournal articleAcademic researchpeer-review


During forward bending (Adam's test), spine shifts to either side and changes its pattern. Such a dynamic 3D change is difficult to be quantified with conventional X-ray imaging techniques due to exposure to ionized irradiation. For this reason, 3D ultrasound imaging was developed. Using a handheld ultrasound probe, we aimed to investigate measurement accuracy, detect dynamic changes during forward-bending, classify the curvatures and compare differences. Material and method: A total of 72 AIS patients, age: 15.3 ± 1.9 yrs, BMI: 18.0 ± 2.4 kg/m2were recruited. All patients received standing AP X-ray radiograph (EOS) for comparison with 3D ultrasound scanning (Scolioscan). Trunk rotation (ATR) was measured by scoliometer. Scanning was performed between L5 and C7 by a handheld probe in upright-sitting and forward-bending positions. 3D-image was reconstructed based on 2D-images, and spinal processes were used to form a spinal process angle (SPA), representing coronal plane changes. Results: Reliability of SPA measurement was found very good (ICC: 0.86) in both sitting and forward-bending positions. The SPA significantly decreased from 15.1 ± 6.3° to 11.8 ± 6.9°(P < 0.001) by forward-bending. Very low correlation was found between SPA change and ATR (r = 0.064, P = 0.62) and Cobb's angle (r = 0.17, P = 0.09). The C-shape curve remained C (n = 20), while S-shape curve changed into C (n = 17) and rest of patients (n = 35) retained S-shape during forward-bending. Conclusion: Using ultrasound to construct a 3D image of the spine revealed significant changes in the coronal plane during forward-bending, where the biggest amount of flexibility, presented by a difference between two positions, happened in S-shape curvature. C-shape displayed the smallest change. This ultrasound technique, as a reliable measurement, is expected to facilitate understanding of the functionality and/or flexibility of the scoliotic curve. Hence ultrasound provided frequent scanning can potentially bypass X-ray imaging, help to follow the progress with frequent scanning and redesign the treatment accordingly.
Original languageEnglish
JournalAnnals of Physical and Rehabilitation Medicine
Publication statusAccepted/In press - 1 Jan 2018


  • Forward-bending
  • Scoliosis
  • Ultrasound imaging

ASJC Scopus subject areas

  • Orthopedics and Sports Medicine
  • Rehabilitation

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