Spinal Flexibility Assessment on the Patients with Adolescent Idiopathic Scoliosis

Study Design. A literature review. Objective. The aim of this study was to review the contemporary methods for spinal flexibility assessment on the patients with adolescent idiopathic scoliosis (AIS). Summary of Background Data. Spinal flexibility is one of the essential parameters for clinical decisions on the patients with AIS. Various methods of spinal flexibility assessment are proposed, but which method(s) could better reveal spinal flexibility or predict treatment effect is unclear. Methods. The databases of AbleData, IBSS, Academic Search Premier, MEDLINE/PubMed, CINAHL, Recal Legacy, REHABDATA, Embase, and Web of Science were searched. The study inclusive criteria were (1) prospective cohort study; (2) investigated spinal flexibility on AIS patients; (3) published in English 1996 to 2016. Results. Totally 15 articles were included and 11 methods of spinal flexibility assessment were introduced in this review. Traction methods revealed higher spinal flexibility on the patients with severe curves (>65°) but lower spinal flexibility on the patients with moderate curves (40°-65°), comparing with lateral bending methods. Among lateral bending methods, fulcrum bending flexibility is higher on thoracic (T) curves, whereas supine with lateral bending flexibility is higher on thoracolumbar or lumbar (TL/L) curves. For predicting postoperative correction, fulcrum bending flexibility showed higher correlation with postoperative correction on moderate curves and traction flexibility showed higher correlation on severe curves, compared with supine with lateral bending method. Conclusion. Curve magnitude and location are two important parameters in selecting appropriate method for spinal flexibility assessment and treatment effect prediction. The traction method should be considered for the patients with severe curves, while the lateral bending method is suggested for the patients with moderate curves. The fulcrum bending method is recommended to assess T curve flexibility, whereas the supine with lateral bending method is for the assessment of TL/L curve flexibility. A comprehensive guideline for selecting spinal flexibility assessment method(s) should be established via future studies. Level of Evidence: 4