Trunk imbalance in adolescent idiopathic scoliosis

Abstract Background Context Trunk imbalance (i.e. frontal trunk shift measured with a plumbline from C7 to S1) is part of the clinical evaluation in adolescent idiopathic scoliosis (AIS) but its prevalence and relationship with scoliosis, back pain and health related factors is not well documented. Purposes Principal objectives are to document trunk imbalance prevalence and to explore the association between trunk imbalance and the following factors: Cobb angle, type of scoliosis, back pain, function, mental health and self-image. Secondary objectives are to determine back pain prevalence and the relationship between back pain and each of the following: Cobb angle, function, mental health and self-image. Study Design/Setting This is a cross-sectional study in a scoliosis clinic of a tertiary university hospital centre. Patient Sample Youth with adolescent idiopathic scoliosis (N=55). Outcome Measures Trunk imbalance prevalence and magnitude, back pain prevalence and intensity using the Numerical Pain Rating Scale (NPRS) and the Scoliosis Research Society-22 (SRS-22) pain score and Function, Self-image, Mental health of the SRS-22. Methods Trunk imbalance and back pain were assessed in 55 patients with AIS (Cobb angle 10-60°). Patients completed SRS-22 questionnaire and the NPRS. Correlations were done between trunk imbalance and scoliosis (Cobb angle, type of scoliosis), back pain (NPRS and SRS-22 pain score) and health related factors using Pearson correlation coefficients (r) and logistic regression models. Results Trunk imbalance prevalence is 85% and back pain prevalence is 73%. We found fair to moderate significant positive correlation between trunk imbalance and Cobb angle (r = 0.32 to 0.66, p