Sagittal spinopelvic alignment in various curve patterns in adolescent idiopathic scoliosis

English Keywords:Adolescent idiopathic scoliosis  Sagittal spinopelvic alignment  Cervical sagittal angle  Curve type

English Abstract:

  【Abstract】 Objectives: To compare the sagittal spinopelvic alignment of adolescent idiopathic scoliosis(AIS) patients with various curve patterns. Methods: 161 adolescent idiopathic scoliosis(AIS) patients retrospectively reviewed in our department from September 2013 to December 2014. Among them, there were 34 males and 127 females. The average age was 14.6±2.1 years(range, 12-17 years). Main Cobb angle was obtained from preoperative full-spine standing coronal X-ray film. Sagittal spinal and pelvic parameters were measured from the standing lateral radiograph, including cervical sagittal angle(CSA), thoracic kyphosis(TK), lumbar lordosis(LL), pelvic incidence (PI), sacrum slope(SS) and pelvic tilt(PT). According to the various curve types, the patients were classified into single thoracic(ST), double thoracic(DT) and major lumbar(ML) curve groups. The sagittal spinopelvic parameters were analyzed among the 3 groups by using one-way ANOVA. Pearson analysis was used to investigate the relationship among parameters. Results: 61 patients were in the ST group with a mean Cobb angle of 51.2°±8.7°, 40 in the DT group with a mean Cobb angle of 53.7°±5.2°, and 60 in the ML group with a mean Cobb angle of 48.9°±4.8°. There was no significant difference among the 3 groups with regard to sex and age distribution. No significant difference in the magnitude of Cobb angle was observed among the 3 groups(P>0.05). The CSA and TK in the ST group were significantly lower than those in the DT and ML groups(P<0.05), but there was no significant difference between the latter 2 groups(P>0.05). No significant difference was found in the other parameters among the 3 groups(P>0.05). The CSA was correlated with TK in all 3 groups(ST group: r=0.73, P<0.05; DT group: r=0.29, P<0.05; ML group: r=0.60, P<0.05), but not correlated with LL and pelvic parameters(PI, SS and PT). In the DT groups TK was correlated with LL(r=0.40, P<0.05), but no correlation was found in the other groups(P>0.05). Conclusions: The AIS patients with ST curve has a lower CSA than the patients with DT and ML curves, and the CSA is in association with TK in all the 3 curves. The TK is lower in the ST group compared with that in the other groups. Only the TK in the patients with DT curve is correlated with LL, and no correlation is found in the ST and ML curve patients.