Analysis of spinopelvic sagittal alignment in adult patients with idiopathic scoliosis

English Keywords:Idiopathic scoliosis  Spine  Pelvic  Sagittal balance  Adult

English Abstract:

  【Abstract】 Objective：To analyze the spinopelvic sagittal alignment in adult patients with idiopathic scoliosis according to curve types.Method：The sagittal spinopelvic parameters and scoliosis curves types were analyzed retrospectively in standing radiographs of 83 adult patients（mean age 43.0 years） with adult idiopathic scoliosis，these parameters included cobb angle of primary scoliosis，thoracic kyphosis（TK），thoracolumbar junction kyphosis（TLJ），lumbar lordosis（LL），pelvic incidence（PI），sacrum slope（SS），pelvic tilt（PT） and sagittal vertical axis（SVA）.According to SRS classification，the patients were divided into two groups，thoracic curve and lumbar curve.All spinopelvic parameters between two groups were compared.The correlations between parameters as well as these parameters with age were analyzed.Result：The average age of 39 patients with thoracic curve was 40.9，while that for 44 patients with lumbar curve was 45.8.No age-related difference was noted between two groups.Also no difference for all spinopelvic parameters except SVA was noted.The SVA in patients with lumbar curve was significantly greater than that with thoracic curve（P＜0.05）.For patients less than 40 years old，all spinopelvic parameters between two groups showed no difference，while for patients older than 40 years old，SVA and PT in lumbar curve group were significant greater than those in thoracic curve group（P＜0.05）.In thoracic curve group，9 patients had SVA more than±50mm.Among them 7 patients were negative imbalance.In lumbar curve group，12 patients had SVA more than±50mm，and 8 patients of them were positive imbalance.In both two groups，there were significant correlations between LL and TK，LL and SS，PI and SS，PI and PT，SVA and LL，SVA and SS，SVA and PT，age and SVA，and age and PT.PI showed significant correlaion with LL in patients with thoracic curve while no correlation with LL in patients with lumbar curve.Unlike thoracic curve group，no relationship between PI and LL in lumbar curve group were noted，while there were significant correlations between age and LL，age and SS，PT and LL，and PT and SS.Conclusion：In adult patients with idiopathic scoliosis，there is no difference with respect to pelvic shape between thoracic and lumbar curves，and the pelvic is related to alignment of spine sagittal plane，age is related the imbalance of spine.Thoracic curve is apt to lead to negative imbalance，while lumbar curve is apt to lead to positive imbalance.