Influence of screw density on thoracic kyphosis restoration in hypokyphotic adolescent idiopathic scoliosis
Abstract Background Previous studies have reported that rod composition and diameter, as well as the correction technique are key factors associated with thoracic kyphosis (TK) restoration. However, few study has analyzed the correlation between screw density and TK restoration in hypokyphotic adole...
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| Format: | Article |
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BMC
2017-12-01
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| Series: | BMC Musculoskeletal Disorders |
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| Online Access: | http://link.springer.com/article/10.1186/s12891-017-1877-6 |
| _version_ | 1818975281492262912 |
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| author | Ming Luo Honghui Jiang Wengang Wang Ning Li Mingkui Shen Peng Li Genzhong Xu Lei Xia |
| author_facet | Ming Luo Honghui Jiang Wengang Wang Ning Li Mingkui Shen Peng Li Genzhong Xu Lei Xia |
| author_sort | Ming Luo |
| collection | DOAJ |
| description | Abstract Background Previous studies have reported that rod composition and diameter, as well as the correction technique are key factors associated with thoracic kyphosis (TK) restoration. However, few study has analyzed the correlation between screw density and TK restoration in hypokyphotic adolescent idiopathic scoliosis (AIS). Methods Fifty-seven thoracic AIS patients with preoperative TK < 10° treated with all pedicle screw fixation with a minimum 2-year follow-up were recruited. Preoperative and postoperative radiographic measurements, and information of posterior instrumentation were reviewed. Pearson and Spearman correlation coefficient analysis were used to assess relationships between change in TK and number of variables. Then, the included patients were classified into two groups (Group 1: postoperative TK ≥ 20°; Group 2: postoperative TK < 20°) to evaluate the influence factors of TK restoration. Results The average preoperative TK was 4.75°, which was significantly restored to 17.30° (P < 0.001). Significant correlations were found between change in TK and flexibility of major thoracic curve (r = 0.357, P = 0.006), preoperative TK (r = −0.408, P = 0.002), and screw density of concave side (r = 0.306, P = 0.021), respectively. In the subgroup comparison, 17 patients (29.8%) maintain the postoperative TK ≥ 20°, increased flexibility of major thoracic curve (P < 0.001), screw number of concave side (P = 0. 029), and cobalt chromium rods (P = 0.041) were found in the group of postoperative TK ≥ 20°. Conclusions TK restoration remains a challenge for AIS patients with hypokyphosis, especially for the poor flexibility ones. Except for thicker and cobalt chromium rods, screw density of concave side might be another positive predictor of restoring normal kyphosis, which provides a stronger corrective force on the sagittal plane with more pedicle screws. |
| first_indexed | 2024-12-20T15:53:28Z |
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| id | doaj.art-7549f2ff49c3403dbb5572d0895fda66 |
| institution | Directory Open Access Journal |
| issn | 1471-2474 |
| language | English |
| last_indexed | 2024-12-20T15:53:28Z |
| publishDate | 2017-12-01 |
| publisher | BMC |
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| series | BMC Musculoskeletal Disorders |
| spelling | doaj.art-7549f2ff49c3403dbb5572d0895fda662022-12-21T19:34:34ZengBMCBMC Musculoskeletal Disorders1471-24742017-12-011811810.1186/s12891-017-1877-6Influence of screw density on thoracic kyphosis restoration in hypokyphotic adolescent idiopathic scoliosisMing Luo0Honghui Jiang1Wengang Wang2Ning Li3Mingkui Shen4Peng Li5Genzhong Xu6Lei Xia7Institute of Spinal Deformity, the First Affiliated Hospital of Zhengzhou UniversityDepartment of Orthopaedic Surgery, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science & TechnologyInstitute of Spinal Deformity, the First Affiliated Hospital of Zhengzhou UniversityInstitute of Spinal Deformity, the First Affiliated Hospital of Zhengzhou UniversityInstitute of Spinal Deformity, the First Affiliated Hospital of Zhengzhou UniversityInstitute of Spinal Deformity, the First Affiliated Hospital of Zhengzhou UniversityInstitute of Spinal Deformity, the First Affiliated Hospital of Zhengzhou UniversityInstitute of Spinal Deformity, the First Affiliated Hospital of Zhengzhou UniversityAbstract Background Previous studies have reported that rod composition and diameter, as well as the correction technique are key factors associated with thoracic kyphosis (TK) restoration. However, few study has analyzed the correlation between screw density and TK restoration in hypokyphotic adolescent idiopathic scoliosis (AIS). Methods Fifty-seven thoracic AIS patients with preoperative TK < 10° treated with all pedicle screw fixation with a minimum 2-year follow-up were recruited. Preoperative and postoperative radiographic measurements, and information of posterior instrumentation were reviewed. Pearson and Spearman correlation coefficient analysis were used to assess relationships between change in TK and number of variables. Then, the included patients were classified into two groups (Group 1: postoperative TK ≥ 20°; Group 2: postoperative TK < 20°) to evaluate the influence factors of TK restoration. Results The average preoperative TK was 4.75°, which was significantly restored to 17.30° (P < 0.001). Significant correlations were found between change in TK and flexibility of major thoracic curve (r = 0.357, P = 0.006), preoperative TK (r = −0.408, P = 0.002), and screw density of concave side (r = 0.306, P = 0.021), respectively. In the subgroup comparison, 17 patients (29.8%) maintain the postoperative TK ≥ 20°, increased flexibility of major thoracic curve (P < 0.001), screw number of concave side (P = 0. 029), and cobalt chromium rods (P = 0.041) were found in the group of postoperative TK ≥ 20°. Conclusions TK restoration remains a challenge for AIS patients with hypokyphosis, especially for the poor flexibility ones. Except for thicker and cobalt chromium rods, screw density of concave side might be another positive predictor of restoring normal kyphosis, which provides a stronger corrective force on the sagittal plane with more pedicle screws.http://link.springer.com/article/10.1186/s12891-017-1877-6Adolescent idiopathic scoliosisHypokyphosisThoracic kyphosisScrew density |
| spellingShingle | Ming Luo Honghui Jiang Wengang Wang Ning Li Mingkui Shen Peng Li Genzhong Xu Lei Xia Influence of screw density on thoracic kyphosis restoration in hypokyphotic adolescent idiopathic scoliosis BMC Musculoskeletal Disorders Adolescent idiopathic scoliosis Hypokyphosis Thoracic kyphosis Screw density |
| title | Influence of screw density on thoracic kyphosis restoration in hypokyphotic adolescent idiopathic scoliosis |
| title_full | Influence of screw density on thoracic kyphosis restoration in hypokyphotic adolescent idiopathic scoliosis |
| title_fullStr | Influence of screw density on thoracic kyphosis restoration in hypokyphotic adolescent idiopathic scoliosis |
| title_full_unstemmed | Influence of screw density on thoracic kyphosis restoration in hypokyphotic adolescent idiopathic scoliosis |
| title_short | Influence of screw density on thoracic kyphosis restoration in hypokyphotic adolescent idiopathic scoliosis |
| title_sort | influence of screw density on thoracic kyphosis restoration in hypokyphotic adolescent idiopathic scoliosis |
| topic | Adolescent idiopathic scoliosis Hypokyphosis Thoracic kyphosis Screw density |
| url | http://link.springer.com/article/10.1186/s12891-017-1877-6 |
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