TY - JOUR
T1 - Surgical Predictors for Prevention of Postoperative Shoulder Imbalance in Lenke Type 2A Adolescent Idiopathic Scoliosis
AU - Sato, Tatsuya
AU - Yonezawa, Ikuho
AU - Matsumoto, Hiroko
AU - Otomo, Nao
AU - Suzuki, Teppei
AU - Manabe, Nodoka
AU - Demura, Satoru
AU - Watanabe, Kota
AU - Saito, Toshiki
AU - Nohara, Ayato
AU - Kurakawa, Takuto
AU - Shimizu, Takachika
AU - Uno, Koki
AU - Matsumoto, Morio
AU - Kawakami, Noriaki
N1 - Publisher Copyright:
© 2021 Wolters Kluwer Health, Inc. All rights reserved.
PY - 2022/2/15
Y1 - 2022/2/15
N2 - Study Design. Multicenter, retrospective cohort study. Objective. The aim of this study was to investigate the occurrence and surgical predictors of postoperative shoulder imbalance (PSI) in Lenke type 2A adolescent idiopathic scoliosis (AIS). Summary of Background Data. Although several studies have investigated the factors influencing PSI in Lenke type 2 curves, no studies have analyzed PSI-related factors considering upper instrumented vertebra (UIV) and lumbar modifier type simultaneously. Methods. Patients with Lenke Type 2A AIS treated by spinal fusion were retrospectively identified and their data were extracted from six spine centers in Japan. Inclusion criteria were age between 10 and 20years at surgery, UIV=T2, major curve 408 to 908, and follow-up for 24 to 30months after surgery. We analyzed patient characteristics, surgical characteristics, and preoperative and immediate-postoperative radiographic parameters. We defined patients with lower instrumented vertebra (LIV) equal or proximal to the last touching vertebra (LTV) as selective thoracic fusion (STF-LTV) and patients with LIV distal to the LTV as non-STF-LTV. t Tests, Mann-Whitney U test, χ2 tests, Fisher exact tests, and multivariate logistic regression were used for statistical analyses. Results. Among the 99 consecutive patients with a mean follow-up of 25.6months, PSI was seen in 27 (27.3%) patients immediately after and in 17 (17.2%) patients at 24 to 30months. The univariate analysis revealed that the significant risk factors of PSI were preoperative radiographical shoulder height, non-STF-LTV, and high main thoracic curve (MTC) correction (immediate-postoperative MTC correction rate: ≥70%), with PSI incidence of 40.0%. The multivariate logistic regression analysis indicated that interaction term of non-STF-LTV and high MTC correction was an independent risk factor for PSI (non-STF-LTV and high MTC correction, odds ratio: 5.167, 95% confidence interval: 1.470-18.159, P=0.010). Conclusion. To prevent PSI in Lenke Type 2A AIS patients, surgeons should avoid the combination of non-STF-LTV and high MTC correction in those surgeries with UIV as T2.
AB - Study Design. Multicenter, retrospective cohort study. Objective. The aim of this study was to investigate the occurrence and surgical predictors of postoperative shoulder imbalance (PSI) in Lenke type 2A adolescent idiopathic scoliosis (AIS). Summary of Background Data. Although several studies have investigated the factors influencing PSI in Lenke type 2 curves, no studies have analyzed PSI-related factors considering upper instrumented vertebra (UIV) and lumbar modifier type simultaneously. Methods. Patients with Lenke Type 2A AIS treated by spinal fusion were retrospectively identified and their data were extracted from six spine centers in Japan. Inclusion criteria were age between 10 and 20years at surgery, UIV=T2, major curve 408 to 908, and follow-up for 24 to 30months after surgery. We analyzed patient characteristics, surgical characteristics, and preoperative and immediate-postoperative radiographic parameters. We defined patients with lower instrumented vertebra (LIV) equal or proximal to the last touching vertebra (LTV) as selective thoracic fusion (STF-LTV) and patients with LIV distal to the LTV as non-STF-LTV. t Tests, Mann-Whitney U test, χ2 tests, Fisher exact tests, and multivariate logistic regression were used for statistical analyses. Results. Among the 99 consecutive patients with a mean follow-up of 25.6months, PSI was seen in 27 (27.3%) patients immediately after and in 17 (17.2%) patients at 24 to 30months. The univariate analysis revealed that the significant risk factors of PSI were preoperative radiographical shoulder height, non-STF-LTV, and high main thoracic curve (MTC) correction (immediate-postoperative MTC correction rate: ≥70%), with PSI incidence of 40.0%. The multivariate logistic regression analysis indicated that interaction term of non-STF-LTV and high MTC correction was an independent risk factor for PSI (non-STF-LTV and high MTC correction, odds ratio: 5.167, 95% confidence interval: 1.470-18.159, P=0.010). Conclusion. To prevent PSI in Lenke Type 2A AIS patients, surgeons should avoid the combination of non-STF-LTV and high MTC correction in those surgeries with UIV as T2.
KW - Adolescent idiopathic scoliosis
KW - Double thoracic curve
KW - Fusion length
KW - Lenke Type 2A
KW - Lower instrumented vertebra
KW - Posterior correction and spinal fusion
KW - Postoperative shoulder imbalance
KW - Radiographic shoulder height
KW - Selective thoracic fusion
KW - Upper instrumented vertebra
UR - http://www.scopus.com/inward/record.url?scp=85123813495&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85123813495&partnerID=8YFLogxK
U2 - 10.1097/BRS.0000000000004135
DO - 10.1097/BRS.0000000000004135
M3 - Article
C2 - 34075011
AN - SCOPUS:85123813495
SN - 0362-2436
VL - 47
SP - E132-E141
JO - Spine
JF - Spine
IS - 4
ER -