Benlong Shi1, Jing Guo1, Saihu Mao1, Zhiwei Wang2, Fiona W P Yu2, Kwong Man Lee2, Bobby K W Ng3, Zezhang Zhu1, Yong Qiu1, Jack C Y Cheng2, Tsz Ping Lam4. 1. Spine Surgery, the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, China; Joint Scoliosis Research Center of the Chinese University of Hong Kong & Nanjing University, Nanjing, China. 2. Department of Orthopaedics and Traumatology, Chinese University of Hong Kong, Hong Kong, China; Joint Scoliosis Research Center of the Chinese University of Hong Kong & Nanjing University, Nanjing, China. 3. Joint Scoliosis Research Center of the Chinese University of Hong Kong & Nanjing University, Nanjing, China. 4. Department of Orthopaedics and Traumatology, Chinese University of Hong Kong, Hong Kong, China; Joint Scoliosis Research Center of the Chinese University of Hong Kong & Nanjing University, Nanjing, China. Electronic address: tplam@ort.cuhk.edu.hk.
Abstract
STUDY DESIGN: A retrospective study. OBJECTIVES: To investigate curve evolution after brace weaning in adolescent idiopathic scoliosis (AIS) with reference to the Scoliosis Research Society (SRS) criteria. SUMMARY OF BACKGROUND DATA: Previous studies mainly focused on curve evolution during bracing in AIS. However, curve progression after brace weaning was not well addressed. METHODS: Braced AIS girls followed up for at least 2 years after brace weaning were reviewed. All patients had radiographs at initial visit, brace weaning, 6 months, 1 year, and 2 years after brace weaning, and last follow-up. Curve progression after brace weaning was separately defined as increase in Cobb angle >5 degrees and curve magnitude >45 degrees. The predictors for curve progression were identified using the independent t test. RESULTS: 200 AIS girls were reviewed. The average duration of follow-up after brace weaning was 51.4 ± 25.6 months. Compared with brace weaning, at 6 months, 1 year, 2 years and last follow-up after brace weaning, 50 (25.0%), 60 (30.0%), 93 (46.5%), and 87 (43.5%) patients, respectively, had curve progression >5 degrees; 0 (0%), 0 (0%), 2 (1%), and 2 (1%) patients, respectively, had surgery recommended; among those with Cobb angle ≤40 degrees at brace weaning, 7 (4.0%), 11 (6.3%), 16 (9.2%), and 18 (10.3%) patients, respectively, had Cobb angle >45 degrees; the mean progression magnitudes were 2.6 ± 5.8, 3.5 ± 5.8, 5.1 ± 6.5, and 5.4 ± 7.4 degrees, respectively; and the mean progression rates were 0.34 ± 0.83, 0.16 ± 0.56, 0.13 ± 0.39, and 0.006 ± 0.28 degrees/month, respectively. Cobb angle at brace weaning was associated with increase in Cobb angle >5 degrees (p = .033) and curve magnitude >45 degrees (p < .001) after brace weaning. CONCLUSIONS: Curve progression after brace weaning is observed in 43.5% AIS patients. The highest risk occurs within 6 months after brace weaning whereas Cobb angle remains stable after 2 years' follow-up. High Cobb angle at brace weaning indicates high risk of curve progression after brace weaning. LEVEL OF EVIDENCE: Level III.
STUDY DESIGN: A retrospective study. OBJECTIVES: To investigate curve evolution after brace weaning in adolescent idiopathic scoliosis (AIS) with reference to the Scoliosis Research Society (SRS) criteria. SUMMARY OF BACKGROUND DATA: Previous studies mainly focused on curve evolution during bracing in AIS. However, curve progression after brace weaning was not well addressed. METHODS: Braced AIS girls followed up for at least 2 years after brace weaning were reviewed. All patients had radiographs at initial visit, brace weaning, 6 months, 1 year, and 2 years after brace weaning, and last follow-up. Curve progression after brace weaning was separately defined as increase in Cobb angle >5 degrees and curve magnitude >45 degrees. The predictors for curve progression were identified using the independent t test. RESULTS: 200 AIS girls were reviewed. The average duration of follow-up after brace weaning was 51.4 ± 25.6 months. Compared with brace weaning, at 6 months, 1 year, 2 years and last follow-up after brace weaning, 50 (25.0%), 60 (30.0%), 93 (46.5%), and 87 (43.5%) patients, respectively, had curve progression >5 degrees; 0 (0%), 0 (0%), 2 (1%), and 2 (1%) patients, respectively, had surgery recommended; among those with Cobb angle ≤40 degrees at brace weaning, 7 (4.0%), 11 (6.3%), 16 (9.2%), and 18 (10.3%) patients, respectively, had Cobb angle >45 degrees; the mean progression magnitudes were 2.6 ± 5.8, 3.5 ± 5.8, 5.1 ± 6.5, and 5.4 ± 7.4 degrees, respectively; and the mean progression rates were 0.34 ± 0.83, 0.16 ± 0.56, 0.13 ± 0.39, and 0.006 ± 0.28 degrees/month, respectively. Cobb angle at brace weaning was associated with increase in Cobb angle >5 degrees (p = .033) and curve magnitude >45 degrees (p < .001) after brace weaning. CONCLUSIONS: Curve progression after brace weaning is observed in 43.5% AIS patients. The highest risk occurs within 6 months after brace weaning whereas Cobb angle remains stable after 2 years' follow-up. High Cobb angle at brace weaning indicates high risk of curve progression after brace weaning. LEVEL OF EVIDENCE: Level III.
Authors: Manon van den Bogaart; Barend J van Royen; Tsjitske M Haanstra; Marinus de Kleuver; Sayf S A Faraj Journal: Eur Spine J Date: 2019-01-03 Impact factor: 3.134