Effectiveness of suspension bending cast for early-onset scoliosis

To evaluate the effectiveness of a novel suspension bending cast (SBC) technique for early-onset scoliosis (EOS) that enables coronal correction through suspension-assisted bending and facilitates derotational molding, and to identify factors associated with curve improvement.

A retrospective review was conducted on 49 patients with EOS who underwent SBC between 2011 and 2023. For inclusion, patients had to be < 10 years at casting initiation and have ≥ 2 years of follow-up. Curves were measured before the first cast, after the first cast, at the end of casting, and at final follow-up. We analyzed curve improvement, scoliosis type, rib phase, and rib-vertebral angle difference (RVAD).

Median age at initial casting was 44 months (interquartile range [IQR] 25-78). The median number of casts was 3 (IQR 2-6); the median follow-up was 58 months (IQR 35.0-81.6). The median curve was 63° before casting, corrected to 21° in the first cast, and 67° at final follow-up. Of the 49 patients, 30.6% went from casting to definitive fusion, and an additional 30.6% underwent additional surgery before definitive fusion, while the remaining 38.8% were "cured" or remain under non-operative management. Time from first cast application to any surgery was 38.6 months (IQR 21.9-58.5). Curve improvement (from initial to final) was associated with higher initial correction rates. Idiopathic scoliosis demonstrated greater initial correction than non-idiopathic scoliosis. No differences were observed in final curve or correction rate based on rib phase or RVAD.

Suspension bending casts showed high initial correction in patients with moderate to severe EOS and contributed to delayed surgical intervention. A higher correction rate after the first cast was associated with long-term curve improvement, indicating that initial correction of casting may be an important prognostic factor.