Adherence to the Obeid coronal malalignment classification and a residual malalignment below 20 mm can improve surgical outcomes in adult spine deformity surgery

• Published in: European spine journal Vol. 32; no. 10; pp. 3673 - 3680
• Main Authors: Baroncini, Alice, Frechon, Paul, Bourghli, Anouar, Smith, Justin S., Larrieu, Daniel, Pellisé, Ferran, Pizones, Javier, Kleinstueck, Frank, Alanay, Ahmet, Kieser, David, Cawley, Derek T., Boissiere, Louis, Obeid, Ibrahim
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-10-2023; Springer Nature B.V
• Subjects: Adult; Bone surgery; Classification; Humans; Medicine; Medicine & Public Health; Neurosurgery; Original Article; Patients; Postoperative Period; Quality of Life; Retrospective Studies; Scoliosis - diagnostic imaging; Scoliosis - surgery; Surgery; Surgical Orthopedics; Surgical outcomes; Treatment Outcome; Health-related quality of life; Obeid coronal malalignment classification; Adult spinal deformity; Coronal alignment; Patient-related outcome measures; Mechanical complications
• ISSN: 0940-6719; 1432-0932
• DOI: 10.1007/s00586-023-07831-0

Purpose
Coronal balance is a major factor impacting the surgical outcomes in adult spinal deformity (ASD). The Obeid coronal malalignment (O-CM) classification has been proposed to improve the coronal alignment in ASD surgery. Aim of this study was to investigate whether a postoperative CM < 20 mm and adherence to the O-CM classification could improve surgical outcomes and decrease the rate of mechanical failure in a cohort of ASD patients.
Methods
Multicenter retrospective analysis of prospectively collected data on all ASD patients who underwent surgical management and had a preoperative CM > 20 mm and a 2-year follow-up. Patients were divided in two groups according to whether or not surgery had been performed in adherence to the guidelines of the O-CM classification and according to whether or not the residual CM was < 20 mm. The outcomes of interest were radiographic data, rate of mechanical complications and Patient-Reported Outcome Measures.
Results
At 2 years, adherence to the O-CM classification led to a lower rate of mechanical complications (40 vs. 60%). A coronal correction of the CM < 20 mm allowed for a significant improvement in SRS-22 and SF-36 scores and was associated with a 3.5 times greater odd of achieving the minimal clinical important difference for the SRS-22.
Conclusion
Adherence to the O-CM classification could reduce the risk of mechanic complications 2 years after ASD surgery. Patients with a residual CM < 20 mm showed better functional outcomes and a 3.5 times greater odd of achieving the MCID for the SRS-22 score.