Sagittal alignment of diverse mechanical complications following adult spinal deformity surgery

• Published in: European spine journal Vol. 33; no. 5; pp. 1857 - 1867
• Main Authors: Pan, Changyu, Bourghli, Anouar, Larrieu, Daniel, Boissiere, Louis, Pizones, Javier, Alanay, Ahmet, PelIise, Ferran, Kleinstück, Frank, Obeid, Ibrahim
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.05.2024; Springer Nature B.V
• Subjects: Adult; Aged; Female; Humans; Kyphosis; Kyphosis - diagnostic imaging; Kyphosis - etiology; Kyphosis - surgery; Lordosis - diagnostic imaging; Lordosis - etiology; Lordosis - surgery; Lumbar Vertebrae - diagnostic imaging; Lumbar Vertebrae - surgery; Male; Medicine; Medicine & Public Health; Middle Aged; Neurosurgery; Original Article; Postoperative Complications - epidemiology; Postoperative Complications - etiology; Retrospective Studies; Spinal Curvatures - diagnostic imaging; Spinal Curvatures - surgery; Spinal Fusion - adverse effects; Spinal Fusion - instrumentation; Spinal Fusion - methods; Surgery; Surgical Orthopedics; Thoracic Vertebrae - diagnostic imaging; Thoracic Vertebrae - surgery; Thorax; Sagittal alignment; Adult spinal deformity; The global alignment and proportion (GAP) score; Mechanical complications
• DOI: 10.1007/s00586-023-08126-0
• ISSN: 0940-6719; 1432-0932

Purpose To compare the sagittal alignment of patients with diverse mechanical complications (MCs) following adult spinal deformity (ASD) surgery with that of patients without MCs. Methods A total of 371 patients who underwent ASD surgery were enrolled. The sagittal spinopelvic parameters were measured preoperatively and at the 6-month and last follow-up, and the global alignment and proportion (GAP) score was calculated. The subjects were divided into non-MC and MCs groups, and the MCs group was further divided into rod fracture (RF), screw breakage (SB), screw dislodgement (SD) and proximal junctional kyphosis (PJK) subgroups. Results Preoperatively, the RF group had greater thoracolumbar kyphosis (TLK) and relative upper lumbar lordosis (RULL); the SB group had the largest pelvic incidence (PI) and lumbar lordosis (LL); the SD group had the least global sagittal imbalance; and the PJK group had the highest thoracic kyphosis (TK), TLK and RULL. At the last follow-up, the RF and SB groups featured a large PI minus LL (PI-LL), while the PJK group featured a prominent TK; all the MCs subgroups had sagittal malalignment and a higher GAP score, and the SB group had the most severe cases. Logistic regressions showed that the relative spinopelvic alignment (RSA) score was correlated with RF, SB and SD, while the RSA and age scores were associated with PJK. Conclusion Each patient with MCs had individual characteristics in the sagittal plane following ASD surgery, which may be helpful to understand the pathophysiology of poor sagittal alignment with its subsequent MCs and guide an eventual revision strategy.