Incidence and Risk Factors of Mechanical Complications After Posterior-Based Osteotomies for Correction of Moderate to Severe Adult Cervical Deformity: 1-Year and 2-Year Follow-up

Abstract

BACKGROUND: Rigid cervical deformity (CD) requires multilevel and/or high-grade osteotomies and long-construct fusions to achieve adequate correction. The incidence of mechanical complications (MCs) remains incompletely studied. OBJECTIVE: To define the incidence and risk factors for MC. METHODS: A retrospective review of consecutive patients with CD who underwent correction from 2010 to 2018 was performed. Inclusion criteria were cervical kyphosis >20° and/or cervical sagittal vertical axis (cSVA) >4 cm. MCs (junctional kyphosis/failure, pseudarthrosis, and implant failure) and reoperation at 1 and 2 yr were examined. RESULTS: Eighty-three patients were included. The mean age was 63.4 yr, and 61.0% were female. Fifty-three percent underwent 3-column osteotomies. After surgery, cervical parameters were significantly improved: cSVA (6.2 vs 3.8 cm, P 5° to be the threshold of risk for MCs and reoperation. CONCLUSION: Correction of CD is effective by posterior-based osteotomes, but MCs are relatively high at 1 and 2 yr. BMI >30 and preoperative CS >5° predispose patients for MC and reoperation.