Does Coronal Plane Deformity Matter in Cervicothoracic Kyphosis Corrective Surgery? The Prevalence of Cervical Scoliosis and Influence on the Outcomes of Cervical Deformity Surgery.

Abstract

Study designRetrospective review of a prospective, multicenter adult cervical deformity (CD) database.ObjectiveInvestigate the prevalence and clinical significance of combined cervical scoliosis (CS) and cervical kyphosis (CK) among patients undergoing surgical management of CD.Summary of background dataAlthough adult CD patients may have both CS and CK, few studies have confirmed prevalence of CK and CS and associated radiographic and clinical findings.MethodsPatients undergoing surgery for CD (defined as C2-C7 ≥10° kyphosis, cervical sagittal vertical axis (SVA) >4 cm, or C2-C7 coronal Cobb angle ≥10°) were included. CS was defined as C2-C7 coronal Cobb angle ≥10°.Results114 patients were included (mean age 62.5 y, 51.8% female). 14 patients (12.3%) had combined CS and CK, and 100 patients (87.7%) had CK alone. Pre-operative maximum cervical coronal Cobb angle was 3.9° in the CK alone group and 14.6° in the combined CS and CK group. In the combined CS and CK group, this value improved to 8.1° post-operatively (P=0.0007 vs. pre-operative), but CS ≥10° was still present in 3 patients, with a mean correction percentage of only 48.0% of initial CS.No significant differences were observed between the CK only and combined CS and CK groups with regard to baseline sagittal parameters, change between immediate post-operative and baseline sagittal parameters, surgical approach, age, or baseline HRQOL. Patients with combined CS and CK were more frequently female than patients with CK alone (85.7% vs. 41.2%, P=0.0066).ConclusionsThe vast majority of patients presented with CK alone (88%), and only 12% of adult CD patients had combined CS and CK. Because of the significant residual coronal plane deformity-approximately 50%-surgical correction should be focused on both coronal and sagittal plane deformity in the combined CS and CK group.