Proximal ­junctional ­kyphosis­ in ­Lenke ­C5­ curves. ­A ­comparison between­ anterior­ and­ posterior ­surgery

Abstract

AbstractBackground: Sagittal balance is critical for long-term results in the surgical handling of adolescent idiopathic scoliosis. Proximal junctional kyphosis could be defined as a radiographic findings in the fused and mobile spine transition in asymptomatic patients.Objective: To compare post-surgical proximal junctional kyphosis in Lenke C5 curves with two different surgical techniques: anterior and posterior instrumentation.Methods: Retrospective, controlled, non-randomized study of 37 patients with Lenke C5 adolescent idiopathic scoliosis, with short fusion from end-vertebra to end-vertebra. Group 1: 18 patients with anterior instrumented arthrodesis, and Group 2: 19 patients with posterior instrumented arthrodesis. The radiographic sagittal parameters measured were: 1) plumbline from the C7, 2) junctional kyphosis, 3) thoracic kyphosis, and 4) lumbar lordosis; with a minimum follow-up of two years.Results: Group 1: increase of junctional kyphosis between the preoperative period and a two-year follow-up, 6.27°­ (p = 0.0002). The incidence of pathologic junctional kyphosis was 17%. Group 2: increase of junctional kyphosis between the preoperative period and the follow-up, 4.63° (p = 0.0004). The incidence of pathologic junctional kyphosis was 16%.Conclusion: There were no significant differences between groups in the incidence of pathologic junctional kyphosis.