Curve Characteristics and Response of Sciatic and Olisthesis Scoliosis Following L5/S1 Transforaminal Lumbar Interbody Fusion in Adolescent Lumbar Spondylolisthesis

Abstract BACKGROUND Lumbosacral spondylolisthesis-induced scoliosis is a rare clinical entity. Sagittal reconstruction and the coronal curve evolution after surgery for spondylolisthesis have not been investigated in depth. OBJECTIVE To compare the curve characteristics between sciatic scoliosis and olisthetic scoliosis and to further investigate the effects of lumbosacral transforaminal lumbar interbody fusion (TLIF) on scoliosis evolution. METHODS Adolescents with sciatic scoliosis group (SS group) or olisthetic scoliosis group (OS group) who underwent L5/S1 TLIF from 2010 to 2017 and were followed up for at least 2 yr were retrospectively reviewed. Radiographic parameters and patient-reported outcomes were evaluated. RESULTS There were 20 patients in the SS group (M/F: 8/12; age: 15.6 ± 2.2 yr) and 16 in the OS group (M/F: 6/10; age: 16.8 ± 2.5 yr). Both groups had similar preoperative Cobb angles, but more patients with coronal imbalance were observed in the SS group. Moreover, the OS group showed significantly larger L5 tilt and rotation. After surgery, the slip reduction rate of the SS group and OS group were 76.1% ± 12.4% and 79.4% ± 9.6%, respectively. Scoliosis resolution was observed in all patients in the SS group but only in 9 patients (56.2%) in the OS group. Patients with failed scoliosis resolution in the OS group were older and had a larger Cobb angle and L5 rotation compared with those with successful scoliosis resolution. CONCLUSION Lumbosacral TLIF can achieve satisfactory slip reduction and scoliosis resolution. Sciatic scoliosis often presents with coronal imbalance but also a preferable curve prognosis. A large Cobb angle and L5 rotation may hinder the resolution of olisthetic scoliosis.