Objective To review the research progress of the risk factors for slip progression and the pathogenesis of lumbosacral spondylolisthesis, and to discuss the value of Spinal Deformity Study Group (SDSG) classification system for lumbosacral spondylolisthesis. Methods Recent articles about the risk factors for slip progression and the pathogenesis of lumbosacral spondylolisthesis were reviewed and comprehensively analyzed with SDSG classification system of lumbosacral spondylolisthesis. Results Pelvic incidence (PI) is the key pathogenic factor of lumbosacral spondylolisthesis. The Meyerding grade of slip, PI, sacro-pelvic balance, and spino-pelvic balance not only are the fundamental risk factors of slip progression, but also are the key factors to determine how to treat and influence the prognosis. Therefore, compared with Wiltse, Marchetti-Bartolozzi, and Mac-Thiong-Labelle classification systems of lumbosacral spondylolisthesis, SDSG classification based on these factors mentioned above, has better homogeneity between the subjects of subgroup, and better reliability, moreover, could better guide operative plan and judge the prognosis. Conclusion It is suggested that the SDSG classification system should be the standard classification for lumbosacral spondylolisthesis for the clinical and research work.
Objective To review the development of the reconstruction methods following total sacrectomy, and to provide reference for finding a better reconstruction method following total sacrectomy. Methods The case reports and biomechanical and finite element studies of reconstruction following total sacrectomy at home and abroad were searched. Development and current situation were summarized. Results After developing for nearly 30 years, great progress has been made in the reconstruction concept and fixation techniques. The fixation methods can be summarized as the following three strategies: spinopelvic fixation (SPF), posterior pelvic ring fixation (PPRF), and anterior spinal column fixation (ASCF). SPF has undergone technical progress from intrapelvic rod and hook constructs to pedicle and iliac screw-rod systems. PPRF and ASCF could improve the stability of the reconstruction system. Conclusion Reconstruction following total sacrectomy remains a challenge. Reconstruction combining SPF, PPRF, and ASCF is the developmental direction to achieve mechanical stability. How to gain biological fixation to improve the long-term stability is an urgent problem to be solved.