Retrospective review of a radiographic database of high-grade spondylolisthesis patients in comparison with asymptomatic controls. To analyze the sagittal spinopelvic alignment in high-grade spondylolisthesis patients and identify subgroups that may require reduction to restore sagittal balance. High-grade spondylolisthesis is associated with an abnormally high pelvic incidence (PI); however, the spatial orientation of the pelvis, determined by sacral slope (SS) and pelvic tilt (PT), is not known. We hypothesized that sagittal spinal alignment would vary with the pelvic orientation. Digitized sagittal radiographs of 133 high-grade spondylolisthesis patients (mean age, 17 years) were measured to determined sagittal alignment. K-means cluster analysis identified 2 groups based on the PT and SS, which were compared by paired t test. Comparisons were made to asymptomatic controls matched for PI. High-grade spondylolisthesis patients had a mean PI of 78.9 degrees +/- 12.1 degrees . Cluster analysis identified a retroverted, unbalanced pelvis group with high PT (36.5 degrees +/- 8.0 degrees )/low SS (40.3 degrees +/- 9.0 degrees ) and a balanced pelvic group with low PT (mean 21.3 degrees +/- 8.2 degrees )/high SS (59.9 degrees +/- 11.2 degrees ). The retroverted pelvis group had significantly greater L5 incidence and lumbosacral angle with less thoracic kyphosis than the balanced pelvic group. A total of 83% of controls had a "balanced pelvis" based on the categorization by SS and PT. Analysis of sagittal alignment of high-grade spondylolisthesis patients revealed distinct groups termed "balanced" and "unbalanced" pelvis. The PT and SS were similar in controls and balanced pelvis patients. Unbalanced pelvis patients had a sagittal spinal alignment that differed from the balanced pelvis and control groups. Treatment strategies for high-grade spondylolisthesis should reflect the different mechanical strain on the spinopelvic junction in each group; reduction techniques might be considered in patients with an unbalanced pelvis high-grade spondylolisthesis.

The two main societies clinically dealing with idiopathic scoliosis are the Scoliosis Research Society (SRS), founded in 1966, and the international Society on Scoliosis Orthopedic and Rehabilitation Treatment (SOSORT), started in 2004. Inside the SRS, the Non-Operative Management Committee (SRS-NOC) has the same clinical interest of SOSORT, that is the Orthopaedic and Rehabilitation (or Non-Operative, or conservative) Management of idiopathic scoliosis patients. The aim of this paper is to present the results of a Consensus among the best experts of non-operative treatment of Idiopathic Scoliosis, as represented by SOSORT and SRS, on the recommendation for research studies on treatment of Idiopathic Scoliosis. The goal of the consensus statement is to establish a framework for research with clearly delineated inclusion criteria, methodologies, and outcome measures so that future meta- analysis or comparative studies could occur. A Delphi method was used to generate a consensus to develop a set of recommendations for clinical studies on treatment of Idiopathic Scoliosis. It included the development of a reference scheme, which was judged during two Delphi Rounds; after this first phase, it was decided to develop the recommendations and 4 other Delphi Rounds followed. The process finished with a Consensus Meeting, that was held during the SOSORT Meeting in Wiesbaden, 8–10 May 2014, moderated by the Presidents of SOSORT (JP O’Brien) and SRS (SD Glassman) and by the Chairs of the involved Committees (SOSORT Consensus Committee: S Negrini; SRS Non-Operative Committee: MT Hresko). The Boards of the SRS and SOSORT formally accepted the final recommendations. The 18 Recommendations focused: Research needs (3), Clinically significant outcomes (4), Radiographic outcomes (3), Other key outcomes (Quality of Life, adherence to treatment) (2), Standardization of methods of non-operative research (6).

Background: Tranexamic acid (TXA) is an antifibrinolytic drug that reduces surgical blood loss. Evidence supporting its efficacy in surgery for adolescent idiopathic scoliosis is not robust. This trial was designed to validate the clinical efficacy of TXA in surgery for adolescent idiopathic scoliosis. Methods: This institutional review board-approved prospective double-blinded trial involved 111 patients with adolescent idiopathic scoliosis who were randomized to receive either a placebo or TXA (50-mg/kg loading dose and 10-mg/kg/h infusion). Power analysis indicated that 50 patients per group would provide power to detect a >20% difference in blood loss. Two-way analysis of variance (ANOVA) was applied to compare blood loss rates (slopes) using the group-by-time interaction F test. Results: The risk of clinically relevant blood loss (>20 mL/kg) was more than twice as high in the placebo group than in the TXA group (44% versus 21%, relative risk = 2.1, 95% confidence interval = 1.2 to 3.7). Compared with the placebo group, the TXA group had a 27% reduction in intraoperative blood loss, a significantly lower rate of intraoperative bleeding per hour (mean and standard deviation, 190 ± 73 versus 230 ± 80 mL, p = 0.01; F = 9.77, p < 0.001) and per fused spinal level (82 ± 32 versus 110 ± 40 mL, p < 0.001), less intraoperative blood loss (836 ± 373 versus 1,031 ± 484 mL, p = 0.02), and less postoperative bleeding (in the drain) (498 ± 228 versus 645 ± 318 mL, p = 0.009). Six patients who received a placebo and no patient who received TXA required an allogenic blood transfusion. No perioperative adverse events, including thromboembolic events or seizures, were observed. Three independent factors were predictive of blood loss: TXA administration, duration of surgery, and number of levels fused. Greater intraoperative blood loss was the only independent variable predictive of a longer hospital stay. Conclusions: Use of TXA in patients undergoing surgery for adolescent idiopathic scoliosis significantly reduced blood loss, by 27%, compared with that in the placebo group. The rate of intraoperative blood loss per hour and per level fused and the amount of postoperative blood loss were significantly lower in the TXA group. More placebo-treated patients received allogenic blood. Patients with greater intraoperative blood loss spent a longer time in the hospital. Level of Evidence: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Reduction of severe spondylolisthesis is controversial. Publications have emphasized the techniques of reduction and associated complications, but there is little knowledge about the effect of reduction on the sagittal balance of the spine and pelvis in the postoperative patient. This study evaluated the effect of surgical reduction and instrumented fusion of spondylolisthesis on the pelvic anatomy and spinopelvic sagittal balance. Methods: This is a retrospective study of 26 adolescents (mean age, 13.1 ± 3.3 years) who had partial surgical reduction and posterior instrumented fusion L4 to sacrum to treat high-grade spondylolisthesis. All patients had radiographs that allowed measurement of sagittal spinopelvic parameters at preoperative, postoperative, and at a minimum of 2 years' follow-up (mean, 7.5 ± 5.4 years). A 10-degree reduction in lumbosacral angle and/or 10% reduction of anterior listhesis confirmed the reduction. Radiographic measurements were statistically compared to determine correlations between reduction and sagittal balance. Results: Pelvic incidence increased in 5 (24%) of 21 patients who had posterior instrumented fusion. Pelvic version improved in patients with unbalanced spondylolisthesis as evidenced by reduction of pelvic tilt or/and increased sacral slope. Mean pelvic tilt improved by 5.7 degrees (95% confidence interval, 1.5-9.8 degrees), and mean sacral slope improved by 11.4 degrees (95% confidence interval, 5.9-17.0 degrees). Two of 6 patients with a balanced spondylolisthesis developed a retroverted sacrum at follow-up. There was poor correlation between the amount of surgical reduction (improvement in L5 slip and lumbosacral angle) and the changes in pelvic version. Clinical Relevance: Partial reduction and instrumented fusion of spondylolisthesis may lead to increased pelvic incidence due to sacroiliac joint motion or sacral remodeling. In unbalanced spondylolisthesis, pelvic sagittal balanced improved in 75% of patients but did not correlate to the amount of reduction of spondylolisthesis. Other factors, such as achievement of solid arthrodesis, may be more important than reduction of spondylolisthesis in determining spinopelvic sagittal balance. Level of Evidence: IV-case series

A classification of lumbosacral spondylolisthesis has been proposed recently. This classification describes eight distinct types of spondylolisthesis based on the slip grade, the degree of dysplasia, and the sagittal sacro-pelvic balance. The objectives of this study are to assess the reliability of this classification and to propose a new and refined classification.