Three-column osteotomy surgery versus standard surgical management for the correction of adult spinal deformity: a cohort study

BACKGROUND: The aim of this study was to analyze and compare the surgical data, clinical outcomes, and complications between three-column osteotomy (3-COS) and standard surgical management (SSM) for the treatment of adult spine deformity (ASD). METHODS: A total of 112 patients who underwent consecutive 3-COS (n = 48) and SSM (n = 64) procedures for ASD correction at a single institution from 2001 to 2011 were reviewed in this study. The outcomes were assessed using the Scoliosis Research Society (SRS)-22 scores. The complications of patients with 3-COS and SSM were also compared. RESULTS: No significant differences were found in patient characteristics between SSM and 3-COS groups. Surgical data and radiographic parameters showed that the patients of the 3-COS group suffered more severe ASD than those of the SSM group. The distribution of surgical complications revealed that SSM group underwent more complications than 3-COS groups with no significant differences. At final follow-up, the total SRS-22 score of SSM was not significant between pre-operation and post-operation. However, the total SRS-22 score of 3-COS at final follow-up was significantly higher than pre-operation. CONCLUSION: For severe ASD patients with high grade pelvic incidence (PI), pelvic tilt (PT), and PI/lumbar lordosis (LL) mismatch and who have subjected to spine surgeries more than twice before, 3-COS might be more effective than SSM in improving the clinical outcomes. However, due to the higher reoperation rate of 3-COS, SSM may be more appropriate than SSM for correcting the not serious ASD patients

Modeling the Insulin-Like Growth Factor System in Articular Cartilage

IGF signaling is involved in cell proliferation, differentiation and apoptosis in a wide range of tissues, both normal and diseased, and so IGF-IR has been the focus of intense interest as a promising drug target. In this computational study on cartilage, we focus on two questions: (i) what are the key factors influencing IGF-IR complex formation, and (ii) how might cells regulate IGF-IR complex formation? We develop a reaction-diffusion computational model of the IGF system involving twenty three parameters. A series of parametric and sensitivity studies are used to identify the key factors influencing IGF signaling. From the model we predict the free IGF and IGF-IR complex concentrations throughout the tissue. We estimate the degradation half-lives of free IGF-I and IGFBPs in normal cartilage to be 20 and 100 mins respectively, and conclude that regulation of the IGF half-life, either directly or indirectly via extracellular matrix IGF-BP protease concentrations, are two critical factors governing the IGF-IR complex formation in the cartilage. Further we find that cellular regulation of IGF-II production, the IGF-IIR concentration and its clearance rate, all significantly influence IGF signaling. It is likely that negative feedback processes via regulation of these factors tune IGF signaling within a tissue, which may help explain the recent failures of single target drug therapies aimed at modifying IGF signaling.National Health and Medical Research Council (Australia) (APP1051455