Guided bone regeneration is a promising means for reconstructing bone defects in the cranium. The present study was performed to better define those factors that affect osteogenesis in the cranium. The authors studied a single animal model, investigating the contribution of the dura, the pericranium, and the adjacent calvarial bone in the process of calvarial regeneration in both mature and immature animals. Bilateral, 100-mm2, parietal calvariectomies were performed in immature (n = 16) and mature (n = 16) rabbits. Parietal defects were randomized to one of four groups depending on the differential blockade of the dura and/or the pericranium by expanded polytetrafluoroethylene membranes. Animals were humanely killed after 12 weeks, and histometric analysis was performed to quantitate the area of the original bone defect, new bone formation, and new bone density. Bone formation was quantified separately both at the periphery and in the center of the defects. Extrasite bone formation was also quantified both on the dural and on the pericranial sides of the barriers. Bone regeneration was incomplete in all groups over the 12-week study period, indicating that complete bone healing was not observed in any group. The dura was more osteogenic than the pericranium in mature and immature animals, as there was significantly more extrasite bone formed on the dural side in the double expanded polytetrafluoroethylene barrier groups. In both the dural and the double expanded polytetrafluoroethylene barrier groups, dural bone production was significantly greater in immature compared with mature animals. The dura appeared to be the source of central new bone, because dural blockade in the dural and double expanded polytetrafluoroethylene groups resulted in a significant decrease in central bone density in both mature and immature animals. Paradoxically, isolation of the pericranium in mature animals resulted in a significant reduction in total new bone area, whereas pericranial contact appeared to enhance peripheral new bone formation, with the control group having the greatest total new bone area. The present study establishes a model to quantitatively study the process of bone regeneration in calvarial defects and highlights differences in the contribution of the dura and pericranium to calvarial bone regeneration between infant and adult animals. On the basis of these findings, the authors propose that subsequent studies in which permeability of the expanded polytetrafluoroethylene membranes is altered to permit migration of osteoinductive proteins into the defect while blocking prolapse of adjacent soft tissues may help to make guided bone regeneration a realistic alternative for the repair of cranial defects.
Study Design Systematic review and meta-analysis. Objectives The need for definitive fusion for growing rod graduates is a controversial topic in the management of Early-onset scoliosis (EOS) patients. The authors performed a systematic review and meta-analysis on the available literature to evaluate the outcomes of growing rod graduates undergoing final fusion or observation with implants in-situ. Methods An extensive literature search was carried out aimed at identifying articles reporting outcomes in growing rod graduates. Apart from the study characteristics and demographic details, the extracted data included Cobb’s correction, trunk height parameters, and revision rate. The extracted data was analyzed and forest plots were generated to draw comparisons between the observation and fusion groups. Results Of the 11 included studies, 6 were case-control and 5 were case series. The authors did not find any significant difference between the 2 groups with respect to the pre-index and final Cobb’s correction, T1-T12 or T1-S1 height gain in either over-all, or sub-analysis with case-control studies. The meta-analysis showed a significantly higher revision rate in patients undergoing a definitive fusion procedure. Conclusion The current analysis revealed comparable outcomes in terms of correction rate and gain in the trunk height but a lesser need of revisions in observation sub-group. The lack of good quality evidence and the need for prospective and randomized trials was also propounded by this review.
Giant congenital melanocytic nevus (garment nevus) is a kind of congenital malformation of neural crest cells with size greater than 20 cm. Malignant melanoma may develop in 2-31% of these lesions. The objective of this paper is to present a unique case of giant nevus which is rare. [Int J Res Med Sci 2013; 1(3.000): 317-319
Purpose To compare the clinical and radiological outcomes in patients with congenital scoliosis (CS) and tethered cord syndrome (TCS) undergoing deformity correction with (NI group) versus without (NNI group) prior neurosurgical intervention aimed at detethering the cord. Methods A systematic review and meta-analysis were performed. The databases PubMed, Embase and Google Scholar were searched until March 2020. Inclusion criteria was studied describing performance of deformity correction and fusion surgery for congenital scoliosis with tethered cord syndrome with or without prior detethering procedure. Studies describing growth sparing procedures or congenital scoliosis associated with non-tethering pathologies such as syrinx were excluded. Case reports and series with less than 10 subjects were also excluded. NIH quality assessment tool was used for assessing quality of individual study. Results Sixteen studies were included for analysis of which eight were found to be retrospective case series (level IV evidence) and retrospective case-control studies (level III evidence) each. Overall proportional meta-analysis found no significant difference in correction rate, operative duration, blood loss or complication rate between the NI and NNI groups. However, subgroup analysis performed after inclusion of only level III evidence studies revealed significantly lesser operative duration and blood loss with comparable correction and complication rate in NNI group. Conclusion Deformity correction and fusion surgery may be performed safely and effectively in CS with TCS patients without the need of a prior detethering procedure.
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