| Section oneBackground and objectiveAnimal model of scoliosis plays an important role in scoliosis research, especially in the research of etiology. Bipedal rat is an ideal animal model in researching scoliosis. Procedures of the operation consist of denervation of the forelimbs, thoroughly dissection of the erector muscle of the spine, and tethering the ribs on the right side using size4sutures. However, high mortality (9.6%) accompanies current surgical procedures leading to a high rate of failure. In this study, modified procedures would be inspected.MethodsOperation of denervation in upper limbs and tethering ribs on the right side using4-0non-invasive suture without dissection of the erector muscle of spine was carried out in15rats.ResultsNo complications were observed in the surgical procedures, and no rat died during or after the operation.ConclusionsThe mortality of the operation declined to zero by reservation of the erector muscle of spine and tethering ribs on the right side using4-0non-invasive suture. Section twoBackground and objectiveScoliosis is still a disputed subject for the unknown etiology and unpredictable course. The factors can be divided into two major aspects-the biological factors and biomechanical factors. Both of the factors are suspected to be associated with the initiation and development of scoliosis. The biological factors are mainly focus on melatonin, calmodulin, estrogen, and growth hormones. However, controversy is present. The biomechanical factor has been regarded as the key factor.’Vicious cycle’has assumed that asymmetric loading would accelerate scoliosis. If we could change the status of asymmetric loading, scoliosis would have been prevented. Since now, the status of asymmetric loading can only be analyzed by Cobb angle and the locations of apical vertebra and end vertebrae, which is a retrospective method. The trabecular microarchitecture of the vertebra would be a potential marker to predict the distribution of biomechanics along with the development of iconography according to Wolffs law.MethodsBipedal rat models of scoliosis were established by tethering T5-6and T10-12ribs and denervation of the forelimb nerves. X-ray images of the entire spine were taken3weeks after the operation. Then micro-CT scans were carried out. After the raw images were reconstructed from projection images, microarchitecture parameters was calculated from binarisation images based on raw images following by a comparison between left side and right side. The results would be matched with the distribution of biomechanics on the spine to find out any potential micro architectural parameter that can best predict the distribution of biomechanics.Results1. The difference of percent bone volume (BV/TV) between left side and right side in apical vertebra is much more significant than that in other vertebrae;2. The difference of BV/TV between left side and right side is descending from the apical vertebra to end vertebrae;3. BV/TV has no difference between left side and right side in vertebra under symmetric loading;4. BV/TV is sensitive enough to explore the symmetry of loading.ConclusionsBV/TV of vertebral trabecular bone is correlated with the distribution of biomechanics, which can be used to predict the development of scoliosis or the status of decompensation after the operation in prophase. |
