چكيده به لاتين
Vertebral compression fractures (VCFs) are a common cause of back pain and disability and are usually osteoporotic in nature.Vertebroplasty is an effective treatment for osteoporotic vertebral fractures, which are one of the most common fractures associated with osteoporosis. Therapy aims to adequately control pain and allow early mobilisation and return of function while preventing additional fractures. New osteoporotic secondary vertebral compression fractures (SVCF)is one of the serious complications of vertebroplasty, and it is important to investigate the risk factors for such SVCF, Another important complication of vertebroplasty is bone cement leakage. possible risk factors screened for were age, gender, regional distribution, outdoor activity (ODA), bone mineral density (BMD), surgical methods (unilateral or bilateral), bone cement dose, bone cement leakage, chronic disease history, postoperative anti-osteoporosis treatment, and level of preoperative osteoporotic vertebral compression fracture(OVCF). In this project, vertebroplasty was performed on a three vertebral model consisting of the second, third, and fourth lumbar vertebrae. The spine model is examined in 5 standing positions, flexion, extension, lateral bending and torsion. Bone cement with three different volumes was injected into the third lumbar vertebra to fill 30%, 50% and 70% of the cancellous bone of the third lumbar vertebra. Finite element static analysis is performed under 5 conditions: normal, osteoporosis and vertebral augmentation with bone cement 1800, 500 and 150 MPa. The maximum von Mises stress in these 5 conditions are examined and compared in different parts of the model. The best modulus of elasticity and injection volume of bone cement is obtained based on the proximity of the maximum von-Mises stress to the maximum von-Mises stress of the model in the state of osteoporosis. Finally, it was concluded; When 30% of the cancellous bone of the third lumbar vertebra is filled with bone cement; The maximum von Mises stress is obtained close to the maximum von Mises stress in the state of osteoporosis. Also, for the elasticity modulus, the result of the proximity of the maximum von Mises stress to the maximum von Mises stress of the osteoporosis model, in different parts of the model And it is different in different states of standing, flexion, extension, etc., but in general, bone cement with a modulus of elasticity of 150 MPa has the closest maximum Von Mises stress to the model in the state of osteoporosis.
