The use of pedicle screws has greatly improved the outcome of spinal fusion. However, each surgical solution for spinal fixation and fusion has its own structural and biomechanical characteristics. Therefore, it is important to select the correct endograft and technique for each case. Spinal fusion is a means to achieve a solid bony fusion as the ultimate goal. The purpose of fixed spinal fusion is to: 1. support the spine (re-establish clinical stability of the spine) when the structural integrity of the spine is severely compromised (e.g., vertebral fractures, tumor or tuberculosis disruption); 2. maintain the physiological curvature of the spine after mechanical correction of the spine (scoliosis, kyphosis and post-osteotomy); 3. prevent further aggravation of spinal deformity (scoliosis, kyphosis and vertebral slippage) 4. relieving or eliminating pain by immobilizing an area of the spine (reducing abnormal movement between segments of the spine).