Biomechanical characteristics of a novel interspinous distraction fusion device BacFuse for the repair of lumbar degenerative disease / 中国组织工程研究

ABSTRACT

BACKGROUND:Interspinous distraction fusion device BacFuse was used for the management of lumbar degenerative disease and obtained good clinical efficacy in recent years.However,the related biomechanical study was lacking. OBJECTIVE:To explore the related biomechanical characteristics of BacFuse,a novel interspinous distraction fusion device,which was used in lumbar degenerative disease. METHODS:After constructing the goat spinal models(L1-L6),they were grouped into four groups based on different simulated surgeries:the control group,the BacFuse group(L3/4),the screw-rod fixation group(L3/4)and the Topping-off group(L3/4 screw-rod fixation + L2/3 BacFuse fixation).The goat lumbar spine surgical model was assembled into a biomechanical testing system.A biomechanical machine was used for mechanical loading,simulating lumbar spine movement of flexion,extension,lateral flexion and rotation with a 4 Nm moment.A visual tracking system was used for positioning and capturing.Finally,mechanical and optical calibration was completed to calculate the range of motion of the L2/3,L3/4 and L4/5 segments. RESULTS AND CONCLUSION:(1)Compared with the control group,the range of motion of the L3/4 segment in the BacFuse group decreased 27.27%,70%,38.1%and 23.08%in the flexion,extension,lateral bending and rotation directions,respectively(P<0.05).The range of motion of L3/4 segment in the screw-rod fixation group decreased 72.73%,80%,71.43%and 73.08%in the flexion,extension,lateral bending and rotation directions,respectively(P<0.05).(2)Compared with the control group,the range of motion of the adjacent segment L2/3 increased by 33.33%,25%and 23.81%in the extension,lateral bending and rotation directions,respectively in the BacFuse group(P<0.05),with no significant change in flexion.In the screw-rod fixation group,there was a 50%,44.44%,50%and 58.96%increase in the adjacent segment L2/3 in the flexion,extension,lateral calibration and rotation directions,respectively(P<0.05).(3)Compared with the control group,the BacFuse group showed an increase in range of motion in proximal segment L4/5 in the extension and rotation directions by 27.3%and 17.39%(P<0.05)respectively,with no significant change in flexion or lateral bending.In the screw-rob fixation group,the proximal segment L4/5 demonstrated 38.89%,22.73%and 26.09%(P<0.05)increases in range of motion in the flexion,extension and rotation directions,respectively,with no significant change in lateral bending.(4)In the Topping-off group,the range of motion of L2/3 was reduced by 37.04%,73.08%,56.67%and 38.46%in flexion,extension,lateral flexion and rotation,respectively,compared to the screw-rob fixation group(P<0.05).Compared with the screw-rob fixation group,the Topping-off group showed a 20%reduction in the range of motion of the L4/5 in the flexion direction(P<0.05),with no significant differences seen in extension,lateral bending and rotation.(5)It is concluded that the interspinous distraction fusion device BacFuse significantly reduces the range of motion of the implanted segment and provides some stability.It still retains more mobility and reduces the impact on the adjacent segment compared to screw-rob fixation,while the Topping-off tip,which can be used for intervertebral fusion fixation,significantly reduces the range of motion of the adjacent segment and reduces the risk of adjacent segment degeneration.