การศึกษาทางชีวกลศาสตร์ของ interspinous distractive device ชนิดใหม่ที่คิดค้นขึ้นโดยเป็นการศึกษาในอาจารย์ใหญ่ / วีรศักดิ์ สิงหถนัดกิจ = The biomechanical study of a new interspinous distractive device (cadaveric study) / Weerasak Singhatanadgige
Background context: Lumbar fusion has been associated with inconsistent clinical outcomes and adjacent segment degeneration. Interspinous distractive device have been developed to stabilize painful diseased lumbar motion segments while avoiding fusion. The new interspinous distractive device was developed and tested biomechanically. Purpose: We analyzed the effects of the new interspinous distractive device on the biomechanical response of the lumbar spine in flexion-extension, lateral bending, after facetectomy and discectomy; the clinical situations in which its use might be considered. Study design/setting: experimental study. Methods: A biomechanical experimental study was performed using whole lumbar spine specimens (L1-L5). Surgical interventions were simulated at the L3–L4 level, and motions were measured at the operated and adjacent segments.The lumbar spines were subjected to load in flexion-extension (10 degree), lateral bending (10 degree).The specimens were tested under the following conditions: 1) intact; 2) after unilateral facetectomy and discectomy at L3–L4; and 3) #2 with Interspinous device. 4) #2 with fusion L3-4. The angular motion values at the operated and adjacent segments were analyzed. Result: Unilateral facetectomy and discectomy increased L3-L4 angular motion (Flexion,extension and bending) . Insertion of the interspinous device in L3-4 unstable specimen restored the increase all angular motion (flexion 5.50 to 2.16 degree, Extesion 4.25 to 1.41 degree, Flexion-Extension range 9.75 to 3.58 degree, bending 3.75 to 2.66 degree) without the effect of increase motion of adjacent Level ( L2-3, L4-5). Conclusions: The interspinous device is effective in stabilizing the unstable segment, reducing the increased segmental flexion-extension and bending motions observed after Unilateral facetectomy and discectomy.
