Toth J M, Seim H B, Schwardt J D, Humphrey W B, Wallskog J A, Turner A S
Department of Orthopaedic Surgery, Medical College of Wisconsin, Milwaukee, WI 53226-0099, USA.
Spine (Phila Pa 1976). 2000 Oct 15;25(20):2580-7. doi: 10.1097/00007632-200010150-00007.
A randomized experimental evaluation of direct current stimulation in a validated animal model with an experimental control group, using blinded radiographic, biomechanical, histologic, and statistical measures.
To evaluate the efficacy of the adjunctive use of direct current stimulation on the fusion rate and speed of healing of titanium interbody fusion cages packed with autograft in a sheep lumbar interbody fusion model.
Titanium lumbar interbody spinal fusion cages have been reported to be 90% effective for single-level lumbar interbody fusion. However, fusion rates are reported to be between 70% and 80% in patients with multilevel fusions or with risk factors such as obesity, tobacco use, or metabolic disorders. The authors hypothesized that direct current stimulation would increase the fusion rate of titanium interbody fusion cages packed with autograft in a sheep lumbar interbody fusion model.
Twenty-two sheep underwent lumbar discectomy and fusion at L4-L5 with an 11- x 20-mm Bagby and Kuslich (BAK) cage packed with autograft. Seven sheep received a BAK cage and no current. Seven sheep had a cage and a 40-microA current applied with a direct current stimulator. Eight sheep had a BAK cage and a 100-microA current applied. All sheep were killed 4 months after surgery. The efficacy of electrical stimulation in promoting interbody fusion was assessed by performing radiographic, biomechanical, and histologic analyses in a blinded fashion.
The histologic fusion rate increased as the direct current dose increased from 0 microA to 40 microA to 100 microA (P < 0.009). Histologically, all animals in the 100-microA group had fusions in both the right and left sides of the cage. Direct current stimulation had a significant effect on increasing the stiffness of the treated motion segment in right lateral bending (P < 0.120), left lateral bending (P < 0.017), right axial rotation (P < 0.004), left axial rotation (P < 0.073), extension (P < 0.078), and flexion (P < 0.029) over nonstimulated levels.
Direct current stimulation increased the histologic and biomechanical fusion rate and the speed of healing of lumbar interbody spinal fusion cages in an ovine model at 4 months.
在一个经过验证的动物模型中进行随机实验评估，设立实验对照组，采用盲法影像学、生物力学、组织学及统计学测量方法。
在绵羊腰椎椎间融合模型中，评估直流电刺激辅助使用对填充自体骨的钛制椎间融合器融合率及愈合速度的疗效。
据报道，钛制腰椎椎间融合器用于单节段腰椎椎间融合的有效率为90%。然而，据报道，多节段融合患者或存在肥胖、吸烟或代谢紊乱等危险因素的患者，融合率在70%至80%之间。作者推测，在绵羊腰椎椎间融合模型中，直流电刺激会提高填充自体骨的钛制椎间融合器的融合率。
22只绵羊接受L4-L5节段腰椎间盘切除术并使用填充自体骨的11×20毫米Bagby和Kuslich（BAK）融合器进行融合。7只绵羊接受BAK融合器且不施加电流。7只绵羊植入融合器并通过直流刺激器施加40微安电流。8只绵羊植入BAK融合器并施加100微安电流。所有绵羊在术后4个月处死。通过盲法进行影像学、生物力学和组织学分析来评估电刺激促进椎间融合的疗效。
随着直流电剂量从0微安增加到40微安再增加到100微安，组织学融合率升高（P < 0.009）。组织学上，100微安组的所有动物在融合器的左右两侧均实现融合。与未刺激组相比，直流电刺激对增加治疗节段在右侧侧弯（P < 0.120）、左侧侧弯（P < 0.017）、右侧轴向旋转（P < 0.004）、左侧轴向旋转（P < 0.073）、伸展（P < 0.078）和屈曲（P < 0.029）时的刚度有显著影响。
在绵羊模型中，4个月时直流电刺激提高了腰椎椎间融合器的组织学和生物力学融合率以及愈合速度。
