Luo T David, Marquez-Lara Alejandro, Zabarsky Zachary K, Vines Jeremy B, Mowry Katie C, Jinnah Alexander H, Ma Xue, Berwick Benjamin W, Willey Jeffrey S, Li Zhongyu, Smith Thomas L, O'Gara Tadhg J
1 Department of Orthopaedic Surgery, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA.
2 Organogenesis Surgical and Sports Medicine, Birmingham, AL, USA.
J Orthop Surg (Hong Kong). 2018 May-Aug;26(3):2309499018792715. doi: 10.1177/2309499018792715.
Various animal models have been proposed to mimic the pathophysiologic process of intervertebral disc degeneration, a leading cause of back pain. The purpose of this study is to describe a minimally invasive technique via percutaneous needle puncture of the annulus fibrosus in New Zealand white rabbits.
Under fluoroscopic guidance, an 18-gauge spinal needle was inserted 2 cm lateral to the midline spinous process. The needle was slowly advanced at approximately 45° angle until it was adjacent to the L5/L6 disc space. Lateral and anteroposterior views were used to verify correct needle position before advancing into the nucleus pulposus. The rabbits underwent weekly X-rays for 4 weeks to assess disc height index. MRI T2 relaxation was evaluated at week four to assess morphological changes. Discs were histologically graded on a 12-point scale to assess degeneration and compared to discs obtained from uninjured rabbits.
There were no complications associated with the percutaneous needle puncture procedure. All animals survived the duration of the experiment. Four weeks after injury, the disc height had progressively narrowed to approximately 50% of baseline. MRI assessment at the 4-week time point demonstrated a mean T2 relaxation time at the L5/L6 level that was 20.9% of the T2 relaxation time at the uninjured L4/L5 disc level ( p < 0.001). Histological analysis demonstrated lamellar disorganization of the annulus and decreased cellularity and proteoglycan content within the injured nucleus compared to uninjured control discs.
The present study demonstrated a reliable technique of inducing an annular tear via a percutaneous needle puncture. Compared to open surgical approaches, the percutaneous model produces similar progressive disc degeneration while minimizing harm to the animal subjects.
The present study establishes a technique for the introduction of novel therapeutic agents to treat disc degeneration that may translate to future clinical trials.
已提出多种动物模型来模拟椎间盘退变的病理生理过程，而椎间盘退变是背痛的主要原因。本研究的目的是描述一种通过经皮针刺新西兰白兔纤维环的微创技术。
在荧光镜引导下，将一根18号脊椎穿刺针插入棘突中线外侧2厘米处。针以约45°角缓慢推进，直到靠近L5/L6椎间盘间隙。在推进到髓核之前，使用侧位和前后位视图来确认针的正确位置。对兔子进行为期4周的每周一次X线检查，以评估椎间盘高度指数。在第4周评估MRI T2弛豫，以评估形态学变化。对椎间盘进行12分制的组织学分级，以评估退变情况，并与从未受伤兔子获得的椎间盘进行比较。
经皮针刺操作未出现并发症。所有动物在实验期间均存活。损伤后4周，椎间盘高度逐渐变窄至基线的约50%。在4周时间点的MRI评估显示，L5/L6水平的平均T2弛豫时间为未受伤的L4/L5椎间盘水平T2弛豫时间的20.9%（p < 0.001）。组织学分析表明，与未受伤的对照椎间盘相比，损伤的髓核内纤维环出现层状紊乱，细胞数量减少，蛋白聚糖含量降低。
本研究证明了一种通过经皮针刺诱导环形撕裂的可靠技术。与开放手术方法相比，经皮模型产生类似的进行性椎间盘退变，同时将对动物受试者的伤害降至最低。
本研究建立了一种引入新型治疗药物治疗椎间盘退变的技术，这可能转化为未来的临床试验。
