Li Xiao-Hui, Song Yue-Ming, Duan Hong
Department of Orthopaedics, Tianjin Hospital, Tianjin, China.
Department of Orthopaedics, West China Hospital, Sichuan University, Chengdu, China.
Orthop Surg. 2015 Aug;7(3):266-72. doi: 10.1111/os.12192.
To compare the characteristics of inter body fusion after using an established poly (D, L-lactic acid) (PDLLA) cage, a titanium cage or autologous tricortical iliac crest graft in a goat cervical spine model in vivo.
Twenty-four goats were assigned to three groups: PDLLA cage group (n = 8), titanium alloy cage group (n = 8) and autologous iliac bone group (n = 8), and underwent C3-4 discectomy and fusion with the allocated procedure. Radiography was performed pre- and post-operatively and after 1, 2, 4, 8 and 12 weeks and disc space height (DSH), intervertebral angle (IVA), and lordosis angle (LA) measured at these time points. After 12 weeks, the goats were killed and fusion sites removed. Biomechanical testing was performed in flexion, extension, axial rotation, and lateral bending to determine the stiffness and range of motion (ROM). All specimens were also assessed histomorphologically.
The IVA of PDLLA cage four weeks postoperatively and DSH eight and twelve weeks postoperatively were significantly greater than that of autologous iliac bone graft (P < 0.05). The LA values did not differ significantly between groups. The stiffness of both types of cages for axial rotation and lateral bending, and ROM for every movement, were significantly greater than that of the autologous iliac bone graft group (P < 0.05). PDLLA and titanium cages did not differ significantly (P > 0.05). Radiographic and histomorphological assessment showed better fusion in the cage than the autologous bone groups.
The PDLLA cage can provide good intervertebral distract ability and enough biomechanical stability for cervical fusion.
在山羊颈椎体内模型中比较使用已有的聚（D，L-乳酸）（PDLLA）椎间融合器、钛椎间融合器或自体三面皮质髂嵴移植骨后椎间融合的特征。
将24只山羊分为三组：PDLLA椎间融合器组（n = 8）、钛合金椎间融合器组（n = 8）和自体髂骨组（n = 8），并采用分配的手术方法进行C3-4椎间盘切除及融合术。在术前、术后以及术后1、2、4、8和12周进行X线检查，并在这些时间点测量椎间隙高度（DSH）、椎间角度（IVA）和前凸角（LA）。12周后，处死山羊并取出融合部位。进行前屈、后伸、轴向旋转和侧方弯曲的生物力学测试，以确定刚度和活动范围（ROM）。所有标本也进行组织形态学评估。
PDLLA椎间融合器组术后4周的IVA以及术后8周和12周的DSH均显著大于自体髂骨移植组（P < 0.05）。各组间LA值差异无统计学意义。两种椎间融合器在轴向旋转和侧方弯曲时的刚度以及每个动作的ROM均显著大于自体髂骨移植组（P < 0.05）。PDLLA椎间融合器和钛椎间融合器之间差异无统计学意义（P > 0.05）。影像学和组织形态学评估显示椎间融合器组比自体骨组融合更好。
PDLLA椎间融合器可为颈椎融合提供良好的椎间撑开能力和足够的生物力学稳定性。
