Objective: To compare and analyze the feasibility of autologous facet joint bone block as an alternative to polyetheretherketone (PEEK) cage in lumbar intervertebral fusion surgery for patients with osteoporosis.
Methods: From December 2018 to June 2021, the case data of patients with osteoporosis (T value ≤ -2.5 on dual energy X-ray bone density) who underwent posterior lumbar interbody fusion in the Fourth Medical Center, Chinese PLA General Hospital were retrospectively reviewed. All the cases were followed up for no less than 12 months and were divided into two groups according to the differences of interbody fusion materials: the autologous facet joint bone block group (autogenous bone group) and the PEEK cage group (PEEK group). The general data [such as age, gender, body mass index (BMI), primary diagnosis, distribution of fusion segments, bone mineral density of lumbar (BMD), incidence of preoperative complications], the perioperative data (such as duration of operation, intraoperative blood loss, postoperative drainage, perioperative allogeneic blood transfusion rate), and the incidence of postoperative complications were compared between the two groups. Imaging parameters (disc height, lumbar lordosis angle, segment lordosis angle, segmental lordosis angle, disc height improvement rate, and fusion rate) and lumbar functional scores [visual analogue scale (VAS), Oswestry disability index (ODI), Japanese Orthopedics Association (JOA) score for lower back pain] were compared to evaluate the clinical efficacy between the kinds of intervertebral fusion materials 1 week, 3 months and 6 months postoperative and at the last follow-up.
Results: A total of 118 patients were enrolled, including 68 cases in the autogenous bone group and 50 cases in the PEEK group, there were no statistical differences in age, gender, BMI, primary diagnosis, distribution of fusion segments, BMD, incidence of preoperative complications, duration of operation, intraoperative blood loss, postoperative drainage, perioperative allogeneic blood transfusion rate, incidence of postoperative complications, all the preoperative imaging parameters and all the lumbar function scores between the two groups (P>0.05). Postoperative superficial surgical site infections occurred in 3 patients in the autogenous bone group and 2 patients in the PEEK group. At the last follow-up, 3 cases of intervertebral graft collapse occurred in the autogenous bone group and 5 cases in the PEEK group, 1 case of graft subsidence in the autogenous bone group and 1 case in the PEEK group. All the imaging parameters showed significant differences between postoperation and preoperation (P < 0.05), and all the imaging parameters showed significant differences between 1 week and 3 months postoperative in both groups (P < 0.05). The height, angle of fusion gap in the autogenous bone group were lower than those in the PEEK group 1 week postoperatively (P < 0.05), and the fusion gap height improvement rate in the autogenous bone group was lower than that in the PEEK group (P < 0.05). The cases in both groups started to show final fusion 3 months after surgery, and the fusion rate in the autogenous bone group was 75% 6 months postoperatively, which was significantly higher than the rate of 56% in the PEEK group (P < 0.05), and there was no statistically significant difference in the final fusion rate between the two groups (P>0.05). The ODI, the postoperative VAS score was significantly lower than that in preoperation, while the postoperative JOA score was significantly higher than that in preoperation (P < 0.05). The ODI was lower while the JOA score was higher of the autogenous bone group than that of the PEEK group 6 months postoperatively (P < 0.05).
Conclusion: In osteoporosis patients, good interbody fusion rate and improvement of lumbar vertebral function can be obtained by using autologous facet joint bone block or PEEK cage, while the fusion rate and the improvement of lumbar function with autologous facet joint bone block are better than those with PEEK cage 6 months post-operatively. PEEK cage is superior to autologous facet joint bone block in intervertebral distraction and improvement of lumbar lordosis. Significant disc space subsidence occurred in osteoporotic patients within 3 months after lumbar interbody fusion, and the subsidence of PEEK cage was more obvious than that of autologous facet joint bone block.
目的: 比较骨质疏松患者腰椎椎间融合术中植入自体下关节突骨块或聚醚醚酮(polyetheretherketone, PEEK)椎间融合器的疗效, 评估自体下关节突骨块替代椎间融合器的可行性。
方法: 回顾性分析2018年12月至2021年6月在中国人民解放军总医院第四医学中心接受后路腰椎改良开窗减压、椎间植骨融合内固定术治疗且术前合并骨质疏松(双能X线骨密度T值≤-2.5)患者的病例资料, 随访时长不低于术后12个月。根据椎间融合材料的差异分为两组, 椎间植入自体下关节突骨块的患者纳入下关节突组, 植入PEEK椎间融合器的患者纳入PEEK组, 比较两组患者的一般资料(年龄、性别、体重指数、发病时长、主诊断及融合节段分布、腰椎骨密度、术前合并症的发病率)、围手术期资料(手术时长、术中失血量、术后引流量、围术期异体血输血率)及术后并发症的差异, 同时对比两组术前、术后1周、术后3个月、术后6个月及末次随访时的影像学参数(椎间隙高度、腰椎前凸角、节段前凸角、融合间隙角、椎间隙高度改善率、融合率)以及腰椎功能评分[视觉模拟评分(visual analogue scale, VAS)、Oswestry功能障碍指数(Oswestry disability index, ODI)、下腰痛日本骨科协会(Japanese Orthopedics Association, JOA)评分], 评价两种椎间融合材料的临床疗效。
结果: 共纳入118例患者, 其中下关节突组68例, PEEK组50例, 两组病例在年龄、性别、体重指数、发病时长、主诊断及融合节段分布、腰椎骨密度、术前合并症的发病率、术前各影像学参数及腰椎功能评分方面差异无统计学意义(P>0.05), 组间具有可比性。两组在手术时长、术中出血量、术后引流量、异体血输血率方面差异也无统计学意义(P>0.05)。术后下关节突组有3例浅表手术部位感染, PEEK组有2例; 末次随访时下关节突组有3例椎间移植物塌陷, PEEK组有5例; 下关节突组有1例移植物后退, PEEK组也有1例。各随访时间节点两组的椎间隙高度、腰椎前凸角、节段前凸角、融合间隙角均明显大于术前(P < 0.05), 但术后3个月与术后1周相比, 上述参数均明显下降(P < 0.05)。组间比较显示, 术后1周时下关节突组的椎间隙高度及融合间隙角小于PEEK组(P < 0.05), 椎间隙改善率小于PEEK组(P < 0.05)。两组病例自术后3个月开始出现椎间融合, 术后6个月时下关节突组的融合率为75%, 明显高于PEEK组的56%(P < 0.05), 但两组末次随访时的融合率差异无统计学意义(P>0.05)。腰椎功能评分的组内比较显示, 两组术后的腰痛VAS评分、ODI均明显低于术前(P < 0.05), JOA评分明显高于术前(P < 0.05);组间比较显示, 下关节突组术后6个月时的ODI更低, 而JOA评分更高(P < 0.05)。
结论: 骨质疏松患者腰椎椎间融合术中, 椎间植入自体下关节突骨块或PEEK椎间融合器均能获得良好的椎间融合率及腰椎功能改善, 但术后6个月时自体下关节突骨块的融合率及腰椎功能改善优于PEEK椎间融合器。PEEK椎间融合器在术后早期的椎间撑开及椎间隙前凸改善作用优于自体下关节突骨块。骨质疏松患者腰椎椎间融合术后3个月内会出现明显的椎间隙沉降, 椎间植入PEEK椎间融合器比自体下关节突骨块的沉降更为明显。
Keywords: Autologous facet joint; Bone transplantation; Lumbar vertebrae; Osteoporosis; Spinal fusion.