Comparison of nano-hydroxyapatite/polyamide 66 bioactive support and autologous iliac bone in bone grafting and fusion for elderly patients with lumbar tuberculosis

March 18, 2022

Objective:

To investigate the safety of nano-hydroxyapatite/polyamide 66 (n-HA/PA66) bioactive support in bone grafting and fusion for elderly patients with lumbar tuberculosis, and to analyze its effectiveness and advantages by comparing with autologous iliac bone grafting.

Methods:

A retrospective analysis was performed on 48 elderly patients with lumbar tuberculosis who met the selection criteria between January 2017 and January 2020. The patients all underwent one-stage posterior pedicle screw internal fixation combined with anterior lesion removal and bone grafting and fusion, of which 23 cases applied n-HA/PA66 bioactive support+allogeneic bone graft (n-HA/PA66 group) and 25 cases applied autologous iliac bone graft (autologous iliac bone group). There was no significant difference between the two groups in gender, age, bone density, disease duration, lesion segment, and preoperative pain visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, and Cobb angle ( P>0.05). The operation time, intraoperative blood loss, and postoperative complications, as well as the VAS score, JOA score, American Spinal Injury Association (ASIA) spinal cord injury grading, Cobb angle, and bone fusion were recorded and compared between the two groups.

Results:

The operations were completed successfully in both groups. n-HA/PA66 group had significantly less operation time and intraoperative blood loss than the autologous iliac bone group ( P<0.05). All patients were followed up 12-24 months, with an average of 15.7 months. And the difference in follow-up time between the two groups was not significant ( P>0.05). Postoperative complications occurred in 3 cases (13%) in the n-HA/PA66 group and 10 cases (40%) in the autologous iliac group, and the difference in the incidence of complications between the two groups was significant ( χ ²=4.408, P=0.036). The postoperative VAS scores and JOA scores significantly improved when compared with the preoperative scores in both groups ( P<0.05), and the difference was significant ( P<0.05) between 2 weeks after operation and the last follow-up. The difference in VAS score at 2 weeks after operation was significant between the two groups ( P<0.05), and there was no significant difference ( P>0.05) at the other time points. At last follow-up, according to the ASIA grading, the effective improvement rate was 86% (18/21) in the n-HA/PA66 group and 90% (18/20) in the autologous iliac group, with no significant difference ( χ ²=0.176, P=0.675). Imaging review showed that grade Ⅰ bony fusion was obtained in both groups, and the fusion time of bone graft in the n-HA/PA66 group was significantly longer than that in the autologous iliac bone group ( P<0.05). There was no significant difference in the Cobb angle at each time point between the two groups ( P>0.05). No recurrence of tuberculosis, loosening or fracture of the internal fixator, or displacement of the bone graft was observed during follow-up.

Conclusion:

In elderly patients with lumbar spine tuberculosis, the n-HA/PA66 bioactive support combined with allogeneic bone graft can effectively restore and maintain the fusion segment height and physiological curvature of the lumbar spine, and the fusion rate of bone graft is similar to that of autologous iliac bone, which can achieve better effectiveness.

目的:

探讨老年腰椎结核植骨融合术中应用纳米羟基磷灰石/聚酰胺66（nano-hydroxyapatite/polyamide 66，n-HA/PA66）生物活性支撑体的安全性，通过与自体髂骨植骨相比，分析其疗效及优势。.

方法:

回顾性分析2017年1月—2020年1月符合选择标准的48例老年腰椎结核患者。患者均接受一期后路椎弓根螺钉内固定联合前路病灶清除植骨融合术，其中，23例术中应用n-HA/PA66生物活性支撑体+同种异体骨植骨（n-HA/PA66组），25例应用自体髂骨植骨（自体髂骨组）。两组患者性别、年龄、骨密度、病程、病变累及范围以及术前疼痛视觉模拟评分（VAS）、日本骨科协会（JOA）评分、后凸Cobb角等一般资料比较，差异均无统计学意义（ P>0.05）。记录并比较两组手术时间、术中出血量、术后并发症发生情况，以及VAS评分、JOA评分、美国脊髓损伤协会（ASIA）脊髓损伤分级、后凸Cobb角、植骨融合情况。.

结果:

两组手术均顺利完成。n-HA/PA66组手术时间及术中出血量均小于自体髂骨组（ P<0.05）。患者均获随访，随访时间12～24个月，平均15.7个月，两组随访时间比较差异无统计学意义（ P>0.05）。术后n-HA/PA66组3例（13%）、自体髂骨组10例（40%）发生并发症，两组并发症发生率比较差异有统计学意义（ χ ²=4.408， P=0.036）。两组内术后VAS评分、JOA评分均较术前改善（ P<0.05），末次随访时与术后2周比较差异亦有统计学意义（ P<0.05）；两组间术后2周VAS评分差异有统计学意义（ P<0.05），其余时间点上述指标比较差异均无统计学意义（ P>0.05）。末次随访时，n-HA/PA66组ASIA分级有效改善率为 86%（18/21），自体髂骨组为 90%（18/20），差异无统计学意义（ χ ²=0.176， P=0.675）。影像学复查示两组患者均获得Ⅰ级骨性融合，n-HA/PA66组植骨融合时间长于自体髂骨组（ P<0.05）。两组组间术后各时间点后凸Cobb角比较，差异均无统计学意义（ P>0.05）。随访期间，患者均无结核复发、内固定物松动及断裂、植骨材料移位等情况发生。.