Objective: To analyze the technical notes, effectiveness, and current issues of real-time three-dimensional CT navigation-guided full-endoscopic lumbar interbody fusion.
Methods: Between April 2020 and October 2021, a total of 27 patients received real-time three-dimensional CT navigation-guided full-endoscopic lumbar interbody fusion. There were 18 males and 9 females with an average age of 63.2 years (range, 48-84 years). There were 6 cases of lumbar spinal stenosis, 1 case of lumbar instability, 9 cases of lumbar spinal stenosis with instability, 3 cases of degenerative spondylolisthesis, 6 cases of isthmus spondylolisthesis, and 2 cases of recurrent lumbar disc herniation. All patients showed neurological symptoms before operation (ipsilateral symptom for 15 cases and bilateral symptom for 12 cases). The symptom duration was 1-300 months (median, 24 months). The operations were performed via transforaminal approach in 8 cases, trans-facet joint approach in 18 cases, and combined approaches in 1 case. A total of 32 levels were fused, including 23 single-level cases, 3 two-level cases, and 1 three-level case. Lumbar fusion segment was L 2, 3 in 1 case, L 3, 4 in 4 cases, L 4, 5 in 20 cases, and L 5, S 1 in 7 cases. The operation time, intraoperative estimated blood loss (IEBL), and perioperative complications were recorded. The improvement of intervertebral space height at fusion level was measured, and the accuracy of percutaneous pedicle screw (PPS) and Cage placement was also evaluated based on CT images performed at 1 week postoperatively. Visual analogue scale (VAS) score for both low back pain and leg pain, Japanese Orthopaedic Association (JOA) score, and Oswestry disability index (ODI) were evaluated before operation, at 1 week postoperatively, and at last follow-up. Satisfaction to effectivenss were assessed by patients using modified MacNab criteria at last follow-up.
Results: The operation time was ranged from 255 to 805 minutes (mean, 424.9 minutes). IEBL was 150-290 mL (mean, 219.3 mL). All patients received follow-up with the duration from 4 to 22 months (mean, 12.4 months). At 1 week postoperatively and last follow-up, VAS scores of low back pain and leg pain, JOA score, and ODI were significantly improved when compared with those before operation ( P<0.05). At last follow-up, the clinical indicators were similar in comparison with those at 1 week postoperatively ( P>0.05). There were 26 patients and 1 patient who respectively ranked excellent and mild in terms of effectiveness according to the modified MacNab criteria, with the excellent and good rate of 96.3%. There was 1 patient who suffered from incomplete injury of L 5 nerve root and partial neurological function recovered after 3-month conservative treatments. There were 118 implanted PPSs, and 116 of them were implanted under navigation. There were 33 Cages that were implanted under navigation. The accuracy of PPS and Cage placement was 99.1% and 97.0% respectively based on CT performed at 1 week postoperatively. The postoperative intervertebral space height was significantly increased in comparison with that before operation ( P<0.05). During follow-up, mild Cage subsidence was observed in 1 patient, whereas no fixation loosing was found.
Conclusion: Real-time three-dimensional CT navigation-guided full-endoscopic lumbar interbody fusion has great safety and effectiveness with satisfactory preliminary clinical results. Design and further improvement of surgical equipment and instruments are expected to resolve the current technical difficulties.
目的: 探讨实时三维CT导航引导脊柱内镜下腰椎椎间融合术的疗效，总结手术技术要点及存在问题。.
方法: 2020年4月—2021年10月，27例腰椎疾病患者接受实时三维CT导航引导脊柱内镜下腰椎椎间融合术。男18例，女9例；年龄48～84岁，平均63.2岁。疾病类型：单纯腰椎管狭窄症6例，单纯腰椎失稳症1例，腰椎管狭窄合并腰椎失稳症9例，退行性腰椎滑脱症3例，峡部裂性腰椎滑脱症6例，复发性腰椎间盘突出症2例。患者均存在下肢神经症状，其中单侧15例、双侧12例。病程1～300个月，中位数24个月。术中经椎间孔入路8例、经关节突入路18例、联合入路1例；共32个节段融合，其中单节段融合23例、双节段融合3例、三节段融合1例；L 2、3 1例、L 3、4 4例、L 4、5 20例及L 5、S 1 7例。记录手术时间、术中估计失血量（intraoperative estimated blood loss，IEBL）及围术期并发症；术后1周CT测量手术节段椎间隙高度改善情况，评价经皮椎弓根螺钉及Cage植入的准确性；评估术前及术后1周、末次随访时腰腿部疼痛视觉模拟评分（VAS）、日本骨科学会（JOA）评分、Oswestry功能障碍指数（ODI），末次随访时采用改良MacNab标准评价患者对手术疗效的满意度。.
结果: 手术时间255～805 min，平均424.9 min；IEBL为150～290 mL，平均219.3 mL。患者均获随访，随访时间4～22个月，平均12.4个月。术后1周及末次随访时，患者腰痛VAS评分、腿痛VAS评分、ODI均较术前下降，JOA评分升高，差异有统计学意义（ P<0.05）；末次随访时与术后1周比较差异无统计学意义（ P>0.05）。末次随访时，根据改良MacNab标准，患者对疗效满意度达优26例、中1例，优良率96.3%。1例术中L 5神经根束支部分损伤，对症治疗3个月后部分恢复。术中共植入118枚经皮椎弓根螺钉（其中116枚经导航引导下植入）、33枚Cage（均经导航引导下植入），术后1周复查CT评判导航引导下植钉准确率99.1%、Cage植入准确率97.0%，手术节段椎间隙高度较术前提升（ P<0.05）。1例患者随访期间Cage出现轻度下沉，但所有患者内固定物未见明显松动。.
结论: 实时三维CT导航引导脊柱内镜下腰椎椎间融合术安全可靠、初步应用疗效满意，存在的技术难点问题有待工具设备进一步研发与优化加以解决。.
Keywords: Real-time navigation; lumbar interbody fusion; spine endoscopic surgery; three-dimensional CT; transforaminal apporoach.