三维CT指导经皮内镜后外侧入路治疗胸椎间盘突出症建立良好的骨性通道

Three-dimensional CT analysis of the treatment of thoracic disc herniation by percutaneous endoscopic posterolateral approach: establishment of a good osseous channel

背景:经皮脊柱内镜技术治疗胸椎间盘突出症的国内外文献报道甚少,尚未对该技术的手术适应证、技术要点、技术局限性等进行深入阐述。目的:通过三维CT成像指导经皮脊柱内镜后外侧入路治疗胸椎间盘突出症。方法:纳入2017年8月至2020年3月滨州医学院附属医院收治的13例胸椎间盘突出症患者,行胸椎电子计算机断层扫描脊髓造影检查,重建胸椎三维CT图像。①测量下关节突外下缘与上关节突外侧缘交点(Y点)至硬脊膜外侧缘(a)、关节突关节内侧缘(b)、上位椎体下终板(c)、下位椎体上终板的距离(d),测量硬脊膜外侧缘至椎弓根根部内侧缘与椎体中线夹角(g),硬脊膜外侧缘至椎体后正中与椎体中线夹角(h)。于肩胛骨位置(T_(1/2)-T6/7)水平,横断面测量相应节段椎弓根根部内侧缘至肩胛骨内侧缘与椎体中线夹角(i)。在软件三维视图中,根据工作通道创建直径7.5 mm 3D圆柱体导板,观察导板到达椎弓根根部内侧缘通道经过的骨性结构,测量关节突关节缺损范围(j)。②13例患者均行经皮脊柱内镜后外侧入路胸椎间盘切除术治疗,采用目测类比评分、日本骨科协会(JOA)胸脊髓功能评分、Oswestry功能障碍指数及改良Mac Nab评估临床疗效。研究获得滨州医学院附属医院伦理委员会批准。结果与结论:①T_(2/3)-T10/11椎体间Y点至硬脊膜外侧缘的距离比较差异无显著性意义(P> 0.05),T_(1/2)-T10/11椎体间Y点至关节突关节内侧缘的距离比较差异无显著性意义(P> 0.05);②T_(1/2)椎体矢状面上Y点投影在椎间隙上方,其余节段矢状面上Y点投影在椎间隙水平;③T_(1/2)椎体hi,导板外展时被肩胛骨阻挡;④13例患者末次随访的目测类比评分、JOA胸脊髓功能评分与Oswestry功能障碍指数评分均较术前明显改善(P<0.05),改良Mac Nab术后优良率为92%;⑤由于T_(1/2)-T_(4/5)节段位置深在且被肩胛骨等阻挡,工作通道外展受限,经皮内镜后外侧路适用于旁中央型软性胸椎间盘突出症;在T5/6-T11/12节段,经皮脊柱内镜后外侧入路适用于各种类型、性质的胸椎间盘突出症(巨大型除外);⑥结果表明,Y点可作为内镜下骨性定位标志,在矢状面上其恒定投影在椎间隙水平(T_(1/2)除外);建立骨性通道需磨除各胸椎节段的骨性结构不同;经皮脊柱内镜后外侧入路治疗胸椎间盘突出症疗效显著、安全可行。

BACKGROUND:There are few domestic and foreign literature reports on the treatment of thoracic disc herniation by percutaneous endoscopy,and the operative indications,technical points and technical limitations of this technique have not been thoroughly expounded.OBJECTIVE:To guide the treatment of thoracic disc herniation by the percutaneous endoscopic posterolateral approach through three-dimensional CT imaging.METHODS:Thirteen patients with thoracic disc herniation admitted to the Affiliated Hospital of Binzhou Medical College from August 2017 to March 2020 were included.Thoracic computed tomography myelograhy examination was performed and three-dimensional CT images of thora cic vertebra were reconstructed.(1)Measu ring articular process under the lower edge and articular process on the lateral margin of inte rsection point(Y)to the late ral edge of dura mater(a),medial margin of articular process(b),lower endplate of upper vertebra(c),and distance of upper endplate of lower vertebra(d),angle between lateral margin of dura mater to medial margin of vertebral arch root and vertebral body centerline(g),angle between the late ral edge of dura mater to poste rior midline of the ve rtebral bodies and vertebral body centerline(h).At the level of the scapula(T1/2-T6/7),the angle between the medial edge of the vertebral arch root to the medial edge of the scapula and the midline of the vertebral body was measured in cross section(i).In the 3D view of the software,a 7.5-mm 3D cylindrical guide plate was created according to the working channel,and the osseous structure of the guide plate to the inner edge channel of the vertebral arch root was observed,and the range of facet joint defect(j)was measured.(2)All the 13 patients underwent thoracic discectomy via percutaneous endoscopic posterolateral approach.Visual analogue scale score,Japanese Orthopedic Association thoracic spinal function score,Oswestry disability index and modified MacNab were used to evaluate the clinical efficacy.The study was approved by the Ethics Committee of Binzhou Medical Unive rsity Hospital.RESULTS AND CONCLUSION:(1)There was no significant difference in the distance from Y point of T2/3-T10/11 vertebral body to the lateral edge of the dura mater(P>0.05),There was no significant difference in the distance from Y point of the T1/2-T10/11 vertebral body to the medial edge of the facet joint(P>0.05),(2)Y point on the sagittal plane of the T1/2 vertebral body was projected above the inte rvertebral space,while Y point on the sagittal plane of the other segments was projected at the level of intervertebral space.(3)T1/2vertebral body h<i,guide plate abduction without scapula barrier;T2/3-T4/5 vertebral body h>i,the guide plate was blocked by the scapula during abduction.(4)Vis u al analogue scale,Japanese Orthopedic Association thora cospinal function scale and Oswestry disability index score of the 13 patients in the last follow-up were significantly im p roved compared with those before surgery(P<0.05);the excellent and good rate after modified MacNab was 92%.(5)The posterior lateral approach of percutaneous endosco py was applicable to paracentral soft thoracic disc herniation due to the deep location of T1/2-T4/5 segments,which were blocked by the shoulder blades and the work passage was limited in extension.In T5/6-T11/12segments,this technique is applicable to various types and pro perties of thoracic disc herniation(except for giant type).(6)Results confirm that Y point can be used as a marker of bone localization under endoscope,and its constant projection on the sagittal surface is at the level of inte rvertebral space(except T1/2).The diffe rent bone structure of each thora cic ve rtebra segment should be removed to establish the bone channel.The treatment of thoracic disc herniation by percutaneous endoscopic posterolateral approach is effective,safe and feasible.