经皮内镜椎间孔入路椎间盘切除术中常规行椎间孔成形的必要性

Necessity of routinely performing foraminoplasty during percutaneous endoscopic transforaminal discectomy in treating lumbar disc herniation

目的探讨经皮内镜椎间孔入路椎间盘切除术(percutaneous endoscopic transforaminal discectomy,PETD)中常规行椎间孔成形的必要性。方法 2011年1月至2018年1月因单节段腰椎间盘突出症行PETD手术的患者412例,男231例,女181例;年龄(39.1±13)岁(范围20~80岁)。病变节段:L3-4 32例,L4-5 289例,L5S1 91例。无脱垂306例,轻度向上或向下脱垂89例,重度脱垂17例。采用MRI 矢状面T1WI或T2WI影像测量L3,4、L4,5及L5S1椎间孔高度、宽度、出口根与下位椎弓根上缘的距离、椎间隙后缘腹侧3 mm处与上关节突的距离。采用动力位X线片测量椎间孔宽度变化评估椎间孔成形的必要性,并于术中验证。结果 L3~S1椎间孔高度分别为(1.99±0.25)、(1.89±0.15)、(1.52±0.26) cm;宽度分别为(0.78±0.14)、(0.75±0.13)、(0.64+0.13) cm;出口根与下位椎弓根上缘的距离分别为(1.14±0.17)、(1.05±0.16)、(0.98±0.19) cm;椎间隙后缘腹侧3 mm处与上关节突的距离分别为(1.11±0.31)、(1.17±0.20)、(0.95±0.14) cm。过屈位X线片测量L3,4及L4,5节段椎间孔宽度均明显大于过伸位(P<0.05)。术中证实需行椎间孔成形者65例(15.8%,65/412),其中L4,5节段31例(10.7%,31/289)、L5S1节段34例(37.4%,34/91),L3,4节段无需椎间孔成形。未行椎间孔成形组(347例)及椎间孔成形组(65例)各1例因椎间盘残留行二次手术。术后2年随访时,未行椎间孔成形组4例复发、椎间孔成形组2例复发。未行椎间孔成形组腰痛Oswestry功能障碍指数及日本整形外科学会评分[18%±9%、(24.2±1.3)分]与椎间孔成形组[16%±7%,(23.9±1.3)分]的差异无统计学意义(t=1.70,P=0.090;t=1.71,P=0.088);两组腰痛视觉模拟评分分别为(0.9±0.4)、(1.9±0.6)分,差异有统计学意义(t=16.92,P<0.001)。结论腰椎PETD术中,多数L3~L5节段不需要椎间孔成形,L5S1节段需行椎间孔成形的比例较高。在采用half-half技术结合远外侧穿刺的基础上无需常规行椎间孔成形,应根据术前椎间孔测量及术中观察综合判断其必要性。

Objective To analyze the necessity of routinely performing foraminoplasty during percutaneous transforaminal endoscopic discectomy (PETD). Methods A total of 412 patients including 231 males and 181 females with an average age of 39.1±13 (20-80) years were enrolled in the present study. All patients were preoperatively diagnosed with single-segment lumbar disc herniation and underwent PETD by the same surgical group. The affected segments were at L3-4 in 32 cases, L4-5 in 289 cases, and L5S1 in 91 cases. Among them, 306 cases had no prolapse, 89 had mild up/down prolapse, and 17 had severe prolapse. MRI sagittal imaging was used to measure the height and width of the intervertebral foramen of L3, 4, L4, 5 and L5S1 segments, the distance between the lower edge of vertebral pedicle and the upper edge of the lower vertebral pedicle and the distance between the point 3 mm to the ventral side of the intervertebral space to the superior articular process. The necessity of performing foraminoplasty was evaluated by measuring the change of intervertebral foramen width using dynamic X-ray and verified during operation. Results The height of the intervertebral foramen of L3, 4, L4, 5 and L5S1 segments were 1.99±0.25, 1.89±0.15 and 1.52± 0.26 cm, respectively. The width of the intervertebral foramen was 0.78±0.14, 0.75±0.13 and 0.64±0.13 cm, respectively. The distance between the lower edge of vertebral pedicle and the upper edge of the lower vertebral pedicle were 1.14±0.17, 1.05±0.16, and 0.98±0.19 cm, respectively. The distance between the point 3 mm to the ventral side of the intervertebral space to the superior articular process were 1.11±0.31, 1.17±0.20, and 0.95±0.14 cm, respectively. The width of the intervertebral foramen of the L3, 4 and L4, 5 segments was significantly greater at the over-flexion position than at the over-extension position (P<0.05). Intraoperative verification showed that 347 cases (group A) did not need foraminoplasty. However, the other 65 patients (group B) needed foraminoplasty, including 31 at L4, 5 segment and 34 at L5S1 segment. One patient in group A and one in group B underwent revision operation due to residual intervertebral disc. At 2 years of follow-up, recurrence occurred in 4 patients in group A and 2 patients in group B. The ODI score and JOA score in group A and B were 18%±9%, 24.2±1.3 and 16%±7%, 23.9±1.3, respectively. There were not significantly different between patients in group A and B (t=1.70, P=0.090;t=1.71, P=0.088). The VAS score of lumbar pain of patients in group A was better than that of patients in group B (P<0.05). Conclusion Most of PETD of L3-S1 segments can reach the therapeutic target without performing foraminoplasty with half-half technique combined with far lateral access technique. Due to the special anatomical position of L5-S1 segment, the probability of performing foraminoplasty during operation is much higher. Performing foraminoplasty or not depends on the preoperative measurement of foramina and verification during the operation.