可动式椎间盘镜下MED-LIF手术的设计与临床应用

The design and clinical application of MED-LIF with mobile microendoscopic discectomy technique

目的为腰椎椎间盘退变性疾患提供一种可达到充分减压和腰椎椎体间融合（LIF）的微创手术方法。方法可动式椎间盘镜（MMED）由外层操作套管和内层手术套管构成，根据LIF的操作需要，研制可通过12、14mm高度融合器的大号操作套管。设计手术方法：在症状严重侧的椎弓根投影连线与棘突之间行纵行切口，紧贴棘突安置操作套管，MMED下经椎板间隙开窗减压，切除椎间盘，刮除椎间盘和终板软骨，如对侧狭窄可经硬膜囊背侧行对侧潜行减压；退出手术套管，松解椎间隙并植骨、植入融合器，透视下经皮椎弓根螺钉复位固定。临床应用MMED行椎间盘镜下腰椎椎体间融合（MED-LIF）手术治疗腰椎间盘退变性疾病患者102例，节段包括L3411例、L4564例、L5S121例、L3~53例、L4~S13例。记录手术时间、出血量，随访评估疗效。结果患者均未发生神经损伤等严重并发症，1例因螺钉位置不佳中转开放手术。手术时间90~200min，平均（120±30）min，术中出血50~300mL，平均（120±80）mL。术后X线片和CT示内固定位置良好，减压充分并保留对侧骨性结构。术后随访6~36个月，功能障碍指数（ODI）由术前44.2%±16.3%降至末次随访的4.9%±4.7%；疼痛视觉模拟评分（VAS）腰痛由术前（5.3±4.1）分降至（2.1±1.7）分，腿痛由术前（6.7±3.5）分降至（1.0±0.8）分。根据Macnab标准：优46例、良50例、可6例。结论MMED下MED-LIF治疗腰椎间盘退变性疾病可达到充分减压、复位及融合固定，同时减少手术创伤和稳定结构的破坏。

Objective To evaluate the feasibility and clinical efficacy of microendoscopic discectomy- lumbar interbody fusion (MED-LIF) with mobile microendoscopic discectomy (MMED) technique. Methods The MMED includes outer working canal and inner operating canal, and large working canals (12 mm and 14 mm) are fabricated for this operation.The operation was designed as follow: an incision was made between pedicle projection sites and spinous process on the side with prominent symptom. Working canal was inserted along spinous process and a fenestration was performed. After discectomy and ipsilateral decompression, contralateral nerve was decompressed in case of contralateral stenosis. Then the intervertebral space was prepared and grafted. The inner operating canal was removed and the suitable cage was inserted,followed by percutaneous pedicles screws installation, reduction and fixation. A total of 102 patients with lumbar degenerative disc disease were treated by this technique. The index levels included L34 (n=11), L45 (n=64), L5S1 (n=21),L3-5 (n=3), and L4-S1(n=3). The operative data and follow-up results were recorded and evaluated. Results Surgery was successful in all patients, with no nerve injury or conversion to open surgery. The mean operative time was (120±30) min (range, 90-200 min), with a mean blood loss of (120±80) mL (range, 50-300 mL). The post-operative X-ray and CT scans showed improvement of spinal alignment with sufficient decompression. Patients were followed up for 6 to 36 months. The Oswestry disability index (ODI) score decreased from the pre-operative 44.2%±16.3% to the last follow-up 4.9%±4.7%. The visual analog pain score (VAS) of lumbar decreased from the pre-operative 5.3±4.1 to the last follow-up 2.1±1.7, and VAS of leg decreased from the pre-operative 6.7±3.5 to 1.0±0.8 at final follow-up. The clinical results were excellent in 46 cases,good in 50 cases and fair in 6 cases according to the Macnab standard. Conclusion MED-LIF can be easily performed with MMED technique, with sufficient decompression and reduction, providing satisfactory results with less invasive procedure.