双椎弓根螺钉固定技术治疗腰椎融合术后相邻节段病变

Dual pedicle screws technique for revision surgery of adjacent segment degeneration after lumbar fusion surgery

中文关键词:  腰椎融合  相邻节段病变  椎弓根螺钉  皮质骨通道

英文关键词:Lumbar spine fusion  Adjacent segmental disease  Pedicle screw  Cortical bone trajectory

中文摘要:

  【摘要】 目的：观察双椎弓根螺钉固定技术治疗腰椎融合术后相邻节段病变的可行性和临床疗效。方法：回顾性分析我科2016年8月~2018年10月手术治疗腰椎融合术后的相邻节段病变（adjacent segment disease，ASD）患者36例，按照手术方式分为两组，A组（双钉组）：12例，男女比例（4∶8），年龄66.2±4.2岁（59~74岁），首次术后2~7年，均为头侧椎节病变。使用双椎弓根螺钉（dual screws，DS）固定技术，于原手术侧椎弓根再次各置入一枚翻修螺钉，ASD另一端置入皮质骨通道螺钉，减压后短节段融合固定。B组（对照组）：24例，男女比例（9∶15），年龄64.0±7.7岁（46~72岁），平均首次术后2~10年，19例为头侧椎节退变，5例为尾侧椎节病变。手术取下双侧固定棒，采用Magerl方法置入ASD远端椎弓根螺钉、减压责任节段后延长棒固定。记录每例患者手术时间、术中出血量、术后并发症，腰椎ODI评分、腰痛VAS、腿痛VAS。通过腰椎X线片、CT评价术后患者的内固定位置和椎间融合状态。比较两组间和组内的临床评分差异性。结果：术后平均随访16.1±5.8个月（6~26个月）。ODI评分A组术前（82.5±16.7）%，末次随访（16.0±8.9）%；B组术前（78.0±14.6）%，末次随访（18.0±9.4）%；腰痛VAS，A组术前8.3±3.5分，末次随访1.7±0.9分；B组术前6.7±4.5分，末次随访2.1±1.3分；腿痛VAS，A组术前6.3±4.5分，末次随访1.0±1.0分；B组术前7.8±3.4分，末次随访2.3±2.4分。两组末次随访的ODI和VAS均较术前有明显改善（P<0.05）。两组间的术前ODI、腰痛VAS、腿痛VAS无明显差异（P>0.05）；两组间的术前、末次随访ODI、VAS、手术时间均无明显差异（P>0.05）。B组的手术出血量、住院时间明显大于A组（P<0.05）。A组无手术切口感染、无神经症状加重病例，1例术中硬脊膜撕裂，予以修复。B组术中硬脊膜撕裂5例，术中修复或者皮下脂肪覆盖，伤口表浅感染1例，经过换药治愈。A组共置入24枚双钉技术的翻修螺钉（L1椎体2枚，L2椎体12枚，L3椎体10枚），其中18位置良好，4枚螺钉穿破椎体外侧壁，2枚螺钉穿破椎弓根内侧壁，但无神经症损伤症状，随访无内固定松动。B组再次植入48枚椎弓根螺钉，螺钉位置良好，无穿破椎体和椎弓根病例。末次随访的A组椎间融合8例，B组18例。翻修螺钉平均螺钉头倾角6.7°±6.6°（3°~16°），平均外展角度10.3°±7.4°（0°~15°）。B组无螺钉相关合并症。结论：个体化双椎弓根螺钉固定技术为腰椎融合术后相邻节段病变提供一种新的微创解决方案，短期临床预后良好。

英文摘要:

  【Abstract】 Objectives: To investigate the feasibility and clinical efficacy of dual pedicle screws technique in revision for adjacent segment degeneration after lumbar fusion. Methods: From August 2016 to October 2018, 36 patients with adjacent segment disease(ASD) after previous thoracolumbar fusion were surgically treated in our department. The patients were divided into two groups according to the surgical procedures. Group A (Dual screws group): 12 patients (4 males and 8 females) with an average age of 66.2±4.2 years old (59-74); at 2 to 7 years after the first operation, with all ASD levels located in cephalic segments. First, the ASD segment was exposed, using Dual Screws(DS) technique, pedicle screw was implanted into the pedicle where there was already a pedicle screw, and the cephalad side of the ASD segment was inserted with cortical bone trajectory(CBT) screws. After decompression, short segmental fusion was performed. Group B(Control group): 24 patients (9 males and 15 females) with an average age of 64.0±7.7 years old (46-72); at 2 to 10 years after the first operation, with 19 ASD located in cephalic segments and 5 located in caudal segments. During the surgery, the previous surgical area was exposed and bilateral fixation rods were removed. The distal vertebral pedicles of ASD segment were inserted with screws using Magerl technique. Bilateral elongated rods were fixed after decompression of the responsible segment. The operation time, blood loss and postoperative complications were recorded. Pre- and postoperative ODI scores, low back pain VAS and leg pain VAS were also recorded. The position of internal fixation and intervertebral fusion were evaluated by X-ray and CT. The differences of clinical scores between and within each group were compared. Results: The ODI scores at pre-operation and final follow-up of group A were (82.5±16.7)% and (16.0±8.9)%, and that of group B were (78.0±14.6)% and (18.0±9.4)% respectively. The VAS back pain scores atpre-operation and final follow-up of group A were 8.3±3.5 and 1.7±0.9, and group B were 6.7±4.5 and 2.1±1.3 accordingly. The VAS leg pain at pre-operation and final follow-up of group A were 6.3±4.5 and 1.0±1.0, and group B were 7.8±3.4 and 2.3±2.4 accordingly. All patients were followed up for a average of 16.1±5.8 months(6-26 months). The ODI and VAS scores of the two groups were significantly improved after the revision(P<0.05). There was no significant difference in preoperative ODI score, VAS back pain score and VAS leg pain score between the two groups (P>0.05). There was no significant difference in preoperative and postoperative clinical scores and operation time between the two groups(P>0.05). The amount of intraoperative blood loss and the length of in-hospital time in group B were significantly greater than that in group A(P<0.05). There were no cases of surgical site infection and aggravated neurological symptoms in group A, while 1 case of intraoperative dural tear was repaired in group A. In group B, 5 cases of dural tear were repaired during operation or covered with subcutaneous fat, and 1 case of superficial wound infection was cured by dressing change. A total of 24 revision pedicle screws using dual pedicle screws technique were inserted, 18 of them were in good position, 4 screws penetrated the outer wall and 2 penetrated the inner wall of pedicles. However, there were no neurological injuries, no internal fixations loosing. In group B, 48 pedicle screws were inserted with no penetration and were all in good positions; at the final follow up, 8 cases of bony intervertebral fusion could be seen on CT scan in group A and 18 cases in group B. The average inclination angle of revision screws is 6.7°±6.6°(3°-16°). The average abduction angle was 10.3°±7.4°(0°-15°). Group B had no screw-related complications. Conclusions: The individualized dual pedicle screw fixation technique proposed a new minimally invasive alternative for surgical revision ASD after lumbar fusion. The clinical results of short-term follow-up were fairly good.