肌间隙入路通道下固定融合治疗复发性腰椎间盘突出症

目的:探讨肌间隙入路通道下单侧椎弓根螺钉联合对侧椎板关节突螺钉固定并椎间融合器植骨治疗复发性腰椎间盘突出症的临床价值和安全性。方法:回顾性分析2012年6月至2017年12月收治的51例复发性腰椎间盘突出症的临床资料。男32例,女19例;年龄34~64(51.11±7.28)岁;L4,538例,L5S113例;均有腰痛病史,其中3例伴双下肢放射痛,48例伴一侧下肢放射痛。24例患者采用正中切口入路单侧椎弓根螺钉联合对侧椎板关节突螺钉固定并椎间融合器植骨治疗(正中切口组),27例采用肌间隙入路通道下单侧椎弓根螺钉联合对侧椎板关节突螺钉固定并椎间融合器植骨治疗(肌间隙组)。记录两组患者手术时间、术中出血量、术后引流量和切口长度;采用视觉模拟评分法(visual analogue scale,VAS)对术后72 h腰部切口疼痛进行评分,采用JOA下腰痛评分系统评定术前及末次随访时两组患者腰椎功能;通过影像学资料观察术前、术后3~5 d和末次随访时病变节段椎间隙高度的变化,术前和末次随访时腰椎冠状面和矢状面Cobb角变化,术前和术后12个月多裂肌面积和多裂肌脂肪组织沉积等级,术后椎弓根螺钉和椎板关节突螺钉位置,以及椎间融合情况;比较两组患者并发症发生情况。结果:两组患者手术时间比较差异无统计学意义(P>0.05)。肌间隙组在切口长度、术中出血量和术后引流量方面优于正中切口组(P<0.05)。术后72 h腰部切口疼痛VAS评分正中切口组1.61±0.54,肌间隙组0.76±0.28,两组比较差异有统计学意义(P<0.05)。所有患者获得随访,时间12~84(43.50±15.84)个月。末次随访时两组JOA评分均较术前明显改善(P<0.05)。椎弓根螺钉位置不良率:正中切口组6.25%(3/48),肌间隙组9.26%(5/54),两组差异无统计学意义(P>0.05)。椎板关节突螺钉位置不良率:正中切口组12.50%(3/24),肌间隙组18.52%(5/27),两组差异有统计学意义(P<0.05)。两组患者术后3~5 d椎间隙高度较术前均有明显恢复(P<0.05),而在末次随访时亦有较明显的丢失(P<0.05)。末次随访时两组患者冠状面和矢状面平衡获得了很好的改善(P<0.05)。两组术后12个月多裂肌面积和等级的对比显示:正中切口显露对多裂肌损害明显,而采用肌间隙入路通道下操作多裂肌损害较轻(P<0.05)。椎间融合率:正中切口组91.7%(22/24),肌间隙组92.6%(25/27),两组差异无统计学意义(P>0.05)。并发症方面:正中切口组术中椎弓根入点骨折1例,术中硬脊膜撕裂1例,术后神经根损伤1例;肌间隙组术中椎弓根入点骨折1例,术中硬脊膜撕裂2例,术后神经根损伤1例,切口表皮坏死2例,切口愈合不良1例。两组神经根损伤均为椎弓根螺钉位置不正确所致,发现后即予螺钉调整术,神经根症状分别于术后3、6个月完全恢复。两组均未发生切口感染,随访过程中无椎弓根螺钉与椎板关节突螺钉松动、移位、断裂或椎间融合器前后向移位。并发症发生率肌间隙组25.93%高于正中切口组的12.50%(P<0.05)。结论:采用肌间隙入路通道下单侧椎弓根螺钉联合对侧椎板关节突螺钉固定并椎间融合治疗复发性腰椎间盘突出症临床上具有可行性,而且效果良好,与正中切口显露相比,明显缩小了切口、减少了创伤和出血量,术后反应轻、恢复快,较好地保护了多裂肌,同时无严重并发症的发生,值得临床上选择应用。

Channel-assisted fixation and interbody fusion in treating recurrent lumbar disc herniation by muscle-splitting approach

Objective: To explore the clinical value and safety of unilateral pedicle screw fixation combined with contralateral translaminar facet screw fixation and interbody fusion by muscle-splitting approach treatment of recurrent lumbar disc herniation. Methods: The clinical data of 51 patients with recurrent lumbar disc herniation treated from June 2012 to December 2017 were retrospectively analyzed. There were 32 males and 19 females,aged 34 to 64 years with an average of(51.11±7.28) years. Lesions invoved L_4,5 in 38 cases and L₅S₁ in 13 cases. All patients had a history of lower back pain and radiation pain of lower limbs(3 bilateral and 48 unilateral) and underwent unilateral pedicle screw combined with contralateral translaminar facet screw fixation and interbody fusion,among which 24 patients were treated through median incision approach (median incision group);other 27 patients were treated through muscle-splitting approach with channel-assisted exposure(muscle-splitting approach group). Operation time,intraoperative blood loss,postoperative drainage and incision length of the two groups were recorded. Visual analogue scale(VAS) was used to score the pain of lumbar incision at 72 h after operation,and JOA low back pain scoring system was used to evaluate the lumbar function preoperatively and at final follow-up. Imaging data were analyzed,including the changes in the height of intervertebral space of diseased segment before operation,3 to 5 days after operation,and at final follow-up;Cobb angle changes in the coronal and sagittal planes of lumbar spine preoperatively and at final follow-up;multifidus area and multifidus fatty tissue deposition grade before and 12 months after operation; postoperative pedicle screw and laminar process screw position and intervertebral fusion condition. The complications of the two groups were compared. Results: There was no statistical difference in operation time between two groups(P>0.05). Muscle-splitting approach group was better than median incision group in light of incision length,intraoperative blood loss and postoperative drainage volume(P<0.05). VAS score of lumbar incision pain at 72 h after operation was 1.61±0.54 in median incision group and 0.76±0.28 in muscle-splitting approach group(P<0.05). All patients were followed up for 12 to 84 (43.50±15.84) months. At final follow-up,the JOA scores of the two groups were significantly improved compared with those before operation(P<0.05). The rate of pedicle screw malposition was 6.25%(3/48) in median incision group and 9.26%(5/54) in muscle-splitting approach group,there was no statistically significant difference between two groups(P>0.05). Rate of translaminar facet screw malposition in median incision group (12.50%) was significant less than the muscle-splitting approach group (18.52%)(P<0.05). The height of the intervertebral space of the two groups was significantly restored 3 to 5 days after operation(P<0.05),and there was also a significant loss of height at final follow-up (P<0.05). At final follow-up,the balance of lumbar coronal plane and sagittal plane in two groups were improved very well(P<0.05). The comparison of the area and grade of the multifidus muscle in two groups 12 months after operation showed that obvious damage to the multifidus muscle were present in the median incision,while the multifidus muscle was less damaged by muscle-splitting approach(P<0.05). The fusion rate was 91.7%(22/24) in the median incision group and 92.6%(25/27) in muscle-splitting approach group(P>0.05). In median incision group,there were 1 case of intraoperative pedicle entry point fracture,1 case of intraoperative dural tear and 1 case of postoperative nerve root injury;in muscle-splitting approach group,there were 1 case of intraoperative pedicle entry point fracture,2 cases of intraoperative dural tear,1 case of postoperative nerve root injury,2 cases of incision epidermal necrosis and 1 case of poor incision healing. Nerve root injuries in the two groups were caused by incorrect positions of pedicle screws,the screws were immediately adjusted upon discovery. The nerve root symptoms were completely recovered 3 and 6 months after surgery. No incision infection was occurred in two groups. During the follow-up,no pedicle screw and laminar facet screw were loosened,displaced,broken,or intervertebral fusion cage moved forward and backward. The complication rate of 25.93% in muscle-splitting approach group was higher than 12.50% in the median incision group (P<0.05). Conclusion: Muscle-splitting approach is feasible for the treatment of recurrent lumbar disc herniation with pedicle screw fixation combined with contralateral translaminar facet screw fixation and interbody fusion. Compared with the median incision approach,the muscle-splitting approach has the advantages of small incision,less trauma,less bleeding,rapid recovery. Also it can protect multifidus and do not increase the incidence of serious complications. Thus,it can be used as a choice for fixation and fusion of recurrent lumbar disc herniation.