强直性脊柱炎颈胸段后凸畸形截骨术后并发症及其治疗策略

Complications following cervicothoracic osteotomy for cervico-thoracic kyphosis caused by ankylosing spondylitis and treatment

中文关键词:  强直性脊柱炎  颈胸段后凸畸形  经椎弓根椎体截骨术  并发症  神经根麻痹

英文关键词:Ankylosing spondylitis  Cervico-thoracic kyphosis  Pedicle subtraction osteotomy  Complication  Radiculopathy

中文摘要:

  【摘要】 目的：探讨强直性脊柱炎（ankylosing spondylitis，AS）颈胸段后凸畸形患者截骨术后并发症的发生率、临床表现及治疗策略。方法：回顾性分析我院脊柱外科自2006年1月~2018年12月接受颈胸段截骨矫形治疗的11例AS患者，年龄14~60（33.4±14.0）岁。其中3例患者因前纵韧带骨化程度较轻行C7~T1伸展性截骨矫形，8例患者因前纵韧带骨化严重行C7经椎弓根椎体截骨（pedicle subtraction osteotomy，PSO）矫形。在X线片上测量参数包括术前、术后1周及末次随访时颈胸段后凸角、颈胸段矢状面偏移（C2-T1 sagittal vertical axis，C2 SVA）、颌眉角（chin-brow vertical angle，CBVA）、冠状面Cobb角和冠状面平衡距离（coronal balance distance，CBD）。同时记录术后相关并发症的发生情况、临床表现及治疗转归。结果：11例患者均获得随访，平均随访时间为16.45（6~48）个月。术后1周颈胸段后凸角、C2 SVA与CBVA较术前明显改善（-11.45°±13.98° vs 17.64°±14.03°、48.64±23.56mm vs 84.27±36.90mm、10.18°±9.47° vs 42.45°±22.46°，均P<0.05）；末次随访时较术后1周无明显矫正丢失（P>0.05）。3例患者合并侧凸畸形，术前CBD和冠状面Cobb角分别为48.5mm、37.0mm、78.7mm和47.3°、26.8°、20.5°，术后1周改善至14.1mm、6.1mm、24.8mm和14.4°、9.3°、6.3°。末次随访时所有参数未见明显矫正丢失，骨性融合良好。所有患者随访期间未出现感染、螺钉松动、断钉断棒等内固定相关并发症。3例C7 PSO患者出现术后并发症，发生率为27.3%（3/11）。其中1例为截骨椎脱位，表现为单侧上肢的麻木乏力，另2例出现C8神经根麻痹症状，1例表现为右手远端指节屈曲障碍，另1例出现左前臂尺侧麻木及左上肢伸肘肌力下降。3例患者均采用颈胸外固定支具及掌指功能锻炼后于末次随访时完全恢复正常，症状改善时间为术后6个月。结论：C8神经根麻痹或截骨椎脱位为AS颈胸段后凸畸形截骨术后常见并发症。对于前者，若术中减压充分、电生理无异常、术后即刻CT显示无脱位，可暂不探查，予保守治疗（卧床+支具）至骨性愈合；反之，若出现肌力下降且CT提示脱位，则需探查。对于后者，若脱位椎体未对神经造成明显压迫，且未合并神经功能损害，可采用支具保守治疗；若脱位已引发神经症状，或存在较大范围骨质缺损，则应考虑外科手术干预。

英文摘要:

  【Abstract】 Objectives: The study aimed to investigate the incidence, clinical manifestations and prognosis of complications following cervico-thoracic osteotomy for cervico-thoracic kyphosis(CTK) secondary to ankylosing spondylitis(AS). Methods: A retrospective study of 11 AS patients with CTK who underwent surgery were performed. The average age was 33.4±14.0 years(range, 14-60 years). C7-T1 extensive osteotomy was performed in 3 cases with mild ossified anterior longitudinal ligament(OALL) while C7 pedicle subtraction osteotomy(PSO) was performed in 8 patients with severe OALL. Radiographs were analyzed for C2-T1 kyphosis(CK), C2-T1 sagittal vertical axis(C2 SVA), chin-brow vertical angle(CBVA), C2-7 Cobb angle in coronal plane and coronal balance distance(CBD) preoperatively, 1 week postoperatively and at final follow-up. Postoperative complications were also recorded including incidence, clinical manifestation and prognosis. Results: The mean follow-up period was 16.45 months(range, 6-48 months). The CK, C2 SVA and CBVA significantly improved at postoperative 1 week compared with those before operation(-11.45°±13.98° vs 17.64°±14.03°, 48.64±23.56mm vs 84.27±36.90mm, 10.18°±9.47° vs 42.45°±22.46°, all P<0.05), which showed no significant loss at final follow-up(P>0.05). Three patients presented with concomitant coronal deformity. The preoperative CBD and coronal Cobb angles were 48.5mm, 37mm, 78.7mm and 47.3°, 26.8°, 20.5° respectively, which were improved to 14.1mm, 6.1mm, 24.8mm and 14.4°, 9.3°, 6.3° one week after surgery. No obvious loss of correction was observed for all the parameters at final follow-up. The incidence of complications was 27.3% (3/11), including one case of osteotomized vertebral subluxation(VS) and two cases of C8 radiculopathy. The patient with VS presented with weakness and numbness of unilateral upper extremity. For the two patients with C8 radiculopathy, one presented with weakness of intrinsic muscles in the right hand, the other had numbness and weakness of left arm. The symptoms of the three patients were relieved six months postoperatively after rehabilitation and Halo-vest immobilization. Conclusions: C8 radiculopathy and VS were common complications following cervicothoracic osteotomy in AS patients with CTK. For patients with C8 radiculopathy, conservative treatment(rest and brace) till bony fusion could be considered first when there is extensive laminectomy intra-operatively, without abnormal intraoperative neuro-monitoring signals or VS on sagittal CT reconstruction, otherwise, surgical exploration should be performed when there is progressive muscle strength decrease and VS on CT image. For the VS, conservative bracing was indicated in the absence of significant neural compression or neurological deficits secondary to vertebral dislocation; Conversely, surgical intervention was warranted if dislocation resulted in neurological symptoms or was accompanied by extensive osseous defects.