俯卧位加压CT定位像在无神经症状胸腰段骨折畸形愈合继发后凸畸形矫形术中的意义

Clinical significance of prone full-spine compression CT image in correction of kyphosis secondary to malunion of thoracolumbar fractures without neurological symptoms

目的探讨俯卧位加压CT定位像在无神经症状胸腰段骨折畸形愈合继发后凸畸形矫形术中的意义。方法回顾2016年12月~2018年7月本院收治的14例无神经症状脊柱骨折伴后凸畸形患者临床资料,男1例,女13例;年龄47~73岁,平均(65.6±7.2)岁。统计分析患者术前站立位、俯卧位加压CT定位像、术后及末次随访时局部后凸Cobb角(local kyphotic cobb angle,LKCA)、胸腰段后凸Cobb角(thoracolumbar kyphosis,TLK)、VAS评分、ODI指数及截骨级别等数据。计算脊柱后凸柔韧性(spinal flexibility,SF)、矫正率。对术前站立位X线、俯卧位加压CT定位像局部Cobb角、SF与截骨级别的关系进行相关性分析;回归分析验证俯卧位加压CT定位像预测手术矫形效果能力。结果所有患者均行矫形手术并获随访,其中未截骨2例,I级截骨1例,II级截骨4例,Ⅲ级截骨3例,IV级截骨4例;随访时间23-42个月,平均(26.14±5.8)个月。术前、术后2周及末次随访VAS评分分别为(7.2±1.3)、(4.1±2.4)、(1.3±0.4)分,ODI指数为分别为(51.6±4.93)%、(30.2±2.76)%、(10.08±1.77)%,术后及末次随访较术前明显改善(P<0.05)。术后及末次随访时LKCA、TLK较术前明显改善,末次随访时矫正率49%~91%,平均(78.1±10.1)%,SF值为6.9%~60.61%。术前站立位LKCA及俯卧位加压CT定位像LKCA与截骨级别相关系数分别为0.73、0.88,SF与截骨级别、畸形矫正率无关。回归分析显示:俯卧位加压CT定位像LKCA、TLK与末次随访时LKCA、TLK呈线性关系,线性方程分别为:LKCA末次随访=0.22×LKCACT定位+2.3(r=0.64;P<0.05);TLK末次随访=0.2268×TLKCT定位+1.8696(r=0.735;P<0.05)。结论俯卧位加压CT定位像测量的LKCA与截骨级别的选择显著相关,可指导手术方案的制定;SF不能预测矫正率,但俯卧位加压CT定位像可预测术后LKCA及胸腰段后凸Cobb角。

Objective To investigate the clinical significance of prone full-spine compression CT image in correction of kyphosis secondary to malunion of thoracolumbar fractures without neurological symptoms.Methods The clinical data of 14 patients with kyphosis secondary to malunion of thoracolumbar fractures without neurological symptoms admitted to our hospital from December 2016 to July 2018 were retrospectively analyzed. There were 1 male and 13 females, aged from 47 to 73 years old, with an average of(65. 6±7.2) years old. The preoperative standing, prone compressed CT image, the local kyphosis Cobb angle(LKCA), thoracolumbar kyphosis Cobb angle(TLK), correction rate, VAS score and ODI score at 2 weeks after operation and last follow-up were statistically analyzed.The spinal flexibility(SF) and deformity correction rate were calculated. The relationship between preoperative standing X-ray, prone CT positioning image and osteotomy level was analyzed. The ability of prone CT positioning image to predict orthopedic effect was also judged.Results All patients underwent orthopedic surgery and were followed up, including 2 cases without osteotomy, 1 case with grade I osteotomy, 4 cases with grade II, 3 cases with grade Ⅲ and 4 cases with grade IV. The follow-up time ranged from 23 to 42 months,average(26. 14 ± 5. 8) months. Before operation, at two weeks after operation and the last follow-up, the VAS scores were(7. 2±1. 3),(4. 1±2. 4) and(1. 3±0. 4), respectively;the ODI index were(51. 6% ±4. 93%),(30. 2% ±2. 76%),(10. 08% ±1. 77%), thoseat two weeks after operation and the last follow-up were significantly improved compared with before operation(P<0. 05). The LK andTLK at two weeks after operation and the last follow-up were significantly improved compared with before operation. At the last followup, the correction rate was 49% ~ 91%, average(78. 1±10. 1)%, SF ranged from 6. 9% to 60. 61%. The correlation coefficientsbetween LK in standing and prone image with osteotomy grade were 0. 73 and 0. 88, respectively. The flexibility of kyphosis was notrelated to osteotomy grade and deformity correction rate. Regression analysis showed a linear relationship between LK and TLK atpreoperation and last follow-up, with equation: LKCAlast follow-up= 0. 22×LKCAprone CT+ 2. 3(r= 0. 64,P<0. 05), TLKlast follow-up= 0.2268×TLKprone CT+ 1. 8696(r= 0. 735,P< 0. 05).Conclusion The Cobb angle of local kyphosis measured by prone full-spinecompression CT image is significantly correlated with the choice of osteotomy level, with ability of directing operation plan. The flexibilityof kyphosis cannot predict the correction rate, but prone full-spine compression CT image can predict the Cobb angle of local kyphosisand the Cobb angle of thoracic kyphosis after operation.