先天性脊柱侧凸双节段平衡型半椎体畸形的影像学分析

Imaging analysis of balanced double hemivertebrae in congenital scoliosis

目的 分析双节段平衡型半椎体患者脊柱畸形的影像学特点。方法 对2016年1月至2020年6月,于我院就诊的28例双节段平衡型半椎体所致的先天性脊柱侧凸患者的影像学资料进行回顾性分析。患者平均年龄3.4岁,男16例,女12例。通过全脊柱X线测量患者节段性侧凸角、胸椎(T5~12)后凸角、胸腰段(T10~L2)后凸角、骶骨倾斜角、骨盆倾斜角、腰椎前凸、头端及尾端代偿弯、冠/矢状面平衡等参数。通过CT及MRI判断前方半椎体和后方附件的畸形情况、患者是否合并肋骨畸形及椎管内异常。按半椎体分布位置将畸形分为4型:1型:胸椎+胸椎;2型:腰骶椎+腰椎;3型:胸椎+腰骶椎;4型:胸椎+颈椎,对比分析不同畸形患者的各项影像学指标。结果 患者各节段半椎体数量:C_(1~7):2,T_(1~5):8,T_(6~12):18,L_(1)~S_(1:28),半椎体主要分布于腰骶段(50.0%)和下胸椎(32.1%),以半分节型(51.8%)为主,胸腰段半椎体多达24个(42.9%)。两半椎体平均间隔3.5个正常椎体,前方椎体和后方附件以协调型最为常见(82.1%)。畸形分型:1型患者7例,2型9例,3型10例,4型2例。患者头端和尾端节段性侧凸角分别为(34.7±7.5)°和(34.7±9.6)°,两者差异无统计学意义(t=0.005,P=0.996)。不同畸形类型患者的节段性侧凸角、头端代偿弯、冠/矢状面平衡、骶骨倾斜角、骨盆倾斜角、胸椎后凸角差异均无统计学意义(P> 0.05)。2型患者尾端代偿弯、腰椎前凸及胸腰段后凸角明显偏小。5例合并邻近椎体畸形、肋骨畸形、中央管扩张或椎板裂。结论 双节段平衡型半椎体畸形较为复杂,半椎体主要分布于腰骶段和下胸椎,与冠状面相比畸形对患者矢状面的影响更为明显。

Objective To analyze the imaging characteristics of balanced double hemivertebrae in congenital scoliosis. Methods The data of 28 congenital scoliosis patients with balanced double hemivertebrae were retrospectively analyzed from January 2016 to June 2020. The mean age of the patients was 3.4 years. There were 16 males and 12 females. Segmental Cobb’s angle, thoracic kyphosis( T5-12), thoracolumbar kyphosis( T10-L2),sacral inclination, pelvic tilt, lumbar lordosis, cranial/caudal compensatory curve, coronal/sagittal plane balance were recorded through long cassette spinal radiographs. The deformity of anterior vertebrae and posterior lamina, ribs and intraspinal structure were recorded through computerized tomography and magnetic resonance imaging. Spinal deformity was classified into 4 types according to the position of hemivertebrae. Type 1: both in thoracic spine;Type 2:lumbosacral vertebrae and lumbar spine;Type 3: thoracic spine and lumbosacral vertebrae;Type 4: thoracic and cervical region. The indexes of different deformity types were compared. Results The distribution of hemivertebrae included 2 in C_(1-7), 8 in T_(1-5), 18 in T_(6-12), and 28 in L_(1)-S_(1), indicating that hemivertebrae was more common in lumbar( 50.0%) and lower thoracic region( 32.1%). Semi-segmented hemivertebrae was most common( 51.8%), and 24 hemivertebraes were seen in the thoracolumbar( 42.9%). Hemivertebraes were separated by a mean of 3.5 normal vertebrae. Most anterior anomalies of the vertebrae along with the corresponding posterior component was unison( 82.1%). There were 7 cases with type 1 deformity, 9 cases with type 2 deformity, 10 cases with type 3 deformity, and 2 cases with type 4 deformity. The cranial and caudal segmental Cobb’s angle was( 34.7 ± 7.5) ° and( 34.7 ± 9.6) °respectively( t = 0.005, P = 0.996). Patients with different deformity types showed no significant differences in segmental Cobb’s angle, cranial compensatory curve, balance of coronal/sagittal plane, sacral inclination, pelvic tilt, thoracic kyphosis( P > 0.05). The caudal compensatory curve, lumbar lordosis and thoracolumbar kyphosis were significantly lower in patients with type 2 deformity. Five patients complicated with rib and adjacent vertebral deformity, central canal expansion or spina bifida. Conclusions The deformity of balanced double hemivertebrae is complicated. Most hemivertebrae distributes in lumbar and lower thoracic region. The influence causing by vertebrae deformity is more obvious in sagittal plane than that in coronal plane.