脊柱畸形患者骨盆-下肢冠状位影像学参数的测量及其平衡代偿机制

Measurement of coronal pelvic parameters and compensation of pelvis and lower limbs in spinal deformity

目的:测量脊柱畸形患者冠状位骨盆-下肢参数,探讨骨盆-下肢在脊柱畸形冠状位序列及平衡中的代偿机制。方法:收集49例以胸腰弯/腰弯为主的青少年特发性脊柱侧凸(adolescent idiopathic scoliosis,AIS)患者和46例退行性腰椎侧凸(degenerative lumbar scoliosis,DLS)患者术前、术后和末次随访时的全脊柱X线片,在正位X线片上测量骨盆-下肢冠状位参数:骶骨倾斜角(sacral obliquity,SO)、髂嵴倾斜角(iliac obliquity,IO)、髋臼倾斜角(hip obliquity,HO),由两位脊柱外科主治医生分别测量,间隔1个月后重复测量,检验其信度。同时测量脊柱冠状位参数:冠状位失平衡距离(coronal decompensation,CD)、胸腰弯/腰弯(thoracolumbar/lumbar curve,TL/L)和腰骶弯(lumbosacral curve,LS)、骨盆-下肢弯(pelvis-leg curve,PL)。将矫形前冠状位骨盆参数与TL/L进行相关性分析,并对比其与矫形后及末次随访时的差异。结果:AIS组SO、IO、HO的观察者间信度分别为0.986、0.979、0.989,观察者内信度为0.988、0.983、0.976;DLS组观察者间信度分别为0.863、0.979、0.996,观察者内信度为0.920、0.986、0.995。矫形前,AIS组和DLS组的TL/L与SO、IO、HO均有显著相关性(r分别为0.805、0.735、0.324和0.649、0.651、0.457,P<0.05),SO与IO、HO亦有显著相关性(r分别为0.800、0.518和0.529、0.359,P<0.05)。AIS组矫形前、后及末次随访时的SO分别为4.5°±2.6°、2.3°±2.1°、3.3°±2.3°,IO分别为2.0°±1.6°、0.6°±1.8°、1.4°±1.6°,HO分别为0.5°±1.5°、-0.9°±1.8°、-0.1°±1.6°;DLS组SO分别为3.1°±3.4°、1.1°±4.3°、1.4°±3.2°,IO分别为1.2°±2.0°、-0.2°±3.1°、0.4°±2.1°,HO分别为0.5°±1.9°、-0.9°±2.9°、-0.5°±2.0°;与矫形前比较,两组矫形后SO、IO、HO均显著性减小(P<0.05);AIS末次随访时SO、IO、HO有所增加(P<0.05),DLS末次随访时SO、IO、HO均无显著性变化(P>0.05)。结论:SO、IO、HO作为简单、可靠的骨盆-下肢冠状位影像学参数可用于评价骨盆及下肢的冠状位序列;骨盆-下肢弯可延续脊柱畸形的冠状位序列并参与躯干冠状位平衡的代偿。

Objectives:To explore coronal pelvic parameters and investigate the compensation of pelvis and lower limbs in coronal spinal alignment.Methods:The X-ray images of 49 subjects with adolescent idiopathic scoliosis(AIS)and 46 subjects with degenerative lumbar scoliosis(DLS)were respectively reviewed,and all of them were with major thoracolumbar/lumbar curve.Three coronal pelvic parameters including sacral obliquity(SO),iliac obliquity(IO)and hip obliquity(HO)were measured twice at an interval of 1 month by two spinal surgeons separately in posterior-anterior X-ray.The reliability of the parameters was tested.Then coronal spinal parameters including coronal decompensation(CD),thoracolumbar/lumbar curve(TL/L),lumbosacral curve(LS)and pelvis-leg curve(PL)were measured.The correlation analysis was performed between SO,IO,HO and TL/L before operation.The differences of the 3 parameters at pre-operation,post-operation and follow-up were analysed.Results:In AIS group,for SO,IO and HO,the inter-observer reliability was 0.986,0.979 and 0.989 respectively,and the intra-observer reliability was 0.988,0.983 and 0.976 respectively.In DLS group,the inter-observer reliability of SO,IO and HO was 0.863,0.979 and 0.996,and the intra-observer reliability of those was 0.920,0.986 and 0.995.At pre-operation,the correlation between TL/L and SO,IO and HO in AIS group was 0.805,0.735 and 0.324,respectively;the correlation between SO and IO and HO was 0.800 and 0.518(P<0.05).The correlation between TL/L and SO,IO and HO in DLS group was 0.649,0.651 and 0.457;the correlation between SO and IO and HO was 0.529 and 0.359(P<0.05).In AIS group,SO was 4.5°±2.6°at pre-operation,2.3°±2.1°after operation and 3.3°±2.3°at follow-up;IO was 2.0°±1.6°,0.6°±1.8°and 1.4°±1.6°respectively;HO was 0.5°±1.5°,-0.9°±1.8°and-0.1°±1.6°.In DLS group,SO was3.1°±3.4°,1.1°±4.3°and 1.4°±3.2°;IO was 1.2°±2.0°,-0.2°±3.1°and 0.4°±2.1°;HO was 0.5°±1.9°,-0.9°±2.9°and-0.5°±2.0°.In post-operation,SO,IO and HO decreased in both groups(P<0.05).At the final follow-up,SO,IO and HO increased(P<0.05)comparing with that after operation in AIS group,while there was no significant differences(P>0.05)in DLS group.Conclusions:SO,IO and HO are reliable coronal pelvic parameters,and the 3 radiographic parameters could be used to evaluate the compensation of pelvis and lower limbs in spinal deformity.The pelvis and lower limbs act as spinal vertebrae or intervertebral discs in accordance with coronal spinal alignment.The region could be considered as a compensatory spinal curve named PL.