METHODS: A total of 371 patients who underwent ASD surgery were enrolled. The sagittal spinopelvic parameters were measured preoperatively and at the 6-month and last follow-up, and the global alignment and proportion (GAP) score was calculated. The subjects were divided into non-MC and MCs groups, and the MCs group was further divided into rod fracture (RF), screw breakage (SB), screw dislodgement (SD) and proximal junctional kyphosis (PJK) subgroups.
RESULTS: Preoperatively, the RF group had greater thoracolumbar kyphosis (TLK) and relative upper lumbar lordosis (RULL); the SB group had the largest pelvic incidence (PI) and lumbar lordosis (LL); the SD group had the least global sagittal imbalance; and the PJK group had the highest thoracic kyphosis (TK), TLK and RULL. At the last follow-up, the RF and SB groups featured a large PI minus LL (PI-LL), while the PJK group featured a prominent TK; all the MCs subgroups had sagittal malalignment and a higher GAP score, and the SB group had the most severe cases. Logistic regressions showed that the relative spinopelvic alignment (RSA) score was correlated with RF, SB and SD, while the RSA and age scores were associated with PJK.
CONCLUSIONS: Each patient with MCs had individual characteristics in the sagittal plane following ASD surgery, which may be helpful to understand the pathophysiology of poor sagittal alignment with its subsequent MCs and guide an eventual revision strategy.
方法:共纳入371例接受ASD手术的患者。术前和6个月及最后一次随访时测量矢状脊柱骨盆参数,并计算全球比对和比例(GAP)评分。将受试者分为非MC组和MC组,MCs组进一步分为棒骨折(RF),螺钉断裂(SB),螺钉移位(SD)和近端交界性脊柱后凸(PJK)亚组。
结果:术前,RF组胸腰椎后凸(TLK)和腰椎相对上凸(RULL)较大;SB组骨盆发生率(PI)和腰椎前凸(LL)最大;SD组整体矢状失衡最小;PJK组胸椎后凸(TK)最高,TLK和RULL。在最后一次随访中,RF和SB组具有较大的PI减去LL(PI-LL),而PJK组具有突出的TK;所有MC亚组都有矢状错位和较高的GAP评分,SB组病例最严重。Logistic回归分析显示,脊柱肾盂相对比对(RSA)评分与RF相关,SB和SD,而RSA和年龄评分与PJK相关。
结论:每位患有MC的患者在ASD手术后在矢状面具有个体特征,这可能有助于了解矢状面不良与其随后的MC的病理生理学,并指导最终的修订策略。