The factors associated with lateral curve flexibility in degenerative scoliosis have not been well documented. Disc degeneration could result in significant change in stiffness and range of motion in lateral bending films. The osteophytes could be commonly observed in degenerative spine but the relationship between osteophyte formation and curve flexibility remains controversial. The aim of the current study is to clarify if the disc degeneration and osteophyte formation were both associated with curve flexibility of degenerative scoliosis. A total of 85 patients were retrospectively analyzed. The inclusion criteria were as follow: age greater than 45 years, diagnosed as degenerative scoliosis and coronal Cobb angle greater than 20°. Curve flexibility was calculated based on Cobb angle, and range of motion (ROM) was based on disc angle evaluation. Regional disc degeneration score (RDS) was obtained according to Pfirrmann classification and osteophyte formation score (OFS) was based on Nanthan classification. Spearman correlation was performed to analyze the relationship between curve flexibility and RDS as well as OFS. Moderate correlation was found between RDS and curve flexibility with a Spearman coefficient of −0.487 (P = 0.009). Similarly, moderate correlation was observed between curve flexibility and OFS with a Spearman coefficient of −0.429 (P = 0.012). Strong correlation was found between apical ROM and OFS compared to the relationship between curve flexibility and OFS with a Spearman coefficient of −0.627 (P < 0.001). Both disc degeneration and osteophytes formation correlated with curve rigidity. The pre-operative evaluation of both features may aid in the surgical decision-making in degenerative scoliosis patients.

Study Design.: A prospective analysis. Objective.: To investigate whether the hyper-selective posterior fusion (upper instrumented vertebra [UIV] as the vertebra one level below the upper end vertebra [UEV], lower instrumented vertebra [LIV] as the lower end vertebra [LEV]) was applicable in posterior fusion of Lenke 5C adolescent idiopathic scoliosis (AIS) patients and what could be the indication of hyper-selective fusion. Summary of Background Data.: The improper UIV selection in selective fusion could lead to progressive thoracic compensatory curve, shoulder imbalance, and even coronal imbalance. However, few studies analyzed the clinical outcome of hyper-selective fusion. Methods.: A prospective analysis of 80 patients with Lenke 5C AIS who underwent selective fusion was performed. According to the relationship between UEV and UIV, the patients were divided into UEV group (UIV = UEV) and UEV-1 group (UIV = UEV-1). Radiographic parameters and the incidence of postoperative proximal decompensation were compared. The Scoliosis Research Society (SRS)-22 scores were used to evaluate clinical outcomes between two groups. Results.: Thirteen patients (27%) in UEV group and six (18.75%) in UEV-1 group showed proximal decompensation during follow-up, and the incidence was equivalent (P = 0.280). Within the UEV-1 group, the patients with proximal decompensation showed similar Risser grade, baseline thoracic Cobb angle, and main Cobb angle (P = 0.611, 0.435, 0.708, respectively). However, the baseline L-T apical vertebral translation (AVT) ratio was significantly larger in patients with proximal decompensation (P = 0.028). Meanwhile, patients with proximal decompensation in UEV group showed significantly smaller preoperative UIV translation and lumbar AVT but similar postoperative UIV tilt. Conclusion.: Hyper-selective posterior fusion strategy could be performed in Lenke 5C patients with Risser more than grade 2 and with thoracic compensatory curve over 15°. The UIV in patients with small baseline thoracic curve, represented by larger baseline lumbar-thoracic AVT ratio, should be selected as UEV to prevent proximal decompensation. Level of Evidence: 4

BACKGROUND:This study investigated the prevalence and severity of low back pain (LBP), caesarean section (C-section) rate, and the anesthesia approaches among lumbar scoliosis patients undergoing anterior correction surgery, and compared them with a healthy control cohort. MATERIAL AND METHODS:The inclusion criteria for adolescent idiopathic scoliosis (AIS) patients were: presence of lumbar scoliosis, history of 1 or more pregnancies after surgery, and underwent anterior-only surgery. Healthy women with a history of 1 pregnancy were included as the control group. We recorded the type of delivery, neonatal birth weight, and perinatal complications. The quality of life was also evaluated. RESULTS:New-onset LBP was reported in 65.6% of AIS patients, significantly higher than in the control group (p<0.001). C-section was performed in 11 scoliosis patients (34.4%) and 25 healthy controls (31.25%), and the rates were not significantly different between groups (P=0.75). No serious perinatal complications were reported in either group. General anesthesia was used for all C-section AIS patients. The rate of successful neuraxial anesthesia in the control group was significantly higher (P<0.001). CONCLUSIONS:Compared with the healthy control group, lumbar AIS patients did not experience a higher risk of perinatal complications or C-section rate after anterior surgical correction, but general anesthesia was more commonly used than neuraxial regional anesthesia. LBP was more frequently observed in the post-operative AIS patients.