Preoperative supine pelvic incidence predicts standing pelvic incidence following S2AI fixation in patients with adult spinal deformity: a prospective study.

STUDY DESIGN: A prospective study. OBJECTIVE: The aim of this study was to investigate the PI change in different postures and before and after S2­alar­iliac (S2AI) screw fixation, and to investigate whether pre-op supine PI could predict post-op standing PI. Previous studies have reported PI may change with various positions. Some authors postulated that the unexpected PI change in ASD patients could be due to sacroiliac joint laxity, S2-alar-iliac (S2AI) screw placement, or aggressive sagittal cantilever technique. However, there was a lack of investigation on how to predict post-op standing PI when making surgical strategy. METHODS: A prospective case series of ASD patients undergoing surgical correction with S2AI screw placement was conducted. Full-spine X-ray films were obtained at pre-op standing, pre-op supine, pre-op prone, as well as post-op standing postures. Pelvic parameters were measured. Spearman correlation analysis was used to determine relationships between each parameter. RESULTS: A total of 83 patients (22 males, 61females) with a mean age of 58.4 ± 9.5 years were included in this study. Pre-op standing PI was significantly lower than post-op standing PI (p = 0.004). Pre-op prone PI was significantly lower than post-op standing PI (p = 0.001). By contrast, no significant difference was observed between pre-op supine and post-op standing PI (p = 0.359) with a mean absolute difference of 2.2° ± 1.9°. Correlation analysis showed supine PI was significantly correlated with post-op standing PI (r = 0.951, p < 0.001). CONCLUSION: This study revealed the PI changed after S2AI screw fixation. The pre-op supine PI can predict post-op standing PI precisely, which facilitates to provide correction surgery strategy with a good reference for ideal sagittal alignment postoperatively.

The role of paraspinal muscle degeneration in coronal imbalance in patients with degenerative scoliosis.

Background: Coronal imbalance in degenerative scoliosis is common and is highly correlated with health-related quality of life. Paraspinal muscle is critical to spine stability, but little is known about its contribution to coronal imbalance in degenerative scoliosis. This study aims to investigate the relationship between paraspinal muscle (PSM) degeneration and coronal imbalance in patients with degenerative scoliosis (DS). Methods: This is a retrospective cohort study. A total of 117 patients with DS were retrospectively reviewed. Parameters of PSM (bilateral cross-sectional area, CSA; fat infiltration rate, FI%) at the apical disc and adjacent levels were quantitatively evaluated using MRI. Standing whole-spine radiograph was used to evaluate the coronal (Cobb angle, CA; coronal balance distance, CBD) and sagittal (thoracic kyphosis, TK; lumbar lordosis, LL; sagittal vertical axis, SVA) parameters. Patients were divided into 3 groups: coronal balanced (Type A), coronal imbalanced shifting to concavity (Type B), and coronal imbalanced shifting to convexity (Type C). Results: Based on our criteria, 56 patients were assigned to Type A, 34 patients to Type B, and 27 patients to Type C. There was no significant difference on the sagittal profiles and CSA between the groups. However, Type A showed significantly lower FI% than Type B and Type C on both concavity and convexity (Concave side: Type A vs. Type B vs. Type C, 30.8±8.1 vs. 45.1±7.7 vs. 38.7±12.5, P=0.001; Convex side: Type A vs. Type B vs. Type C, 32.6±10.9 vs. 46.3±7.3 vs. 40.7±11.8, P=0.004). Specifically, Cobb angle was negatively correlated with CSA, mainly at convexity (R=-0.415, P=0.008). Similarly, the increase of CBD significantly correlated with FI% at concavity (R=0.491, P=0.001) and convexity (R=0.354, P=0.025). Conclusions: DS patients with coronal imbalance demonstrated a worse PSM degeneration when compared with those without coronal imbalance. Besides, PSM degeneration strongly correlated with coronal imbalance, which implies that PSM degeneration may contribute to the coronal imbalance in patients with DS.

Dynamic change of pelvic incidence after long fusion to pelvis with S2-alar-iliac screw: a 2-year follow-up study.

INTRODUCTION: Pelvic incidence (PI) is a key morphological parameter that reflects the relation between the sacrum and iliac wings. It is well accepted that PI remains constant after reaching maturity. However, recent studies indicated that PI might be altered after lumbosacral fusion. Additionally, it remains uncertain on the long-term influence of long fusion to pelvis with S2-alar-iliac screw on PI in patients with adult spinal deformity (ASD). STUDY DESIGN: A retrospective study. OBJECTIVE: To investigate whether and how PI would change during the follow-up in ASD patients who underwent S2AI fixation and to identify factors associated with the change in PI. METHODS: We retrospectively reviewed all ASD patients who underwent spinal surgery using S2AI screws between November 2014 and January 2017 at our institution. Patients with minimum follow-up of two years were included. The following sagittal radiographic parameters were measured: PI, Lumbar lordosis (LL), pelvic tilt (PT), PI-LL, sagittal vertical axis (SVA) at pre-op, post-op and 2-year follow-up. According to the changes in PI at immediate post-operation, patients were classified into two groups; Group A: Changes of PI less than or equal 5° and Group B: Changes of PI greater than 5°. RESULTS: A total of 82 ASD patients (Group A: 32, Group B: 50; mean age of 53.5 ± 12.6 years) with a mean follow-up period of 30.2 ± 9.2 months were included in this study. At immediate post-operation, Group A showed no significant change in PI (45.7° ± 11.4° to 45.3° ± 11.2°, p = 0.749); while Group B had a significant decrease in PI (51.6° ± 14.5° to 40.9° ± 14.0°, p < 0.001). At the last follow-up, 48% patients (24/50) in Group B had a significant increase in PI (32.8° ± 6.4° to 45.8° ± 11.2°, p < 0.001). Intergroup analysis showed that ΔPI, post-op PI, post-op PT and age were significantly different between both groups. In addition, pre-op PI, post-op PI, post-op PT, post-op PI-LL were significantly correlated with ΔPI at last follow-up. Also, logistic regression analysis showed that post-op PI was the associated risk factor (OR = 0.865, p = 0.024) for PI-LL mismatch. CONCLUSION: Our study showed that PI decreased in more than half of ASD patients immediately after spinal surgery using S2AI screws. Approximately 48% of them were able to recover during the 2-year follow-up. Lower pre-op PI, post-op PI and PT were found to be strongly associated with the return of PI. Thus, these current findings indicated that patients with a high PI at pre-operation should not be over-corrected to avoid PI-LL mismatch postoperatively.

DrugCVar: a platform for evidence-based drug annotation for genetic variants in cancer.

MOTIVATION: Targeted therapy for cancer-related genetic variants is critical for precision medicine. Although several databases including The Clinical Interpretation of Variants in Cancer (CIViC), The Oncology Knowledge Base (OncoKB), The Cancer Genome Interpreter (CGI) and My Cancer Genome (MCG) provide clinical interpretations of variants in cancer, the clinical evidence was limited and miscellaneous. In this study, we developed the DrugCVar database, which integrated our manually curated cancer variant-drug targeting evidence from literature and the interpretations from the public resources. RESULTS: In total, 7830 clinical evidences for cancer variant-drug targeting were integrated and classified into 10 evidence tiers. Searching and browsing functions were provided for quick queries of cancer variant-drug targeting evidence. Also, batch annotation module was developed for user-provided massive genetic variants in various formats. Details, such as the mutation function, location of the variants in gene and protein structures and mutation statistics of queried genes in various tumor types, were also provided for further investigations. Thus, DrugCVar could serve as a comprehensive annotation tool to interpret potential drugs for cancer variants especially the massive ones from clinical cancer genomics studies. AVAILABILITY AND IMPLEMENTATION: The database is available at http://drugcvar.omicsbio.info. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

The prognosis and recovery of major postoperative neurological deficits after corrective surgery for scoliosis : an analysis of 65 cases at a single institution.

AIMS: The outcome following the development of neurological complications after corrective surgery for scoliosis varies from full recovery to a permanent deficit. This study aimed to assess the prognosis and recovery of major neurological deficits in these patients, and to determine the risk factors for non-recovery, at a minimum follow-up of two years. METHODS: A major neurological deficit was identified in 65 of 8,870 patients who underwent corrective surgery for scoliosis, including eight with complete paraplegia and 57 with incomplete paraplegia. There were 23 male and 42 female patients. Their mean age was 25.0 years (SD 16.3). The aetiology of the scoliosis was idiopathic (n = 6), congenital (n = 23), neuromuscular (n = 11), neurofibromatosis type 1 (n = 6), and others (n = 19). Neurological function was determined by the American Spinal Injury Association (ASIA) impairment scale at a mean follow-up of 45.4 months (SD 17.2). the patients were divided into those with recovery and those with no recovery according to the ASIA scale during follow-up. RESULTS: The incidence of major deficit was 0.73%. At six-month follow-up, 39 patients (60%) had complete recovery and ten (15.4%) had incomplete recovery; these percentages improved to 70.8% (46) and 16.9% (11) at follow-up of two years, respectively. Eight patients showed no recovery at the final follow-up. The cause of injury was mechanical in 39 patients and ischaemic in five. For 11 patients with misplaced implants and haematoma formation, nine had complete recovery. Fisher's exact test showed a significant difference in the aetiology of the scoliosis (p = 0.007) and preoperative deficit (p = 0.016) between the recovery and non-recovery groups. A preoperative deficit was found to be significantly associated with non-recovery (odds ratio 8.5 (95% confidence interval 1.676 to 43.109); p = 0.010) in a multivariate regression model. CONCLUSION: For patients with scoliosis who develop a major neurological deficit after corrective surgery, recovery (complete and incomplete) can be expected in 87.7%. The first three to six months is the time window for recovery. In patients with misplaced implants and haematoma formation, the prognosis is satisfactory with appropriate early intervention. Patients with a preoperative neurological deficit are at a significant risk of having a permanent deficit. Cite this article: Bone Joint J 2022;104-B(1):103-111.

Determining the association between the radiographic parameters and the SRS-22 scores in Chinese female patients with adolescent idiopathic scoliosis: does curve pattern matter?

Background: The Scoliosis Research Society (SRS)-22 outcomes have been shown to be correlated with radiographic parameter of adolescent idiopathic scoliosis (AIS). A recent study suggested that curve patterns might play a role in assessing the influence of deformity on patient's reported outcomes. The aim of this study was to examine the relationship between radiographic parameters and SRS-22 questionnaire outcomes in female patients with adolescent AIS among the Chinese population based on five curve patterns.Patients and Methods: The radiographic data and SRS-22 questionnaires of 259 female AIS patients were reviewed. Radiographic measurements included: Cobb angle of the major curve, T1 tilt angle, apical vertebral rotation, apical vertebral translation (AVT), thoracic kyphosis, and lumbar lordosis. Curve patterns included single thoracic (T), single thoracolumbar/lumbar (TL), double thoracic (DT), double major (DM), and triple major (TM). The correlation between radiographic measurements and each domain in SRS-22 was determined by Pearson's correlation coefficient.Results: The curve magnitude and AVT of the major curve were found to be significantly correlated with the self-image domain in all cases (Cobb angle: r = -0.426, p = 0.002; AVT: r = -0.281, p=0.006) and in all curve patterns except for TM. Compared to other groups, the TM group had a significantly larger major curve than the DT group and TL group (p ≤ 0.004). In TM group, the self-image scores were lower than TL group (p =0.018), and the function scores were lower than that in T, TL (p < 0.001) and DM groups (p =0.013). In the DT group, the T1 tilt was significantly correlated with the self-image domain (r = -0.376, p =0.004). In the T group, coronal curve magnitude was significantly correlated with function domain (r = -0.397, p < 0.001).Conclusion: Our findings suggested curve patterns should be considered in evaluating the correlations between radiographic parameters and SRS-22 outcomes in patients with AIS.