Abstract Background context Spine surgery is usually associated with large amount of blood loss, necessitating blood transfusions. Blood loss-associated morbidity can be because of direct risks, such ...as hypotension and organ damage, or as a result of blood transfusions. The antifibrinolytic, tranexamic acid (TXA), is a lysine analog that inhibits activation of plasminogen and has shown to be beneficial in reducing surgical blood loss. Purpose To consolidate the findings of randomized controlled trials (RCTs) investigating the use of TXA on surgical bleeding in spine surgery. Study design A metaanalysis. Study sample Randomized controlled trials investigating the effectiveness of intravenous TXA in reducing blood loss in spine surgery, compared with a placebo/no treatment group. Methods MEDLINE, Embase, Cochrane controlled trials register, and Google Scholar were used to identify RCTs published before January 2014 that examined the effectiveness of intravenous TXA on reduction of blood loss and blood transfusions, compared with a placebo/no treatment group in spine surgery. Metaanalysis was performed using RevMan 5. Weighted mean difference with 95% confidence intervals was used to summarize the findings across the trials for continuous outcomes. Dichotomous data were expressed as risk ratios with 95% confidence intervals. A p<.05 was considered statistically significant. Results Eleven RCTs were included for TXA (644 total patients). Tranexamic acid reduced intraoperative, postoperative, and total blood loss by an average of 219 mL (−322, −116, p<.05), 119 mL (−141, −98, p<.05), and 202 mL (−299, −105, p<.05), respectively. Tranexamic acid led to a reduction in proportion of patients who received a blood transfusion (risk ratio 0.67 0.54, 0.83, p<.05) relative to placebo. There was one myocardial infarction (MI) in the TXA group and one deep vein thrombosis (DVT) in placebo. Conclusions Tranexamic acid reduces surgical bleeding and transfusion requirements in patients undergoing spine surgery. Tranexamic acid does not appear to be associated with an increased incidence of pulmonary embolism, DVT, or MI.
Adult spinal deformity affects the thoracic or thoracolumbar spine throughout the ageing process. Although adolescent spinal deformities taken into adulthood are not uncommon, the most usual causes ...of spinal deformity in adults are iatrogenic flatback and degenerative scoliosis. Given its prevalence in the expanding portion of the global population aged older than 65 years, the disorder is of growing interest in health care. Physical examination, with a focus on gait and posture, along with radiographical assessment are primarily used and integrated with risk stratification indices to establish optimal treatment planning. Although non-operative treatment is regarded as the first-line response, surgical outcomes are considerably favourable. Global disparities exist in both the assessment and treatment of adults with spinal deformity across countries of varying incomes, which represents an area requiring further investigation. This Seminar presents evidence and knowledge that represent the evolution of data related to spinal deformity in adults over the past several decades.
Highlights • Sagittal analysis of the spine is not a deformity specific exercise. • Pelvic morphology is the foundation for spinal alignment. • SRS-Schwab sagittal modifiers are established targets ...for spinal realignment. • Realignment procedures should respect age-adjusted alignment targets.
Background Hip osteoarthritis often coexists with adult spinal deformity, an abnormality in which sagittal spinopelvic malalignment is present. Debate exists whether to perform spinal realignment ...correction or total hip arthroplasty first. Hip extension and pelvic tilt are important compensatory mechanisms in the setting of sagittal spinopelvic malalignment and change after spinal realignment. We performed this study to evaluate the effect that the spinal realignment surgical procedure has on acetabular anteversion. Methods This study is a retrospective review of a multicenter, prospective, consecutive database of patients with adult spinal deformity who underwent surgical spinal realignment. Only patients who already had undergone a total hip arthroplasty prior to the spinal realignment procedure were retained for analysis. Patients were excluded if they had insufficient imaging or large-head, metal-on-metal bearings or they had undergone revision total hip arthroplasty in the study period. Acetabular anteversion was calculated via the ellipse method on a standing, posterior-anterior, 90-cm radiograph with a well-centered pelvis. Anteversion was measured preoperatively and at six weeks or three months after the spinal realignment procedure. Spinopelvic parameters measured included pelvic incidence, pelvic tilt, sacral slope, lumbar lordosis, T 0005 pelvic angle, sagittal vertical axis, T1-spinopelvic inclination, and thoracic kyphosis. Results Forty-one hips (thirty-three patients) were identified. Acetabular anteversion significantly reduced (p < 0.001) after spinal correction by mean change of −4.96° (range, −22.32° to +2.36°). The change in anteversion correlated with the changes in sagittal pelvic orientation (0.828 for the pelvic tilt, −0.757 for the sacral slope, and −0.691 for the lumbar lordosis) and global spinopelvic alignment (0.579 for the sagittal vertical axis and 0.585 for the T 0005 pelvic angle). Regression analysis revealed that anteversion decreased by 1° for each of the following spinopelvic parameter changes (p < 0.001): 1.105° for spinopelvic tilt, 1.032° for sacral slope, and 3.163° for lumbar lordosis. Conclusions Patients with spinopelvic malalignment had a high prevalence of excessively anteverted acetabular components. Sagittal spinal correction following total hip arthroplasty resulted in reduced acetabular anteversion, which may have implications for stability. Changes in anteversion are most closely related to changes in pelvic tilt in an almost one-to-one ratio. Level of Evidence Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.
This article was updated on November 12, 2019, because of a previous error. On page 349, in Table VII, the column heads “2 Yr”, “Mean Change from Baseline (SE)”, “Difference in Mean Change (95% CI)”, ...and “P Value” that had been aligned with the content in the second to fourth columns have now been aligned with the content in the third to fifth columns.An erratum has been publishedJ Bone Joint Surg Am. 2019 Dec 18;101(24):e138.
BACKGROUND:The effectiveness of operative compared with nonoperative treatment at initial presentation (no prior fusion) for adult lumbar scoliosis has not, to our knowledge, been evaluated in controlled trials. The goals of this study were to evaluate the effects of operative and nonoperative treatment and to assess the benefits of these treatments to help treating physicians determine whether patients are better managed operatively or nonoperatively.
METHODS:Patients with adult symptomatic lumbar scoliosis (aged 40 to 80 years, with a coronal Cobb angle measurement of ≥30° and an Oswestry Disability Index ODI score of ≥20 or Scoliosis Research Society SRS-22 score of ≤4.0) from 9 North American centers were enrolled in concurrent randomized or observational cohorts to evaluate operative versus nonoperative treatment. The primary outcomes were differences in the mean change from baseline in the SRS-22 subscore and ODI at 2-year follow-up. For the randomized cohort, the initial sample-size calculation estimated that 41 patients per group (82 total) would provide 80% power with alpha equal to 0.05, anticipating 10% loss to follow-up and 20% nonadherence in the nonoperative arm. However, an interim sample-size calculation estimated that 18 patients per group would be sufficient.
RESULTS:Sixty-three patients were enrolled in the randomized cohort30 in the operative group and 33 in the nonoperative group. Two hundred and twenty-three patients were enrolled in the observational cohort112 in the operative group and 111 in the nonoperative group. The intention-to-treat analysis of the randomized cohort found that, at 2 years of follow-up, outcomes did not differ between the groups. Nonadherence was high in the randomized cohort (64% nonoperative-to-operative crossover). In the as-treated analysis of the randomized cohort, operative treatment was associated with greater improvement at the 2-year follow-up in the SRS-22 subscore (adjusted mean difference, 0.7 95% confidence interval (CI), 0.5 to 1.0) and in the ODI (adjusted mean difference, −16 95% CI, −22 to −10) (p < 0.001 for both). Surgery was also superior to nonoperative care in the observational cohort at 2 years after treatment on the basis of SRS-22 subscore and ODI outcomes (p < 0.001). In an overall responder analysis, more operative patients achieved improvement meeting or exceeding the minimal clinically important difference (MCID) in the SRS-22 subscore (85.7% versus 38.7%; p < 0.001) and the ODI (77.4% versus 38.3%; p < 0.001). Thirty-four revision surgeries were performed in 24 (14%) of the operative patients.
CONCLUSIONS:On the basis of as-treated and MCID analyses, if a patient with adult symptomatic lumbar scoliosis is satisfied with current spine-related health, nonoperative treatment is advised, with the understanding that improvement is unlikely. If a patient is not satisfied with current spine health and expects improvement, surgery is preferred.
LEVEL OF EVIDENCE:Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.
STUDY DESIGN.Retrospective review.
OBJECTIVE.The aim of this study was to describe thoracic kyphosis (TK) in a normal asymptomatic population and to evaluate the association between TK magnitude and ...its shape.
SUMMARY OF BACKGROUND DATA.Understanding spinal anatomy requires a three-dimensional appreciation of the spineʼs shape, morphology, and proportions. The customary definition of TK is the angle between T4 and T12. However, little is known on the actual shape of TK in adults.
METHODS.Asymptomatic volunteers were recruited; demographic data along with full-body standing radiographs were recorded. Radiographic data such as T1–12 and T4–12 angles were collected. Maximum TK and vertebral orientation/tilt were also collected, in addition to cumulative TK and Centered Kyphosis at T7. The cohort was stratified by T1–12 value (<40°, 40°–60°, and>60°) and comparisons and regressions were performed afterward.
RESULTS.One hundred nineteen subjects were included (average age 50.8 yrs, 81 female). Mean T1–12 kyphosis was 49.5°, mean T4–12 kyphosis 41.5°, and mean maximum TK was 52.6°. T1 was the most anteriorly tilted vertebra, L1 the most posteriorly tilted; T7 was horizontal, independently of T1–12 value or age. Cumulative kyphosis analysis revealed that the apex of kyphosis was located at T6-T7. Regression analysis predicting the value and the percentage of T1–7 both yielded T1–12 as a predictor (Adj. r = 0.32, Adj. r = 0.13).
CONCLUSION.Changes in kyphosis distribution in an asymptomatic population suggest that TK is not a simple circle arcwith low TK, 2/3 of the kyphosis is located in the upper part and when TK increases, the distribution of kyphosis will be symmetric around T7. It is possible to predict the amount of kyphosis in the upper part using total kyphosis value. This could help estimate preoperative compensation and predict reciprocal change.Level of Evidence3
STUDY DESIGN.Prospective multicenter study evaluating operative (OP) versus nonoperative (NONOP) treatment for adult spinal deformity (ASD).
OBJECTIVE.Evaluate correlations between spinopelvic ...parameters and health-related quality of life (HRQOL) scores in patients with ASD.
SUMMARY OF BACKGROUND DATA.Sagittal spinal deformity is commonly defined by an increased sagittal vertical axis (SVA); however, SVA alone may underestimate the severity of the deformity. Spinopelvic parameters provide a more complete assessment of the sagittal plane but only limited data are available that correlate spinopelvic parameters with disability.
METHODS.Baseline demographic, radiographical, and HRQOL data were obtained for all patients enrolled in a multicenter consecutive database. Inclusion criteria wereage more than 18 years and radiographical diagnosis of ASD. Radiographical evaluation was conducted on the frontal and lateral planes and HRQOL questionnaires (Oswestry Disability Index ODI, Scoliosis Research Society-22r and Short Form SF-12) were completed. Radiographical parameters demonstrating highest correlation with HRQOL values were evaluated to determine thresholds predictive of ODI more than 40.
RESULTS.Four hundred ninety-two consecutive patients with ASD (mean age, 51.9 yr) were enrolled. Patients from the OP group (n = 178) were older (55 vs. 50.1 yr, P < 0.05), had greater SVA (5.5 vs. 1.7 cm, P < 0.05), greater pelvic tilt (PT; 22° vs. 11°, P < 0.05), and greater pelvic incidence/lumbar lordosis PI/LL mismatch (PI-LL; 12.2 vs. 4.3; P < 0.05) than NONOP group (n = 314). OP group demonstrated greater disability on all HRQOL measures compared with NONOP group (ODI = 41.4 vs. 23.9, P < 0.05; Scoliosis Research Society score total = 2.9 vs. 3.5, P < 0.05). Pearson analysis demonstrated that among all parameters, PT, SVA, and PI-LL correlated most strongly with disability for both OP and NONOP groups (P < 0.001). Linear regression models demonstrated threshold radiographical spinopelvic parameters for ODI more than 40 to bePT 22° or more (r = 0.38), SVA 47 mm or more (r = 0.47), PI − LL 11° or more (r = 0.45).
CONCLUSION.ASD is a disabling condition. Prospective analysis of consecutively enrolled patients with ASD demonstrated that PT and PI-LL combined with SVA can predict patient disability and provide a guide for patient assessment for appropriate therapeutic decision making. Threshold values for severe disability (ODI > 40) includedPT 22° or more, SVA 47 mm or more, and PI − LL 11° or more.
STUDY DESIGN.Retrospective review of a prospective multicenter database evaluating surgical adult spinal deformity (ASD) patients.
OBJECTIVE.This study aims to identify risk factors for medical ...complications in ASD patients undergoing surgery.
SUMMARY OF BACKGROUND DATA.ASD surgery is known for its high complication rate. This study examines baseline patient characteristics for predictors of medical complications in surgical ASD patients.
METHODS.Intra and perioperative medical complications were included. Medical complications wereinfection, pneumonia, urinary tract infection, c-difficile, sepsis, stroke, delirium, deep venous thrombosis, pulmonary embolism, myocardial infarction, arrhythmia, congestive heart failure, pneumothorax, atelectasis, adult respiratory distress syndrome, bowel obstruction, ileus, and renal failure. Potential predictors were identified using univariate testing. Multivariate Poisson regression was used to determine independent predictors of medical complications. Health-related quality of life (HRQL) was measured using the Oswestry Disability Index and SF-36. Multivariate repeated measures mixed models were used to examine HRQL.
RESULTS.Four hundred forty-eight patients were included. The incidence of patients with at least one medical complication was 26.8%. Potential predictors includedage, BMI, anemia, arthritis, depression, cardiac history, hypertension, lung disease, history of PVD, Charlson Comorbidity Index, ASA, smoking, sex, and the number of years with spine problems. Independent predictors identified on multivariate logistic regression modeling included hypertension (IRR 2.43 P = 0.0001), smoking (IRR 2.49 P = 0.0001), and number of years with spine problems (IRR 1.23 P = 0.03). Despite medical complications, patients experienced significant improvements in HRQL, as measured by the SF-36 (P = 0.0001) and oswestry disability index (P = 0.0001). The rate of improvement and overall improvement compared with baseline were not statistically different than that of patients who did not experience medical complications.
CONCLUSION.Risk factors for the development of postoperative medical complications after correction of ASD include smoking, hypertension, and duration of symptoms. Patients who have one or more of these risk factors should be identified and informed during informed consent of their increased risks. They should be optimized preoperatively, and followed closely during the postoperative period.Level of Evidence3
STUDY DESIGN.A retrospective cohort.
OBJECTIVE.The aim of this study was to investigate the cervical alignment necessary for the maintenance of horizontal gaze that depends on underlying ...thoracolumbar alignment.
SUMMARY OF BACKGROUND DATA.Cervical Sagittal Curve (CC) is affected by thoracic and global alignment. Recent studies suggest large variability in normative CC ranging from lordotic to kyphotic alignment. No previous studies have assessed the effect of global spinal alignment on CC in maintenance of horizontal gaze.
METHODS.Patients without previous history of spinal surgery and able to maintain their horizontal gaze while undergoing full body imaging were included. Patients were stratified on the basis of thoracic kyphosis (TK) into (<30, 30–40, 40–50, and >50) and then by SRS-Schwab sagittal vertical axis (SVA) modifier into (posterior alignment SVA <0, aligned 0–50, and malaligned >50 mm). Cervical alignment was assessed among SVA grade in TK groups. Stepwise linear regression analysis was applied on random selection of 60% of the population. A simplified formula was developed and validated on the remaining 40%.
RESULTS.In each TK group (n = 118, 137, 125, 197), lower CC (C2-C7) was significantly more lordotic by increased Schwab SVA grade. T1 slope and cervical SVA significantly increased with increased thoracolumbar (C7-S1) SVA. Upper CC (C0-C2) and mismatch between T1 slope and CC (T1-CL) were similar. Regression analysis revealed LL minus TK (LL-TK) as an independent predictor (r = 0.640, r = 0.410) with formulaCC = 10- (LL-TK)/2. Validation revealed that the absolute difference between the predicted CC and the actual CC was 8.5°. Moreover, 64.2% of patients had their predicted C2-C7 values within 10° of the actual CC.
CONCLUSION.Cervical kyphosis may represent normal alignment in a significant number of patients. However, in patients with SVA >50 and greater thoracic kyphosis, cervical lordosis is needed to maintain the gaze. Cervical alignment can be predicted from underlying TK and lumbar lordosis, which may be clinically relevant when considering correction for thoracolumbar or cervical deformityLevel of Evidence3
Retrospective review, full-body radiographical analysis of adult patients with sagittal spinal malalignment (SSM).
To investigate the compensatory mechanisms involved in the sagittal plane of the ...body after progressive spinal sagittal malalignment and to study the impact of age on compensatory mechanism recruitment.
Patients with SSM recruit compensatory mechanisms to maintain erect posture and horizontal gaze. Mechanisms such as pelvic retroversion, knee flexion, and pelvic shift have been proposed, but how they contribute and how age affects their recruitment are poorly understood.
Retrospective review of adult patients with SSM who underwent full-standing axis stereoradiography (EOS imaging). Radiographical measurements were performed with Surgimap. Patients were categorized on the basis of the mismatch between pelvic incidence (PI) and lumbar lordosis (PI-LL). Compensatory mechanisms were normalized to each patient's PI-LL and compared by mismatch groups. In addition, patients were subcategorized into 2 age groups (≥65 and <65 yr) and compared within the same groups of mismatch.
A total of 161 patients with a mean age of 62.93 ± 12.8 years. Mean sagittal vertical axis = 62.3 ± 61.5 mm; pelvic tilt (PT) = 29.2° ± 8.4°; and PI-LL = 21.0° ± 14.9°. Mismatch groups were as follows: group 1: PI-LL 0°-10°; group 2: 10°-20°; group 3: 20°-30°; and group 4: >30°. There were significant differences between all groups with regard to thoracic kyphosis (TK), PT, knee flexion angle, and pelvic shift by analysis of variance (P < 0.001). As PI-LL increased, TK and PT contribution to the compensation cascade decreased and knee flexion angle and pelvic shift contribution increased. Patients with PI-LL of more than 30° who were older had significantly less PT and more TK than patients with similar PI-LL who were younger.
Spinopelvic mismatch is an important driver in SSM. Pelvic retroversion and flattening of TK (reduction) become exhausted with increasing mismatch, at which point there seems to be a steady transfer of compensation toward significant participation of the lower limbs. Further analysis suggests differential recruitment of these compensatory mechanisms based upon age.
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