Jeffrey L. Gum

Defining Spino-pelvic Alignment Thresholds: Should Operative Goals in Adult Spinal Deformity Surgery Account for Age?

Study Design. Retrospective review of prospective, multicenter database. Objective. The aim of the study was to determine age-specific spino-pelvic parameters, to extrapolate age-specific Oswestry Disability Index (ODI) values from published Short Form (SF)-36 Physical Component Score (PCS) data, and to propose age-specific realignment thresholds for adult spinal deformity (ASD). Summary of Background Data. The Scoliosis Research Society-Schwab classification offers a framework for defining alignment in patients with ASD. Although age-specific changes in spinal alignment and patient-reported outcomes have been established in the literature, their relationship in the setting of ASD operative realignment has not been reported. Methods. ASD patients who received operative or nonoperative treatment were consecutively enrolled. Patients were stratified by age, consistent with published US-normative values (Norms) of the SF-36 PCS (<35, 35–44, 45–54, 55–64, 65–74, >75  y old). At baseline, relationships between between radiographic spino-pelvic parameters (lumbar-pelvic mismatch [PI-LL], pelvic tilt [PT], sagittal vertical axis [SVA], and T1 pelvic angle [TPA]), age, and PCS were established using linear regression analysis; normative PCS values were then used to establish age-specific targets. Correlation analysis with ODI and PCS was used to determine age-specific ideal alignment. Results. Baseline analysis included 773 patients (53.7 y old, 54% operative, 83% female). There was a strong correlation between ODI and PCS (r = 0.814, P < 0.001), allowing for the extrapolation of US-normative ODI by age group. Linear regression analysis (all with r > 0.510, P < 0.001) combined with US-normative PCS values demonstrated that ideal spino-pelvic values increased with age, ranging from PT = 10.9 degrees, PI−LL = −10.5 degrees, and SVA = 4.1 mm for patients under 35 years to PT = 28.5 degrees, PI−LL = 16.7 degrees, and SVA = 78.1 mm for patients over 75 years. Clinically, older patients had greater compensation, more degenerative loss of lordosis, and were more pitched forward. Conclusion. This study demonstrated that sagittal spino-pelvic alignment varies with age. Thus, operative realignment targets should account for age, with younger patients requiring more rigorous alignment objectives. Level of Evidence: 3

SRS22R Appearance Domain Correlates Most With Patient Satisfaction After Adult Deformity Surgery to the Sacrum at 5-year Follow-up.

Study Design. Longitudinal cohort. Objective. To evaluate the relationship between Scoliosis Research Society-22R (SRS22-R) domains and satisfaction with management in patients who underwent surgical correction for adult spine deformity. Summary of Background Data. The SRS-22R is used to measure clinical outcomes in adult spine deformity patients. The relationship between patient satisfaction and SRS-22R domain scores, the Oswestry Disability Index (ODI) and radiographical parameters has not been reported at 5-year follow-up. Methods. 135 patients with adult spinal deformity at a single institution who underwent a posterior spinal fusion of 5 levels or more to the sacrum and had complete SRS-22R pre- and minimum 5-year postoperative were identified. Wilcoxon tests were used to compare preoperative and 5-year postoperative scores. Spearman correlations were used to evaluate associations between the 5-year SRS-22R Satisfaction score and changes in SRS-22R domain scores, SubScore (SRS-22R Total—Satisfaction), ODI, and radiographical parameters. Results. There were 125 females and 10 males with a mean BMI of 26.6 kg/m2 and mean age of 53.6 years. There were 74 primary and 61 revision surgeries with a mean 9.9 levels fused and mean follow-up of 67 months. There was a statistically significant improvement between paired pre- and 5-year postop SRS-22R domain scores and most radiographical parameters, commonly P ⩽ 0.001. The majority of patients had an SRS-22R Satisfaction score of 3.0 or more (88%) or 4.0 or more (67%), consistent with a moderate ceiling effect. Correlations for SRS-22R domain scores were all statistically significant and either weak [Mental (0.26), Activity (0.27), Pain (0.35), or moderate (Appearance (0.59))]. SRS-22R SubScore (0.54) and ODI (0.43) also had a moderate correlation. Correlations for all radiographical and operative parameters were either very weak or weak. Conclusion. SRS-22R Appearance, SubScore, and ODI correlate most with patient satisfaction in adult deformity patients undergoing 5 or more level fusion to the sacrum at 5-year follow-up. Level of Evidence: 2

Dedicated Spine Measurement Software Quantifies Key Spino-Pelvic Parameters More Reliably Than Traditional Picture Archiving and Communication Systems Tools.

Study Design. Measurement reliability study of adult spinal deformity (ASD) patient radiographs using intraclass correlation coefficients (ICC) and variance. Objective. The aim of the study was to compare picture archiving and communication systems (PACS) to dedicated spine measurement software (SMS). Summary of Background Data. Accurate radiographic measurement of sagittal alignment is essential for evaluating ASD. PACS measurements often necessitate rudimentary techniques and estimations of anatomic landmarks and angles. Though SMS has been studied and validated, no studies directly compare PACS to SMS. Methods. Eleven independent observers (7 spine surgeons, 4 researchers) digitally measured 20 ASD radiographs for pelvic incidence (PI), pelvic tilt (PT), lumbar lordosis (LL), PI-LL, thoracic kyphosis (TK), and sagittal vertical axis (SVA). Round 1 used PACS basic line/angle tools; Round 2 used a validated SMS that automatically calculates spino-pelvic parameters from 6 user-identified landmarks. Means, coefficient of variance (CV), and intraclass correlation coefficients (ICC) were analyzed. Results. PACS measurements were significantly greater than SMS (PI, PT, PI-LL: P < 0.0001), though within clinical and measurement margins of error. Excluding TK, the variations in measurement (CV) were significantly greater for PACS (14–34%) vs. SMS (11–23%). Reliability was greater in SMS than PACS for PI, PT, PI-LL, LL, and SVA. The greatest differences in intraclass correlation coefficients (ICC) between PACS and SMS were in PI (PACS: 0.647; SMS: 0.810) and PI-LL (PACS: 0.921; SMS: 0.970). Among surgeons, the differences between PACS and SMS were augmented, and SMS had higher intraclass correlation coefficients (ICC) than PACS for all parameters (mean intraclass correlation coefficients [ICC] 0.931 vs. 0.861). Among surgeons, PI had the lowest reliability (PACS: 0.505; SMS: 0.752) and SVA had the highest (PACS: 0.985; SMS: 0.994). Conclusion. SMS provides significantly more reliable measurements than PACS, especially among surgeons. Consistent use of SMS in the evaluation and surgical planning of ASD patients appears necessary given the significant differences in values, variance, and reliability between PACS and SMS. Level of Evidence: 3

The Health Impact of Adult Cervical Deformity in Patients Presenting for Surgical Treatment: Comparison to United States Population Norms and Chronic Disease States Based on the EuroQuol-5 Dimensions Questionnaire

BACKGROUND: Although adult cervical spine deformity (ACSD) is associated with pain and disability, its health impact has not been quantified in comparison to other chronic diseases. OBJECTIVE: To perform a comparative analysis of the health impact of symptomatic ACSD to US normative and chronic disease values using EQ‐5D (EuroQuol‐5 Dimensions questionnaire) scores. METHODS: ACSD patients presenting for surgical treatment were identified from a prospectively collected multicenter database. Baseline demographics and EQ‐5D scores were collected and compared with US normative and disease state values. RESULTS: Of 121 ACSD patients, 115 (95%) completed the EQ‐5D (60% women, mean age 61 years, previous spine surgery in 44%). Diagnoses included kyphosis with mid‐cervical (63.4%), cervico‐thoracic (23.5%), or thoracic (8.7%) apex and primary coronal deformity (4.3%). The mean ACSD EQ‐5D index was 0.511 (standard definition = 0.224), which is 34% below the bottom 25th percentile (0.780) for similar age‐ and gender‐matched US normative populations. Mean ACSD EQ‐5D index values were worse than the bottom 25th percentile for several other disease states, including chronic ischemic heart disease (0.708), malignant breast cancer (0.708), and malignant prostate cancer (0.708). ACSD mean index values were comparable to the bottom 25th percentile values for blindness/low vision (0.543), emphysema (0.508), renal failure (0.506), and stroke (0.463). EQ‐5D scores did not significantly differ based on cervical deformity type (P = .66). CONCLUSION: The health impact of symptomatic ACSD is substantial, with negative impact across all EQ‐5D domains. The mean ACSD EQ‐5D index was comparable to the bottom 25th percentile values for blindness/low vision, emphysema, renal failure, and stroke.

Conflicting calculations of pelvic incidence and pelvic tilt secondary to transitional lumbosacral anatomy (lumbarization of S-1): case report

Advancements in the understanding of adult spinal deformity have led to a greater awareness of the role of the pelvis in maintaining sagittal balance and alignment. Pelvic incidence has emerged as a key radiographic measure and should closely match lumbar lordosis. As proper measurement of the pelvic incidence requires accurate identification of the S-1 endplate, lumbosacral transitional anatomy may lead to errors. The purpose of this study is to demonstrate how lumbosacral transitional anatomy may lead to errors in the measurement of pelvic parameters. The current case highlights one of the potential complications that can be avoided with awareness. The authors report the case of a 61-year-old man who had undergone prior lumbar surgeries and then presented with symptomatic lumbar stenosis and sagittal malalignment. Radiographs showed a lumbarized S-1. Prior numbering of the segments in previous surgical and radiology reports led to a pelvic incidence calculation of 61°. Corrected numbering of the segments using the lumbarized S-1 endplate led to a pelvic incidence calculation of 48°. Without recognition of the lumbosacral anatomy, overcorrection of the lumbar lordosis might have led to negative sagittal balance and the propensity to develop proximal junction failure. This case illustrates that improper identification of lumbosacral transitional anatomy may lead to errors that could affect clinical outcome. Awareness of this potential error may help improve patient outcomes.

Impact of poor mental health in adult spinal deformity patients with poor physical function: a retrospective analysis with a 2-year follow-up.

OBJECTIVE Mental disease burden can have a significant impact on levels of disability and health-related quality of life (HRQOL) measures. Therefore, the authors investigated the significance of mental health status in adults with spinal deformity and poor physical function. METHODS A retrospective analysis of a prospective multicenter database of 365 adult spinal deformity (ASD) patients who had undergone surgical treatment was performed. Health-related QOL variables were examined preoperatively and at the 2-year postoperative follow-up. Patients were grouped by their 36-Item Short Form Health Survey mental component summary (MCS) and physical component summary (PCS) scores. Both groups had PCS scores ≤ 25th percentile for matched norms; however, the low mental health (LMH) group consisted of patients with an MCS score ≤ 25th percentile, and the high mental health (HMH) group included patients with an MCS score ≥ 75th percentile. RESULTS Of the 264 patients (72.3%) with a 2-year follow-up, 104 (28.5%) met the inclusion criteria for LMH and 40 patients (11.0%) met those for HMH. The LMH group had a significantly higher overall rate of comorbidities, specifically leg weakness, depression, hypertension, and self-reported neurological and psychiatric disease processes, and were more likely to be unemployed as compared with the HMH group (p < 0.05 for all). The 2 groups had similar 2-year postoperative improvements in HRQOL (p > 0.05) except for the greater improvements in the MCS and the Scoliosis Research Society-22r questionnaire (SRS-22r) mental domain (p < 0.05) in the LMH group and greater improvements in PCS and SRS-22r satisfaction and back pain domains (p < 0.05) in the HMH group. The LMH group had a higher rate of reaching a minimal clinically important difference (MCID) on the SRS-22r mental domain (p < 0.01), and the HMH group had a higher rate of reaching an MCID on the PCS and SRS-22r activity domain (p < 0.05). On multivariable logistic regression, having LMH was a significant independent predictor of failure to reach an MCID on the PCS (p < 0.05). At the 2-year postoperative follow-up, 14 LMH patients (15.1%) were categorized as HMH. Two LMH patients (2.2%), and 3 HMH patients (7.7%) transitioned to a PCS score ≥ 75th percentile for age- and sex-matched US norms (p < 0.01). CONCLUSIONS While patients with poor mental and physical health, according to their MCS and PCS scores, have higher medical comorbidity and unemployment rates, they still demonstrate significant improvements in HRQOL measurements postoperatively. Both LMH and HMH patient groups demonstrated similar improvements in most HRQOL domains, except that the LMH patients had difficulties in obtaining improvements in the PCS domain.

Does Planned Staging for Posterior-Only Vertebral Column Resections in Spinal Deformity Surgery Increase Perioperative Complications?

STUDY DESIGN Propensity-matched case control. OBJECTIVES To compare the perioperative complication rate between single- and two-stage posterior-only VCRs (2-pVCR). A vertebral column resection (VCR) for severe spinal deformity is a technically challenging and lengthy procedure with a potentially high complication rate. Planned staging has an advantage of distributing operative time into 2 smaller, more manageable, intervals. METHODS Adult and pediatric spinal deformity patients undergoing a VCR were retrospectively identified from a single institutions surgical database from 1985 to 2013. Propensity scoring was used to match 2-pVCR and single-staged patients. Each group was matched for 15 preoperative risk factors including demographic, operative, and radiographic characteristics. Perioperative complications were defined as occurring within 2 months of initial surgery. Additionally, a binary logistic regression analysis was performed with complications as the outcome. RESULTS A total of 183 consecutive patients were identified as undergoing a VCR, with 172 meeting the inclusion criteria (posterior-only). Forty-four patients underwent planned 2-pVCR whereas 124 had a single-staged VCR. Consistent with propensity-matching, no statistically significant difference between the single- and 2-pVCR cohorts existed for all matching parameters, except pulmonary function tests. There was no significant difference (p =.290) between complication rates for single-stage (12/35; 34%) and 2-pVCR (8/35; 23%) patients. Stepwise binary logistic regression analysis showed that age (p =.014; OR = 0.94, CI = 0.89-0.99) and body mass index (p =.030; OR = 1.13 CI = 1.01-1.26) influenced the occurrence of a complication. CONCLUSION Planned staging of posterior-only VCRs does not increase the occurrence of perioperative complications in adult and pediatric spinal deformity patients. LEVEL OF EVIDENCE III (Propensity-matched case control).STUDY DESIGN Propensity-matched case control. OBJECTIVES To compare the perioperative complication rate between single- and two-stage posterior-only VCRs (2-pVCR). SUMMARY OF BACKGROUND DATA A vertebral column resection (VCR) for severe spinal deformity is a technically challenging and lengthy procedure with a potentially high complication rate. Planned staging has an advantage of distributing operative time into 2 smaller, more manageable, intervals. METHODS Adult and pediatric spinal deformity patients undergoing a VCR were retrospectively identified from a single institutions surgical database from 1985 to 2013. Propensity scoring was used to match 2-pVCR and single-staged patients. Each group was matched for 15 preoperative risk factors including demographic, operative, and radiographic characteristics. Perioperative complications were defined as occurring within 2 months of initial surgery. Additionally, a binary logistic regression analysis was performed with complications as the outcome. RESULTS A total of 183 consecutive patients were identified as undergoing a VCR, with 172 meeting the inclusion criteria (posterior-only). Forty-four patients underwent planned 2-pVCR whereas 124 had a single-staged VCR. Consistent with propensity-matching, no statistically significant difference between the single- and 2-pVCR cohorts existed for all matching parameters, except pulmonary function tests. There was no significant difference (p = .290) between complication rates for single-stage (12/35; 34%) and 2-pVCR (8/35; 23%) patients. Stepwise binary logistic regression analysis showed that age (p = .014; OR = 0.94, CI = 0.89-0.99) and body mass index (p = .030; OR = 1.13 CI = 1.01-1.26) influenced the occurrence of a complication. CONCLUSION Planned staging of posterior-only VCRs does not increase the occurrence of perioperative complications in adult and pediatric spinal deformity patients. LEVEL OF EVIDENCE III (Propensity-matched case control).

Cell Saver for Adult Spinal Deformity Surgery Reduces Cost

STUDY DESIGN Retrospective cohort. OBJECTIVES To determine if the use of cell saver reduces overall blood costs in adult spinal deformity (ASD) surgery. Recent studies have questioned the clinical value of cell saver during spine procedures. METHODS ASD patients enrolled in a prospective, multicenter surgical database who had complete preoperative and surgical data were identified. Patients were stratified into (1) cell saver available during surgery, but no intraoperative autologous infusion (No Infusion group), or (2) cell saver available and received autologous infusion (Infusion group). RESULTS There were 427 patients in the Infusion group and 153 in the No infusion group. Patients in both groups had similar demographics. Mean autologous infusion volume was 698 mL. The Infusion group had a higher percentage of EBL relative to the estimated blood volume (42.2%) than the No Infusion group (19.6%, p < .000). Allogeneic transfusion was more common in the Infusion group (255/427, 60%) than the No Infusion group (67/153, 44%, p = .001). The number of allogeneic blood units transfused was also higher in the Infusion group (2.4) than the No Infusion group (1.7, p = .009). Total blood costs ranged from

Orientation of the Upper-Most Instrumented Segment Influences Proximal Junctional Disease Following Adult Spinal Deformity Surgery.

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Potential of predictive computer models for preoperative patient selection to enhance overall quality-adjusted life years gained at 2-year follow-up: a simulation in 234 patients with adult spinal deformity

2,146 in the No Infusion group and from