Abstract Background Context Obesity's impact on standing sagittal alignment remains poorly understood, especially with respect to the role of the lower-limbs. Given energetic expenditure in standing, ...a complete understanding of compensation in obese patients with sagittal malalignment remains relevant. Purpose This study compares obese and non-obese patients with progressive sagittal malalignment for differences in recruitment of pelvic and lower limb mechanisms. Study Design/Setting Single center retrospective review. Patient Sample 554 patients (277 obese, 277 non-obese) identified for analysis. Outcome Measures Upper body alignment parameters: sagittal vertical axis (SVA) and T1 spino-pelvic inclination (T1SPi). Compensatory lower-limb mechanisms: pelvic translation (PS: pelvic shift), knee (KA) and ankle (AA) flexion, hip extension (SFA: sacrofemoral angle), and global sagittal angle (GSA). Methods Inclusion criteria were patients≥18 years that underwent full body stereographic x-rays. Included patients were categorized as non-obese (N-Ob: BMI<30 kg/m2 ) and obese (Ob: BMI≥30 kg/m2 ). To control for potential confounders, groups were propensity score matched by age, gender and baseline pelvic incidence (PI), and subsequently categorized by increasing spino-pelvic (PI-LL) mismatch: <10°, 10°-20°, >20°. Independent t-tests and linear regression models compared sagittal (SVA, T1SPi) and lower limb (PS, KA, AA, SFA, GSA) parameters between obesity cohorts. Results 554 patients (277 Ob, 277 N-Ob) were included for analysis, and were stratified to the following mismatch categories: <10°: n=367; 10°-20°: n=91; >20°: n=96. Ob patients had higher SVA, KA, PS and GSA compared to N-Ob (p<0.001 all). Low PI-LL mismatch Ob patients had greater SVA with lower SFA (142.22° vs. 156.66°, p=0.032), higher KA (5.22° vs. 2.93°, p=0.004) and PS (4.91 vs. -5.20 mm, p<0.001) compared to N-Ob. With moderate PI-LL mismatch, Ob patients similarly demonstrated greater SVA, KA, and PS, combined with significantly lower PT (23.69° vs. 27.14°, p=0.012). Obese patients of highest (>20°) PI-LL mismatch showed greatest forward malalignment (SVA, T1SPi) with significantly greater PS, and a concomitantly high GSA (12.86° vs. 9.67°, p=0.005). Regression analysis for lower-limb compensation revealed that increasing BMI and PI-LL predicted KA (r2 =0.234) and GSA (r2 =0.563). Conclusions With progressive sagittal malalignment, obese patients differentially recruit lower extremity compensatory mechanisms while non-obese preferentially recruit pelvic mechanisms. The ability to compensate for progressive sagittal malalignment with the pelvic retroversion is limited by obesity.
STUDY DESIGN.A retrospective review of a prospectively collected database, the Nationwide Inpatient Sample (NIS), years 2003 to 2012.
OBJECTIVES.The aim of this study was to examine trends in the ...management of scoliosis in elderly (age >75 yrs) patients from 2003 to 2012.
SUMMARY OF BACKGROUND DATA.Scoliosis incidence rises with increasing age, and age has been shown to be an independent risk factor for surgical complications in scoliosis surgery. Previous studies have displayed increasing surgical frequency on elderly scoliotic patients in the last decade, but have not investigated complications in the same years.
METHODS.ICD-9 coding identified elderly (age ≥75 yrs) patients with a primary diagnosis of scoliosis undergoing lumbar fusion or decompression. Analysis of variance (ANOVA) comparisons and linear trend analysis described changes from 2003 to 2012 in surgical invasiveness (Mirza scalelevels fused/decompressed/instrumented and by approach), intraoperative complications, and Charlson Comorbidity Index (CCI). Secondary outcome measures included cost and discharge outcomes.
RESULTS.Eight thousand one elderly patients with ASD from 2003 to 2012 were included for analysis. Fusion incidence increased on average 13.8% per year (P < 0.001), surgical invasiveness by Mirza scale increased from 2.0 in 2003 to 5.9 in 2012 (P < 0.001), and CCI increased from 0.77 to 1.44 (p < 0.001). Over the same interval, elderly patients undergoing fusion displayed overall reduction in complications (excluding anemia)—from 26.7% to 8.6% (P < 0.001); specifically, surgical complications decreased from 11.7% to 0.7% (P < 0.001) and respiratory complications decreased from 6.7% to 1.4% (P = 0.004).
CONCLUSION.From 2003 to 2012, surgical management of ASD in the elderly population increased in incidence and complexity, while number of patient comorbidities increased and in-hospital morbidity decreased. This may indicate increased willingness of surgeonʼs to operate on elderly patients, and reflect a development of overall understanding of deformity in the past decade.Level of Evidence3
Distal junctional kyphosis (DJK) is a primary concern of surgeons correcting cervical deformity. Identifying patients and procedures at higher risk of developing this condition is paramount in ...improving patient selection and care.
The present study aimed to develop a risk index for DJK development in the first year after surgery.
This is a retrospective review of a prospective multicenter cervical deformity database.
Patients over the age of 18 meeting one of the following deformities were included in the study: cervical kyphosis (C2–7 Cobb angle>10°), cervical scoliosis (coronal Cobb angle>10°), positive cervical sagittal imbalance (C2–C7 sagittal vertical axis (SVA)>4 cm or T1-C6>10°), or horizontal gaze impairment (chin-brow vertical angle>25°).
Development of DJK at any time before 1 year.
Distal junctional kyphosis was defined by both clinical diagnosis (by enrolling surgeon) and post hoc identification of development of an angle<−10° from the end of fusion construct to the second distal vertebra, as well as a change in this angle by <−10° from baseline. Conditional Inference Decision Trees were used to identify factors predictive of DJK incidence and the cut-off points at which they have an effect. A conditional Variable-Importance table was constructed based on a non-replacement sampling set of 2,000 Conditional Inference Trees. Twelve influencing factors were found; binary logistic regression for each variable at significant cutoffs indicated their effect size.
Statistical analysis included 101 surgical patients (average age: 60.1 years, 58.3% female, body mass index: 30.2) undergoing long cervical deformity correction (mean levels fused: 7.1, osteotomy used: 49.5%, approach: 46.5% posterior, 17.8% anterior, 35.7% combined). In 2 years after surgery, 6% of patients were diagnosed with clinical DJK; however, 23.8% of patients met radiographic definition for DJK. Patients with neurologic symptoms were at risk of DJK (odds ratio OR: 3.71, confidence interval CI: 0.11–0.63). However, no significant relationship was found between osteoporosis, age, and ambulatory status with DJK incidence. Baseline radiographic malalignments were the most numerous and strong predictors for DJK: (1) C2-T1 tilt>5.33 (OR: 6.94, CI: 2.99–16.14); (2) kyphosis<−50.6° (OR: 5.89, CI: 0.07–0.43); (3) C2–C7 lordosis<−12° (OR: 5.7, CI: 0.08–0.41); (4) T1 slope minus cervical lordosis>36.4 (OR: 5.6, CI: 2.28–13.57); (5) C2-C7 SVA>56.3° (OR: 5.4, CI: 2.20–13.23); and (6) C4_Tilt>56.7 (OR: 5.0, CI: 1.90–13.1). Clinically, combined approaches (OR: 2.67, CI: 1.21–5.89) and usage of Smith-Petersen osteotomy (OR: 2.55, CI: 1.02–6.34) were the most important predictors of DJK.
In a surgical cohort of patients with cervical deformity, we found a 23.8% incidence of DJK. Different procedures and patient malalignment predicted incidence of DJK up to 1 year. Preoperative T1 slope-cervical lordosis, cervical kyphosis, SVA, and cervical lordosis all strongly predicted DJK at specific cut-off points. Knowledge of these factors will potentially help direct future study and strategy aimed at minimizing this potentially dramatic occurrence.
With advances in the understanding of adult spinal deformity (ASD), more complex osteotomy and fusion techniques are being implemented with increasing frequency. Patients undergoing ASD corrections ...infrequently require extended acute care, longer inpatient stays, and are discharged to supervised care. Given the necessity of value-based health care, identification of clinical indicators of adverse discharge disposition in ASD surgeries is paramount.
Using the nationwide and surgeon-created databases, the present study aimed to identify predictors of adverse discharge disposition after ASD surgeries and view the corresponding differences in charges.
This is a retrospective analysis of patients on the National Surgical Quality Improvement Program (NSQIP) database and of cost data from Medicare PearlDiver Database.
Patients undergoing thoracolumbar surgery for correction of ASD were included in the study.
Primary analysis was performed to compare patients discharged to home with patients who either expired or were discharged to locations other than home. Secondary analysis was performed to determine the cost differences across discharge groups.
Patients on NSQIP undergoing thoracolumbar ASD-corrective surgery with a primary diagnosis of scoliosis (ICD-9 code 737.x) and over the age of 18 were isolated. Predictors (demographic, clinical, and complications) of not-home (NH; rehab or skilled nursing facility) discharge were analyzed using binary logistic regression controlling for levels fused, decompressions, osteotomies, and revisions. Average 30- and 90-day costs of care were reported in home, rehab, and skilled nursing facility discharge groups in patients undergoing 8+ level thoracolumbar fusion.
A total of 1,978 patients undergoing lumbar ASD-corrective surgery were included for analysis (average age: 59.3 years, sex: 64% female). Average length of stay was 6.58 days. On multivariate regression analysis, age over 60 years (odds ratio OR: 0.28, confidence interval CI: 0.22–0.34) and female sex (p=.003) were independent predictors of adverse discharge status. Partially dependent preoperational functional status, defined as reliance on another person to complete some activities of daily living, increased likelihood of adverse discharge disposition (OR: 0.57, CI: 0.35–0.90). Despite controlling for all clinical variables except for the ones specific to each analysis, Smith-Petersen osteotomy (OR: 0.51, CI: 0.40–0.64), interbody device placement (OR: 0.80, CI: 0.64–0.98), and fixation to the iliac (OR: 0.54, CI: 0.41–0.70) increased the likelihood of adverse discharge. Complications most associated with adverse discharge were urinary tract infections (OR: 0.34, CI: 0.21–0.57) and blood transfusions (OR: 0.42, CI: 0.34–0.52). Relative to home discharge, 30-day costs of care were +$21,061 more expensive in rehab discharges, but not different in skilled nursing facility discharges (+$5,791, p=.177). The 90-day costs of care were $23,815 in rehab discharges (p<.001), but again not different from skilled nursing facility discharges (+$6,091, p=.212).
Discharge destination to rehabilitation has a significant impact on the cost of thoracolumbar ASD surgeries. Patient selection can predict patients at higher risk of discharges to rehab or skilled nursing facility.
BACKGROUND:Estimation of skeletal maturity, classically performed using Risser sign, plays a crucial role in the treatment of AIS. Recent data, however, has shown the simplified Tanner-Whitehouse ...(Sanders) classification, based on an anteriorposterior (AP) hand radiographs, to correlate more closely to the rapid growth phase and thus curve progression. This study evaluated the interobserver and intraobserver reliability of the Sanders and Risser classifications among clinicians at different levels of training.
METHODS:Twenty AP scoliosis radiographs and 20 AP hand radiographs were randomized and distributed to 11 graders. The graders consisted of 3 orthopaedic residents, 3 spine fellows, 3 spine surgeons, and 1 radiologist. The graders were then asked to classify the radiographs according to the Sanders and Risser classifications. There were 3 rounds of grading, each done 3 weeks apart. The overall κ coefficient was then calculated for each system to evaluate the interobserver and intraobserver reliability.
RESULTS:For all graders the average κ coefficient for the interobserver and intraobserver reliability of the Sanders classification was 0.54 and 0.62, respectively, and 0.46 and 0.49 for the Risser classification. With respect to spine attendings alone, the average κ coefficient for the interobserver and intraobserver reliability of Sanders classification was 0.72 and 0.77, respectively, and 0.46 and 0.67 for the Risser classification.
CONCLUSIONS:Our study demonstrated that the Sanders classification had moderate reliability with respect to physicians at various levels of training and had good reliability with respect to attending spine surgeons. Interestingly, the Risser staging was found to have less interobserver and intraobserver reliability overall. The Sanders classification is a reliable and reproducible system and should be in the armamentarium of surgeons who treat adolescent idiopathic scoliosis.
LEVEL OF EVIDENCE:Level III.
STUDY DESIGN.Retrospective analysis of three prospectively collected databases.
OBJECTIVE.To compare perioperative outcomes in Adult Spinal Deformity (ASD) surgeries in a surgeon-run (SR-ASD) and two ...national databasesthe Nationwide Inpatient Sample (NIS) and the National Surgical Quality Improvement Program (NSQIP).
SUMMARY OF BACKGROUND DATA.Much has been learned on the treatment of ASD in the last decade with prospective multicenter collaborative research focusing on this specific condition. Nondisease specific national databases are being used for hypothesis and quality control testing on a large number of ASD patients. Their accuracy and applicability remains unevaluated.
METHODS.Patients were identified on each respective database undergoing lumbar spine fusion for ASD. Propensity score matching established cohorts of patients on each database with similar procedures being performed. Complication prevalence and relative risk was compared on the NIS and NSQIP against SR-ASD. Secondary outcome measures included hospital-stay characteristics, surgical invasiveness, patient demographics, and patient comorbidities.
RESULTS.Two hundred fifty-five patients were identified on each database 1:1:1 with similar overall surgical intensity. Querying the databases using ICD-9 codes, CPT codes, and surgeon-reports resulted in different complication incidencesoverall complication rates were 17.65% on NIS, 24.31% on NSQIP, and 68.24% on SR-ASD. The relative risk of a medical complication in SR-ASD was 1.87 (1.42–2.48) relative to NIS and 1.91 (1.44–2.54) relative to NSQIP. The relative risk of a surgical complication was 5.45 (2.69–11.05) compared with NIS and 12.05 (3.98–36.49) compared with NSQIP.
CONCLUSION.After selecting patients using the same criteria and diagnosis, NIS, NSQIP, and SR-ASD databases captured different patient populations and different complication incidences. There were total absences of certain complications contrary to usual literature rates in all three databases. Faithful reporting necessitates understanding database limitations, and careful evaluation of database strengths and weaknesses is paramount to accurate reports.Level of Evidence3
Abstract Background Context Adult spinal deformity (ASD) represents a constellation of complex mal-alignments affecting the spinal column. Corrective surgical procedures aimed at improving ASD can be ...equally challenging, and commonly require multiple index procedures and potential revisions prior to definitive management. There is a paucity of data comparing the outcomes of same-day (simultaneous) and two-day (staged) procedures for long spinal-fusions for ASD. Utilizing a large patient cohort with surgeon and patient-reported outcomes will be particularly useful in determining the utility and effect of staging long spine fusions for ASD. Purpose Compare intra-operative, peri-operative, and two-year outcomes of staged and simultaneous procedures correcting ASD. Study Design/Setting Retrospective analysis of a prospective multi-center database. Patient Sample 142 patients (71 Staged, 71 Simultaneous). Outcome Measures Primary: intra- and peri-op (6 wk) complication rates. Secondary: 2 year thoracolumbar and spino-pelvic radiographic parameters, 2 year Health Related Quality of Life changes (Oswestry Disability Index and SF-36), and 2 year complication rates Methods Inclusion criteria included ASD patients ≥18yrs with 6-wk and 2 year follow-up. Propensity score matching identified similar patients undergoing staged (STA) or simultaneous (SIM) long spine fusions based on Surgical Invasiveness, Pelvic Tilt, and SVA. Complications, HRQLs (SRS22r, SF-36, ODI), and patient characteristics were compared across and within treatment groups at follow-up with ANOVA and paired t-tests at 3 surgical stages: intra-op, peri-op (6wk), and post-op (>6wk). Results 142 patients were included (71 STA, 71 SIM). Matching staged and simultaneous groups based on degree of deformity and surgical invasiveness created two groups similar in overall correction of the surgery. STA patients underwent more ALIF and LLIF interbody procedures while SIM patients had longer fusions. Charlson Comorbidity Index and revision status were similar between groups (p>0.05). There were significantly more complications causing reoperation in STA procedures (STA: 47% SIM: 8%, p=0.021). STA had a greater number of peri-op complications requiring a return to the OR (STA: 9.9% SIM: 1.4% p=0.029). There was no difference in intra-op complications, mortality, or peri-op infection or wound complications (p>0.05). At 2 year follow-up, incidence of revision surgery was higher in STA (STA: 21.1% SIM: 8.5%, p=0.033). Conclusion Staged spinal fusions which add ALIFs and LLIFs to the procedure, compared to similar-correction simultaneous procedures, result in similar intra-operative complication incidence, but significantly higher rates of peri- and post-op complications leading to revision. Functional outcomes, radiographic parameters, and mortality were similar. This will aid surgeons in their determination of optimal treatment for such complex procedures.
Introduction
Since its introduction BMP has been utilized in populations with higher rates of malunion, such as adult spinal deformity (ASD) patients. Contradictory conclusions exist in spinal ...literature regarding the safety and efficacy of the use of BMP in this setting. Previous studies, however, did not distinguish deformity cases from spondylolisthesis or stenosis. The purpose of this study is to evaluate the safety and efficacy of BMP use in spinal fusion surgery for ASD.
Methods
166 papers were screened after database search. 40 full texts were assessed for eligibility. Five studies were included for meta-analysis. Three were comparative studies between a BMP and non-BMP group, and the other was used to supplement dose-effect analysis.
Results
The current meta-analysis found increased odds of developing radiculitis or neurological complications (OR = 2.18, 95% CI,
p
= 0.02,
i
2
= 0), but no other significant relationship between complications commonly attributed to BMP use (tumorigenesis, infections, seroma formation, or osteolysis) and BMP use. BMP patients had decreased rates of pseudarthrosis (OR = 0.23, 95% CI,
p
= 0.002,
i
2
= 0). There was an average dose of 8.75 mg/level in the 417 patients studied, lower than the advised dosage of 12 mg/level.
Conclusions
The current literature shows BMP to be a safe and effective grafting technique in the treatment of ASD. Spine surgeons may currently be using sub-optimal doses of BMP. The benefit of increasing the rate of fusion must be weighed against the increased risk of radiculitis and neurologic complications in this patient population.
Abstract
BACKGROUND
Primary drivers (PDs) of adult cervical deformity (ACD) have not been described in relation to pre- and early postoperative alignment or degree of correction.
OBJECTIVE
To define ...the PDs of ACD to understand the impact of driver region on global postoperative compensatory mechanisms.
METHODS
Primary cervical deformity driver/vertebral apex level were determined: CS = cervical; CTJ = cervicothoracic junction; TH = thoracic; SP = spinopelvic. Patients were evaluated if surgery included PD apex, based on the lowest instrumented vertebra (LIV): CS: LIV ≤ C7, CTJ: LIV ≤ T3, TH: LIV ≤ T12. Cervical and thoracolumbar alignment was measured preoperatively and 3 mo (3M) postoperatively. PD groups were compared with analysis of variance/Pearson χ2, paired t-tests.
RESULTS
Eighty-four ACD patients met inclusion criteria. Thoracic drivers (n = 26) showed greatest preoperative cervical and global malalignment against other PD: higher thoracic kyphosis, pelvic incidence-lumbar lordosis (PI-LL), T1 slope C2-T3 sagittal vertical axis (SVA), and C0-2 angle (P < .05). Differences in baseline-3M alignment changes were observed between surgical PD groups, in PI-LL, LL, T1 slope minus cervical lordosis (TS-CL), cervical SVA, C2-T3 SVA (P < .05). Main changes were between TH and CS driver groups: TH patients had greater PI-LL (4.47° vs −0.87°, P = .049), TS-CL (−19.12° vs −4.30, P = .050), C2-C7 SVA (−18.12 vs −4.30 mm, P = .007), and C2-T3 SVA (−24.76 vs 8.50 mm, P = .002) baseline-3M correction. CTJ drivers trended toward greater LL correction compared to CS drivers (−6.00° vs 0.88°, P = .050). Patients operated at CS driver level had a difference in the prevalence of 3M TS-CL modifier grades (0 = 35.7%, 1 = 0.0%, 2 = 13.3%, P = .030). There was a significant difference in 3M chin-brow vertical angle modifier grade distribution in TH drivers (0 = 0.0%, 1 = 35.9%, 2 = 14.3%, P = .049).
CONCLUSION
Characterizing ACD patients by PD type reveals differences in pre- and postoperative alignment. Evaluating surgical alignment outcomes based on PD inclusion is important in understanding alignment goals for ACD correction.
STUDY DESIGN.Retrospective review.
OBJECTIVE.Determine whether alignment or myelopathy improvement drives patient outcomes after cervical deformity (CD) corrective surgery.
SUMMARY OF BACKGROUND ...DATA.CD correction involves radiographic malalignment correction and procedures to improve motor function and pain. It is unknown whether alignment or myelopathy improvement drives patient outcomes.
METHODS.InclusionPatients with CD with baseline/1-year radiographic and outcome scores. Cervical alignment improvement was defined by improvement in Ames CD modifiers. modified Japanese Orthopaedic Association (mJOA) improvement was defined as mild 15–17, moderate 12–14, severe <12. Patient groups included those who only improved in alignment, those who only improved in mJOA, those who improved in both, and those who did not improve. Changes in quality-of-life scores (neck disability index NDI, EuroQuol-5 dimensions EQ-5D, mJOA) were evaluated between groups.
RESULTS.A total of 70 patients (62 yr, 51% F) were included. Overall preoperative mJOA score was 13.04 ± 2.35. At baseline, 21 (30%) patients had mild myelopathy, 33 (47%) moderate, and 16 (23%) severe. Out of 70 patients 30 (44%) improved in mJOA and 13 (18.6%) met 1-year mJOA minimal clinically important difference. Distribution of improvement groups16/70 (23%) alignment-only improvement, 13 (19%) myelopathy-only improvement, 18 (26%) alignment and myelopathy improvement, and 23 (33%) no improvement. EQ-5D improved in 11 of 16 (69%) alignment-only patients, 11 of 18 (61%) myelopathy/alignment improvement, 13 of 13 (100%) myelopathy-only, and 10 of 23 (44%) no myelopathy/alignment improvement. There were no differences in decompression, baseline alignment, mJOA, EQ-5D, or NDI between groups. Patients who improved only in myelopathy showed significant differences in baseline-1Y EQ-5D (baseline0.74, 1 yr:0.83, P < 0.001). One-year C2-S1 sagittal vertical axis (SVA; mJOA r = −0.424, P = 0.002; EQ-5D r = −0.261, P = 0.050; NDI r = 0.321, P = 0.015) and C7-S1 SVA (mJOA r = −0.494, P < 0.001; EQ-5D r = −0.284, P = 0.031; NDI r = 0.334, P = 0.010) were correlated with improvement in health-related qualities of life.
CONCLUSION.After CD-corrective surgery, improvements in myelopathy symptoms and functional score were associated with superior 1-year patient-reported outcomes. Although there were no relationships between cervical-specific sagittal parameters and patient outcomes, global parameters of C2-S1 SVA and C7-S1 SVA showed significant correlations with overall 1-year mJOA, EQ-5D, and NDI. These results highlight myelopathy improvement as a key driver of patient-reported outcomes, and confirm the importance of sagittal alignment in patients with CD.Level of Evidence3
