The Spine Journal 14 (2014) 1S–183S

NASS 29th Annual Meeting Proceedings

Wednesday, November 12, 20147:30 – 8:30 a.m.

Best Papers d Surgery

1. Outcomes of Operative and Nonoperative Treatment for Adult

Spinal Deformity (ASD): A Prospective, Multicenter Matched and

Unmatched Cohort Assessment with Minimum Two-Year Follow-Up

International Spine Study Group1, Justin S. Smith, MD, PhD2,

Virginie Lafage, PhD3, Christopher I. Shaffrey, MD4, Frank J. Schwab,

MD3, Richard A. Hostin, MD5, Oheneba Boachie-Adjei, MD6, Behrooz

A. Akbarnia, MD7, Eric O. Klineberg, MD8, Munish C. Gupta, MD9,

Themistocles S. Protopsaltis, MD3, Justin K. Scheer, BS10, Kai-Ming

G. Fu, MD, PhD11, Gregory M. Mundis, Jr., MD7, Khaled M. Kebaish,

MD12, Breton Line13, Han Jo Kim, MD6, Vedat Deviren, MD14, Robert

A. Hart, MD15, Douglas C. Burton, MD16, Shay Bess, MD17, Christopher

P. Ames, MD14; 1Brighton, CO, US; 2University of Virginia Health System,

Charlottesville, VA, US; 3New York University Langone Medical Center

Hospital for Joint Diseases, New York, NY, US; 4University of Virginia

Department of Neurosurgery, Charlottesville, VA, US; 5Southwest Scoliosis

Institute, Plano, TX, US; 6Hospital for Special Surgery, New York, NY, US;7San Diego Center for Spinal Disorders, La Jolla, CA, US; 8University of

California Davis School of Medicine, Sacramento, CA, US; 9University of

California Davis Orthopaedic Surgery, Sacramento, CA, US; 10University

of California San Diego, San Diego, CA, US; 11Weill Cornell Medical

College, New York, NY, US; 12Baltimore, MD, US; 13Denver, CO, US;14University of California San Francisco, San Francisco, CA, US;15Oregon Health and Science University, Portland, OR, US; 16University

of Kansas Medical Center, Kansas City, KS, US; 17Rocky Mountain

Scoliosis and Spine, Denver, CO, US

BACKGROUND CONTEXT: Adults with spinal deformity typically

present with pain and disability.

PURPOSE: Our objective was to compare outcomes for operative (op)

and nonoperative (nonop) treatment for ASD based on a prospective, mul-

ticenter patient population.

STUDY DESIGN/SETTING: Multicenter, prospective, consecutive case

series with matched and unmatched cohort analyses.

PATIENT SAMPLE: 689 ASD patients.

OUTCOME MEASURES: Baseline (BL) and minimum 2-yr health-

related quality of life (HRQL) measures including Scoliosis Research

Society Questionnaire 22r (SRS-22r), Oswestry Disability Index (ODI),

Short Form 36 Health Questionnaire (SF-36; Physical Component Score

[PCS] and Mental Component Score [MCS]), and back and leg pain nu-

meric rating scale (NRS) scores.

METHODS: This is a multicenter, prospective analysis of consecutive

ASD patients electing for either op or nonop care at enrollment. Inclusion

criteria: ageO18 yr and ASD. Propensity scores were used to match op and

nonop patients based on BL ODI, SRS-22r, maximum thoracolumbar/

lumbar Cobb angle, pelvic incidence to lumbar lordosis mismatch (PI-LL),

and leg pain NRS score.

RESULTS: 689 patients met criteria, including 286 op and 403 nonop, with

mean ages of 53 and 55 yrs, minimum 2-yr follow-up rates of 86% and 55%,

andmean follow-up of 24.7 and 24.8 months, respectively. At BL, compared

with nonop, op patients had significantly worse HRQL based on ODI,

SRS22, SF36, and leg and back pain NRS (p!0.001) and had worse deform-

ity based on pelvic tilt, PI-LL, and C7SVA (p!0.002). Before reaching min

Refer to onsite Annual Meeting presentations and postmeeting proceedings for po

reporting disclosures and FDA device/drug

2-yr follow-up 38 nonop patients converted to op treatment and were ana-

lyzed in the op group. At min 2-yr follow-up all HRQL measures assessed

significantly improved for op patients (p!0.001), but none of these meas-

ures improved significantly for nonop patients (pO0.11). 97 matched op-

nonop pairs were identified based on propensity scores. At last follow-up

the 97 matched op patients had significant improvement in all HRQL meas-

ures assessed (p!0.001), but the 97 matched nonop patients lacked signifi-

cant improvement in any of the HRQLmeasures (pO0.20). Paired op-nonop

analysis demonstrated the op patients to have significantly better HRQL

scores at follow-up for all measures assessed (p!0.001), except SF36

MCS (p50.058). Overall minor andmajor complication rates for op patients

were 53% and 40%, respectively.

CONCLUSIONS: The present study is a large prospective, multicenter

analysis of op and nonop treatment for ASD. At minimum 2-yr follow-

up, both unmatched and matched analyses demonstrated significant im-

provement in standardized HRQL measures for op patients. In contrast,

nonop treatment appears to at best maintain presenting levels of pain

and disability.

FDA DEVICE/DRUG STATUS: This abstract does not discuss or include

any applicable devices or drugs.

http://dx.doi.org/10.1016/j.spinee.2014.08.015

2. Comparison of Best versus Worst Clinical Outcomes for Adult

Spinal Deformity (ASD) Surgery: A Prospective, Multicenter

Assessment with Minimum Two-Year Follow-Up

International Spine Study Group1, Justin S. Smith, MD, PhD2, Christopher

I. Shaffrey, MD3, Virginie Lafage, PhD4, Frank J. Schwab, MD4,

Themistocles S. Protopsaltis, MD4, Eric O. Klineberg, MD5, Munish

C. Gupta, MD6, Justin K. Scheer, BS7, Richard A. Hostin, MD8, Kai-Ming

G. Fu, MD, PhD9, Han Jo Kim, MD10, Alexandra Soroceanu, MD, MPH11,

Vedat Deviren, MD12, Robert A. Hart, MD13, Douglas C. Burton, MD14,

Shay Bess, MD15, Christopher P. Ames, MD12; 1Brighton, CO, US;2University of Virginia Health System, Charlottesville, VA, US; 3University

of Virginia Department of Neurosurgery, Charlottesville, VA, US; 4New

York University Langone Medical Center Hospital for Joint Diseases, New

York, NY, US; 5University of California Davis School of Medicine,

Sacramento, CA, US; 6University of California Davis Orthopaedic

Surgery, Sacramento, CA, US; 7University of California San Diego, San

Diego, CA, US; 8Southwest Scoliosis Institute, Plano, TX, US; 9Weill

Cornell Medical College, New York, NY, US; 10Hospital for Special

Surgery, New York, NY, US; 11Dalhousie University, Halifax, NS, Canada;12University of California San Francisco, San Francisco, CA, US;13Oregon Health and Science University, Portland, OR, US; 14University

of Kansas Medical Center, Kansas City, KS, US; 15Rocky Mountain

Scoliosis and Spine, Denver, CO, US

BACKGROUND CONTEXT: Studies suggest that average clinical out-

comes are improved with surgery for selected adult spinal deformity

(ASD) patients, but these outcomes span a broad range.

PURPOSE: Our objective was to compare ASD patients with best vs

worst clinical outcomes to identify distinguishing factors.

STUDY DESIGN/SETTING: Multicenter, prospective, consecutive case

series.

PATIENT SAMPLE: 227 ASD patients.

OUTCOME MEASURES: Baseline and minimum 2-yr health-related

quality of life (HRQL) measures including Scoliosis Research Society

ssible referenced figures and tables. Authors are responsible for accurately

status at time of abstract submission.

2S Proceedings of the NASS 29th Annual Meeting / The Spine Journal 14 (2014) 1S–183S

Questionnaire 22r (SRS-22r), Oswestry Disability Index (ODI), Short

Form 36 Health Questionnaire (SF-36; Physical Component Score [PCS]

and Mental Component Score [MCS]), and back and leg pain numeric rat-

ing scale (NRS) scores

METHODS: This is a multicenter, prospective study of consecutive ASD

patients treated operatively. Inclusion criteria included: ageO18 yr, ASD

and minimum 2-yr follow-up. Best vs worst outcomes patients were com-

pared separately based on SRS-22r and ODI. Only those with baseline

SRS-22r!3.5 or ODIO30 were included to minimize floor effect. Best

and worst outcomes were defined for SRS-22r (O4.5 and!2.5) and ODI

(!15 andO50).

RESULTS: Of 227 patients, 187 had SRS-22!3.5 (25 best and 27 worst

outcomes) and 162 had ODIO30 (43 best and 51 worst outcomes). Based

on SRS-22, compared with best outcomes patients, those with worst out-

comes had greater baseline SRS-22r (p!0.0001), higher prevalence of

baseline depression (p!0.001), greater comorbidities (p50.012), greater

prevalence of prior surgery (p50.007), higher complication rate

(p50.012) and worse baseline deformity (SVA [p50.045], PI-LL mis-

match [p50.034]). The best-fit multivariate model for SRS-22r included

baseline SRS-22r (p50.033), baseline depression (p50.012) and compli-

cations (p50.030). Based on ODI, compared with best outcomes patients,

those with worst outcomes had greater baseline ODI (p!0.001), greater

baseline body mass index (BMI; p50.002), higher prevalence of baseline

depression (p!0.028), greater baseline SVA (p50.016), higher complica-

tion rate (p50.02) and greater 2-yr SVA (p!0.001) and PI-LL mismatch

(p50.042). The best-fit multivariate model for ODI included baseline

ODI (p!0.001), 2-yr SVA (p50.014) and baseline BMI (p50.037). Age

did not distinguish best vs worst outcomes for SRS-22r or ODI (pO0.1).

CONCLUSIONS: Although recent studies suggest that average clinical

outcomes are improved following surgery for selected ASD patients, these

outcomes span a broad range. In this study, baseline and perioperative fac-

tors distinguishing between the best and worst outcomes for ASD surgery

included several patient factors (baseline depression, BMI, comorbidities

and disability), as well as residual deformity (SVA), and occurrence of

complications. These findings suggest factors that may warrant greater

awareness in order to achieve optimal surgical outcomes for ASD patients.

FDA DEVICE/DRUG STATUS: This abstract does not discuss or include

any applicable devices or drugs.

http://dx.doi.org/10.1016/j.spinee.2014.08.016

3. Correlation of Cervical Sagittal Alignment Parameters on Full-

Length Spine Radiographs Compared with Dedicated Cervical

Radiographs

Casey L. Smith, MD1, Leah Y. Carreon, MD, MSc2, John R. Dimar, II,

MD3, Farah Ammous4, Steven D. Glassman, MD2; 1Grand Rapids Medical

Education Partners, Grand Rapids, MI, US; 2Norton Leatherman Spine

Center, Louisville, KY, US; 3Spine Institute, Louisville, KY, US; 4Norton

Healthcare, Inc., Louisville, KY, US

BACKGROUND CONTEXT: Recently, attention has been directed to the

impact of adult scoliosis or scoliosis treatment on the cervical spine. Several

authors have proposed a set of standardized radiographic parameters to help

evaluate the cervical spine in patients with adult spinal deformity using full-

length 36-inch radiographs. While this is the standard radiograph used to

evaluate spinal deformity, dedicated cervical spine radiographs are more

commonly used to evaluate cervical spinal pathology. In order to limit costs

and exposure to radiation, there is a need to determine whether a full-length

36-inch radiograph is necessary to evaluate the sagittal parameters of the

cervical spine, if a dedicated cervical spine film has already been obtained.

PURPOSE: To determine whether there is a correlation between sagittal

measures of the spine taken from a dedicated cervical spine radiograph

and those taken from a 36-inch spine radiograph.

STUDY DESIGN/SETTING: Cross sectional study from a single tertiary

spine practice.

Refer to onsite Annual Meeting presentations and postmeeting proceedings for po

reporting disclosures and FDA device/drug

PATIENT SAMPLE: Patients who had a cervical spine radiograph and

36-inch spine radiograph within four weeks of each other were identified

from the billing database.

OUTCOME MEASURES: C0-C2, C0-C7, C1-C2 and C2-C7 Sagittal

Cobb angles; T1 slope; Chin-brow-vertical angle (CBVA), C1-C7 sagittal

vertical axis (SVA), C2-C7 SVA, Center of Gravity-C7 sagittal vertical ax-

is (COG-C7 SVA).

METHODS: On separate occasions, de-identified radiographs were eval-

uated and the following radiographic measures were determined: C0-C2,

C0-C7, C1-C2 and C2-C7 Sagittal Cobb angles; T1 slope; CBVA, C1-

C7 SVA, C2-C7 SVA and COG-C7 SVA. Paired t-tests and correlation

analyses were performed between the corresponding paired radiographic

parameter as measured on the cervical spine radiograph and the 36-inch

radiograph. Correlation coefficients between 0.60 and 080 indicate a

marked degree of correlation; while coefficients between 0.80 and 1.00 in-

dicate robust correlations.

RESULTS: Radiographic measurements were collected on 40 patients.

There were 33 females and 7 males with a mean age of 48.9 6 14.5 years.

All correlations were statistically significant at p!0.001. All sagittal Cobb

measures showed a marked correlation. The C0-C2 sagittal Cobb had the

strongest correlation (r50.81) and the C2-C7 sagittal Cobb had the weak-

est (0.62). Among the sagittal balance parameters, the COG-C7 SVA had

the weakest correlation (r50.42) and the C1-C7 SVA (r50.64) and the C1-

C7 SVA (r50.65) had strong correlations. The T1 slope and the CBVA had

correlation coefficients of 0.74 and 0.91 respectively. Paired t-tests showed

that there was no statistically significant difference in the measures taken

from the cervical radiograph and 36-inch radiograph, except for the C0-C7

sagittal Cobb (p50.000) with a measurement difference of 7 degrees and

the T1 tilt (p50.000) with a measurement difference of 5 degrees.

CONCLUSIONS: Except for COG-C7 SVA, strongcorrelations between

most cervical spine parameters taken from a dedicated cervical spine ra-

diograph and those taken from a 36-inch radiograph. Most measures were

similar when evaluated from either film. A full-length 36-inch radiograph

may not be necessary to evaluate the cervical spine when a dedicated cer-

vical spine radiograph has already been obtained.

FDA DEVICE/DRUG STATUS: This abstract does not discuss or include

any applicable devices or drugs.

http://dx.doi.org/10.1016/j.spinee.2014.08.017

4. Does Intrawound Application of Vancomycin Influence Bone

Regeneration in Spinal Fusion?

Claudia Eder, MD1, Stefan Schenk, MD2, Jana Trifinopoulos1,

Sabrina Schildboeck1, Melanie Kienzl1, Michael Ogon, MD3;1Orthop€adisches Hospital Speising, Austria; 2Vienna, Austria;3Orthopaedisches Spital Speising Gmbh, Wien, Austria

BACKGROUND CONTEXT: Surgical site infection is a major complica-

tion of spinal deformity surgery. The application of lyophilized Vancomy-

cin into the wound prior to wound closure is reported to significantly

decrease infection rates. As concentrations applied can exceed the minimal

bacterial inhibitory concentration for more than a thousand fold, a poten-

tial inhibitory side effect on eukaryotic cells might impair bone healing

and increase the risk of non union.

PURPOSE: Aim of the presented study is to investigate the dose-dependant

effect of Vancomycin on human osteoblasts in vitro.

STUDY DESIGN/SETTING: controlled in vitro study; all experiments

were performed in triplicates and repeated on two different occasions.

PATIENT SAMPLE: primary osteoblast cultures from five patients were

generated.

OUTCOME MEASURES: cell migration, proliferation and viability as

well as morphological features were analyzed.

METHODS: Primary osteoblast cultures were generated from bone tissue

removed during deformity surgery in 5 patients. Bone samples were placed

in a tissue culture plate and incubated in Dulbecc�os Modified Eagl�es

ssible referenced figures and tables. Authors are responsible for accurately

status at time of abstract submission.