2S Proceedings of the NASS 23rd Annual Meeting / The Spine Journal 8 (2008) 1S–191S

pain groups. Similar non-operative outcomes were observed for the three

pain location groups at 2 years in both the DS and SpS cohorts.

CONCLUSIONS: Overall, surgery resulted in better outcomes compared

to non-operative treatment for all patients regardless of pain location.

However, predominant leg pain patients improved more with surgery than

predominant back pain patients.

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

any applicable devices or drugs.

doi:10.1016/j.spinee.2008.06.003

3. Radiographic Predictors of Clinical Outcomes Following

Operative or Non-Operative Treatment of Degenerative

Spondylolisthesis

Adam Pearson, MD1, Jon Lurie, MD1, Emily Blood, MS1, John Frymoyer,

MD1, Heike Braeutigam, MD1, Howard An, MD2, Federico Girardi, MD3,

James Weinstein, DO1; 1Dartmouth College, Lebanon, NH, USA;2Chicago, IL, USA; 3New York, NY, USA

BACKGROUND CONTEXT: It has been suggested that certain radio-

graphic features (i.e. magnitude of slip, disk space narrowing, and interver-

tebral hypermobility) are related to outcomes in degenerative

spondylolisthesis (DS).

PURPOSE: This study evaluated whether baseline radiographic findings

predicted outcomes in patients with degenerative spondylolisthesis (DS).

STUDY DESIGN/ SETTING: The Spine Patient Outcomes Research

Trial (SPORT) included randomized and observational cohorts, with 13

participating institutions in 11 states.

PATIENT SAMPLE: 222 DS patients with radiographs available for re-

view, representing a subset of the total cohort of 591 DS patients

OUTCOME MEASURES: SF-36 bodily pain (BP) and physical function

(PF) scales, Oswestry disability index (ODI), stenosis bothersomeness in-

dex (SBI), and low back pain bothersomeness scale

METHODS: Using the SPORT DS cohorts, we analyzed the data accord-

ing to treatment received. The Meyerding listhesis grade was determined

on the neutral radiograph (n5222). A patient was classified as having

low disk height if the disk height was less than 5 mm. Flexion-extension

radiographs (n5185) were evaluated for mobility. Those with greater than

10� rotation or 4 mm translation were considered Hypermobile. Changes in

outcome measures were compared between listhesis (Grade 1 vs. Grade 2),

disk height (Low vs. Normal) and mobility (Stable vs. Hypermobile)

groups using longitudinal regression models adjusted for potential

confounders.

RESULTS: Overall, 86% had a Grade 1 listhesis, 78% had Normal disk

height, and 73% were Stable. Baseline symptom severity was similar be-

tween the groups. Overall, surgery patients improved more than patients

treated non-operatively. At one year, outcomes were similar in surgery pa-

tients across listhesis, disk height, and mobility groups (ODI: Grade 1

�23.7 vs. Grade 2 �23.3, p50.90; Normal disk height �23.5 vs. Low disk

height �21.9, p50.66; Stable �21.6 vs. Hypermobile �25.2, p50.30).

Among those treated non-operatively, Grade 1 patients improved more

than Grade 2 patients (BP +13.1 vs. �4.9, p50.019; ODI �8.0 vs. +4.8,

p50.010 at 1 year), and Hypermobile patients improved more than Stable

patients (ODI �15.2 vs �6.6, p50.041; SBI �7.8 vs �2.7, p50.002 at 1

year).

CONCLUSIONS: Regardless of listhesis grade, disk height or mobility,

patients who had surgery improved more than those treated non-opera-

tively. Surgical treatment effects were greater for Grade 2 patients and

for Stable patients. These differences were due, in part, to differences in

non-operative outcomes, which were better in patients classified as Grade

1 or Hypermobile.

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

any applicable devices or drugs.

doi:10.1016/j.spinee.2008.06.004

4. This paper will be presented during the TSJ Outstanding Paper

Awards presentations Thursday morning, October 16, 2008.

5. Outcome of Lumbar Fusion in Patients Over 65 Years Old

Steven Glassman, MD1, David Polly, Jr., MD2, Christopher Bono, MD3,

Kenneth Burkus, MD4, John Dimar, II, MD5; 1Leatherman Spine Center,

Louisville, KY, USA; 2University of Minnesota, Minneapolis, MN, USA;3Boston, MA, USA; 4Hughston Clinic, PC, Columbus, GA, USA;5Louisville, KY, USA

BACKGROUND CONTEXT: Most of the literature regarding lumbar fu-

sion in older patients has focused on the rate of complications. In 2006,

a CMS advisory panel meeting assessing evidence for spinal fusion surgery

in the Medicare population indicated a need for ‘‘better evidence to con-

clusively demonstrate improvement in health outcomes’’. Additionally,

the panel noted that the majority of evidence was in younger patients

and that it was unclear whether this data could be applied to the Medicare

population.

PURPOSE: The purpose of this study is to compare clinical outcomes for

lumbar fusion in older versus younger patients, within a clearly defined

study population.

STUDY DESIGN/ SETTING: Patients were treated as part of an IRB ap-

proved, FDA regulated, randomized, nonblinded IDE trial of rhBMP-2 ma-

trix for posterolateral lumbar spine fusion. The patients were those

randomized to the control arm (ICBG) of the IDE trial. Inclusion criteria

for this study were single level lumbar DDD in patients over 18 yrs of

age with no greater than Grade I spondylolisthesis.

PATIENT SAMPLE: 224 patients who underwent single-level posterolat-

eral lumbar fusion with ICBG.

OUTCOME MEASURES: ODI, SF-36, Numeric Rating Scales for Back

Pain and Leg Pain, and radiographic fusion.

METHODS: Outcomes were compared for 50 patients over 65 yrs of

age (mean 70.5 yrs) and 174 patients under 65 yrs of age (mean 47.0

yrs). Change in outcome measures were evaluated based upon both net

mean change and the percentage of patients reaching an MCID threshold.

Published MCID thresholds of 5.42 pts for SF-36 PCS and 10 pts for

ODI were utilized. Fusion was assessed by plain radiographs and CT

scans.

RESULTS: Statistically significant improvements from baseline were

noted in all of the HRQOL measures at the six month, one year and

two yearr post-op intervals. Mean improvements in ODI at two years

post-op were 28.5 in older patients and 24.5 in younger patients. Older

patients performed better at all time intervals, though only the six month

difference between groups was significant (p50.041), after adjusting for

preoperative ODI score. For the SF-36 PCS, mean improvement from

pre-op baseline was 14.2 in the over 65 group and 11.7 in the under

65 group at two years. Older patients also demonstrated a greater im-

provement in back pain NRS scores at all time intervals with the differ-

ence at six months being statistically significant and the difference at two

years post-op trending towards significance (8.8 vs. 7.7, p50.077). Leg

pain NRS scores were also better in older patients at all time intervals,

with the difference at two years post-op being statistically significant

(10.4 pts vs. 6.4 pts, p50.002). Percentage of patients reaching MCID

was also higher in the older group than the younger group at all time in-

tervals. At two years after surgery, a decrease in ODI score of 10 pts or

greater was achieved in 85.0% of older patients and 72.7% of younger

patients. Improvement of 5.42 pts or more in SF-36 PCS was observed

in 75.0% of older patients and 63.6% of younger patients. Successful

fusion was seen in 94.7% of patients over 65 years old and 87.7% of

patients under 65 years old.

CONCLUSIONS: This study demonstrates substantial benefit for

a Medicare age population treated by single-level lumbar decompression

and instrumented fusion. This improvement is evident both in compar-

ison to literature standards and to a control population of younger

patients.

3SProceedings of the NASS 23rd Annual Meeting / The Spine Journal 8 (2008) 1S–191S

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

any applicable devices or drugs.

doi:10.1016/j.spinee.2008.06.006

6. Outcomes Based on a Low Back Pain Classification System

Greg McIntosh, MSC1, Hamilton Hall, MD2, Christina Boyle, BSC3;1Oakville, Ontario, Canada; 2Markdale, Ontario, Canada; 3Toronto,

Ontario, Canada

BACKGROUND CONTEXT: One goal of LBP assessment is to direct

clinicians to specific sub-groups that benefit from particular treatment ap-

proaches. The term ’non-specific’ LBP does not direct treatment or instil

confidence in patients.

PURPOSE: The purpose of this study was to compare outcomes in a con-

servative care setting between patients assessed and treated based on a di-

agnostic system of LBP classification and patients managed without

a classification system.

STUDY DESIGN/ SETTING: This prospective double-cohort study

investigated mechanical LBP cases who started conservative care rehabil-

itation at 15 clinics across Canada between February 2006 and August

2007.

PATIENT SAMPLE: The two cohorts were: a Comparison Group

(n5754) and a Classification Group (n51469). All patients in both groups

had mechanical LBP. The Comparison Group contained those attending

treatment at 8 clinics that did not use a classification based system of as-

sessment or treatment. The Classification Group (n51356) consisted of pa-

tients attending 7 clinics specifically trained to use a LBP classification

system that emphasizes mechanical assessment, pattern of pain recognition

and appropriate treatment direction.

OUTCOME MEASURES: Primary outcomes assessed were: 1) subjec-

tive global pain rating, 2) change in reported medication usage from as-

sessment to discharge, 3) change in Visual Analogue Scale (VAS) pain

rating from assessment to discharge, 4) change in perceived function from

assessment to discharge, based on score change from a modified version of

the Low Back Outcome Score (LBOS) and 5) total number of treatment

days.

METHODS: The classification system is purposely as inclusive as possi-

ble to include more than those who may get labelled with NSLBP; thus,

very little study exclusion criteria were necessary. Those over 65 years

of age and those with neurological, reflex or strength deficits were included

because there are specific categories for those where age or signs of nerve

root compromise contribute to their condition. Only minors, those with

previous spine surgery and those with suspected systemic disease or cases

resulting from trauma sufficient to produce severe bony injury or major

neurological sequelae were excluded. Patients were either self-referred

to the clinics or referred via general practice, family physicians or ortho-

paedic surgeons. All clinics involved in this study are primary access, con-

servative care, rehabilitation facilities.

RESULTS: For both Comparison and Classification Groups, the mean

age was 44.7 years (SD513.3, range518–89,), with 55.1% males. The

mean lagtime from symptom onset to treatment was 110.7 days

(SD5201.5), indicating a somewhat chronic sample; however, this vari-

able did not follow a normal distribution. Median values (32 days, inter-

quartile range59.5, 121.5 days) suggest a more subacute sample.

Treatment based on this classification system resulted in more pain reduc-

tion (p!0.001), higher functional improvement (p!0.001), less medica-

tion use (p!0.001) and fewer treatment days (p!0.001), compared to

a generic approach.

CONCLUSIONS: Outcome differences between the five classified

groups suggest that LBP is heterogeneous, and recognizable by clinical

patterns of patient characteristics. The results support the effectiveness

of a classification system that matches treatment to patient presentation

and pattern of pain. Classification-based treatment had a positive impact

on outcomes.

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

any applicable devices or drugs.

doi:10.1016/j.spinee.2008.06.007

7. Spinal Stenosis vs. Degenerative Spondylolisthesis: Comparison of

Baseline Characteristics and Outcomes

Adam Pearson, MD1, Emily Blood, MS2, Jon Lurie, MD1, Tor Tosteson,

PhD1, Alan Hillibrand, MD3, Keith Bridwell, MD4, James Weinstein, DO2;1Dartmouth College, Lebanon, NH, USA; 2Lebanon, NH, USA; 3Rothman

Institute, Philadelphia, PA, USA; 4Washington University in St. Louis, St.

Louis, MO, USA

BACKGROUND CONTEXT: Spinal stenosis (SpS) and degenerative

spondylolisthesis (DS) patients are often combined in clinical studies. This

study contrasts these two distinct cohorts from the Spine Patient Outcomes

Research Trial (SPORT).

PURPOSE: To compare baseline characteristics and surgical and non-op-

erative outcomes between SpS and DS patients.

STUDY DESIGN/ SETTING: The Spine Patient Outcomes Research

Trial (SPORT) included randomized and observational cohorts, with 13

participating institutions in 11 states.

PATIENT SAMPLE: 615 SpS and 591 DS patients.

OUTCOME MEASURES: SF-36 Bodily Pain and Physical Function

scores, Oswestry Disability Index , Sciatica Bothersomeness Index, and

Back Pain Bothersomeness.

METHODS: The SPORT SpS cohort included 634 patients (394

underwent surgery within two years), and the DS cohort included 601

patients (369 underwent surgery within two years). Baseline characteris-

tics were compared between the two groups. Changes from baseline for

surgical and non-operative outcomes were estimated using longitudinal

regression models including baseline covariates to control for

confounders.

RESULTS: The SpS patients included a higher proportion of males

(61% vs. 31%, p!0.001); were younger (64.6 years vs. 66.1 years,

p50.021); were less likely to report depression (11% vs. 16%,

p50.009); more likely to report heart (26% vs. 20%, p50.021) or gastro-

intestinal (14% vs. 7%, p!0.001) problems; and were more likely to

have stenosis at multiple levels (61% vs. 35%, p!0.001) compared to

the DS patients. There were no significant baseline differences on any

of the main outcome measures between the SpS and DS patients. SpS

patients undergoing surgery were less likely to be fused than DS patients

(11% vs 95%, p!0.001). SpS patients improved less with surgery than

DS patients on SF-36 physical function (+25.1 vs. +30.5, p50.002 at

1 yr; +25.9 vs. +31.2, p50.001 at 2 yrs) and bodily pain (+27.2 vs.

+32.5, p50.002 at 1 yr; +21.2 vs. +28.4, p!0.001 at 2 yrs) scores, Os-

westry Disability Index (�20.8 vs. �26.1, p!0.001 at 1 yr; �20.1 vs.

�24.8, p!0.001 at 2 yrs), and Sciatica Bothersomeness Index (�8.4

vs. �9.4, p50.05 at 1 yr; �7.9 vs. �8.9, p50.031 at 2 yrs). Back Pain

Bothersomeness improved less in SpS patients at 1 yr (�2.0 vs. �2.4,

p50.012), though the difference was no longer significant at 2 yrs

(�2.0 vs. �2–2, p50.21). In both cohorts, patients treated non-opera-

tively improved less than those treated surgically, and there were no sig-

nificant differences in non-operative outcomes between the two cohorts at

one or two years.

CONCLUSIONS: Overall, SpS and DS patients had similar baseline

characteristics. However, SpS patients improved less with surgery than

DS patients. These differences in surgical outcomes may be related to

different underlying disease processes, different operative treatments or

both. Future studies should not combine these heterogeneous patient

populations.

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

any applicable devices or drugs.

doi:10.1016/j.spinee.2008.06.008