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

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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; 2 Chicago, IL, USA; 3New York, NY, USA BACKGROUND CONTEXT: It has been suggested that certain radiographic features (i.e. magnitude of slip, disk space narrowing, and intervertebral 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 review, 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 index (SBI), and low back pain bothersomeness scale METHODS: Using the SPORT DS cohorts, we analyzed the data according 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 between the groups. Overall, surgery patients improved more than patients treated non-operatively. At one year, outcomes were similar in surgery patients 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-operatively. 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; 3 Boston, MA, USA; 4Hughston Clinic, PC, Columbus, GA, USA; 5 Louisville, KY, USA BACKGROUND CONTEXT: Most of the literature regarding lumbar fusion 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 conclusively 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 approved, FDA regulated, randomized, nonblinded IDE trial of rhBMP-2 matrix 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 posterolateral 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 improvement in back pain NRS scores at all time intervals with the difference 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 intervals. 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 comparison to literature standards and to a control population of younger patients.

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

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FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.

FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.

doi:10.1016/j.spinee.2008.06.006

doi:10.1016/j.spinee.2008.06.007

6. Outcomes Based on a Low Back Pain Classification System Greg McIntosh, MSC1, Hamilton Hall, MD2, Christina Boyle, BSC3; 1 Oakville, Ontario, Canada; 2Markdale, Ontario, Canada; 3Toronto, Ontario, Canada

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; 1 Dartmouth College, Lebanon, NH, USA; 2Lebanon, NH, USA; 3Rothman Institute, Philadelphia, PA, USA; 4Washington University in St. Louis, St. Louis, MO, USA

BACKGROUND CONTEXT: One goal of LBP assessment is to direct clinicians to specific sub-groups that benefit from particular treatment approaches. 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 conservative care setting between patients assessed and treated based on a diagnostic 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 rehabilitation 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 assessment or treatment. The Classification Group (n51356) consisted of patients 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) subjective global pain rating, 2) change in reported medication usage from assessment 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 possible 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 orthopaedic surgeons. All clinics involved in this study are primary access, conservative 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 variable did not follow a normal distribution. Median values (32 days, interquartile range59.5, 121.5 days) suggest a more subacute sample. Treatment based on this classification system resulted in more pain reduction (p!0.001), higher functional improvement (p!0.001), less medication 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.

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-operative 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 characteristics 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 gastrointestinal (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, Oswestry 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-operatively improved less than those treated surgically, and there were no significant 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