Proceedings of the NASS 25th Annual Meeting / The Spine Journal 10 (2010) 1S–149S 1
Raderrick Davey, MD, FRCSC , Marcel Dvorak, MD, FRCSC , Joel Finkelstein, MD, FRCSC6, Charles Fisher, MD, FRCSC5, Rajiv Gandhi, MD, FRCSC1, Stephen Lewis, MD, FRCSC1, Nizar Mahomed, MD, FRCSC1, William Oxner, MD, FRCSC4, Albert Yee, MD, FRCSC6; 1University Health Network, Toronto Western Hospital, University of Toronto, Toronto, ON, Canada; 2 Ottawa Hospital, Ottawa, ON, Canada; 3Atlantic Health Sciences Corporation, St John’s, NB, Canada; 4QEII Health Sciences Center, Halifax, NS, Canada; 5Vancouver Coastal Health Research Institute, Vancouver, BC, Canada; 6Sunnybrook Health Sciences Center, Toronto, ON, Canada BACKGROUND CONTEXT: Several tightly controlled studies have shown that surgical intervention for lumbar spinal stenosis (LSS) leads to improved quality of life over nonoperative treatment (Weinstein 2008). In addition the results of smaller single center studies have shown that surgical intervention for LSS yielded comparable results to both hip and knee arthroplasty (THA/TKA). Whether these results are generalizable to routine clinical practice, particularly on a national perspective is unknown. PURPOSE: The primary purpose of this study is to nationally compare the relative improvement in quality of life after surgical intervention for focal lumbar spinal stenosis (FLSS) compared to hip and knee osteoarthritis. STUDY DESIGN/SETTING: A Canadian multicenter retrospective cohort study was performed. PATIENT SAMPLE: Patients who had primary 1–2 level spinal decompression with or without instrumented fusion for FLSS and THA/TKA for primary osteoarthritis. OUTCOME MEASURES: Change in preoperative to postoperative SF-36 - Physical Component Summary (PCS) score. METHODS: A cohort of primary 1–2 level spinal decompression (n5389) with (n5224/389) or without instrumented fusion for spinal stenosis (n5179 with degenerative spondylolisthesis) with a minimum of 2 year follow-up were compared to a cohort of primary total hip (n5178) and knee (n5235) arthroplasty for osteoarthritis (n5413) using multivariable regression modeling. RESULTS: The mean age (yrs) and percent females for the spine, hip and knee groups were 63.3/58.5, 66.0/46.9, and 65.8/64.3 respectively. All three groups experienced significant improvement of baseline PCS (p!0.001). (Table 1) Unadjusted change in PCS was superior for hips, however, there was no difference in knee compared to spine outcomes. Univariate predictors (p!0.01) of greater PCS change included younger age, higher baseline MCS, lower baseline PCS, fusion, spondylolisthesis and geographic site. Using Scheffe’s test for multiple comparisons, no one specific site was better than the other. The difference between sites was not clinically significant. Multivariable regression analysis revealed that hip replacement resulted in superior change in PCS while spines where equivalent to knees. Similar finding was noted regarding the number of patients reaching minimal clinical important difference (MCID) and substantial clinical benefit (SCB). The mean improvement in SF-36 sub-component scores were comparable to the results of the SPORT studies. CONCLUSIONS: Significant improvement in HRQOL following surgical treatment of FLSS is consistently achieved nationally. Furthermore, this data is comparable to the SPORT trails, and thus this study supports generalizablility of the SPORT data. This finding also suggests that a significant selection bias effect in the FLSS results is less likely. The overall change in PCS for FLSS is equivalent to knee arthroplasty, but inferior to hip replacement. These results support the need for increased knowledge transfer and advocacy regarding the management of this growing spine demographic. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
210. Degenerative Spondylolisthesis Score (DS Score) as a Significant Predictor of the Development of DS in Female Cohort Kiyoshi Aono, MD, Tetsuya Kobayashi, MD, Yuji Atsuta, MD, Takeo Matsuno, MD; Asahikawa Medical College, Asahikawa, Japan BACKGROUND CONTEXT: Degenerative lumbar spondylolisthesis (DS) is among the most frequent spinal deformity in the ageing spine, however, the etiological aspects of DS have not been welldocumented. PURPOSE: This study was designed to identify radiographic predictors of DS in a prospective study of community-based healthy female volunteers. STUDY DESIGN/SETTING: Prospective cohort study. PATIENT SAMPLE: This study was a component of the ASAP study since 1983, an on-going prospective observational study including over 500 healthy volunteers recruited from population register, and final total of 142 community-based female volunteers, aged 40–75 years with no DS at baseline x-ray, were followed for 8–15 years. OUTCOME MEASURES: Radiographic measurements of sagittal spinopelvic alignment. METHODS: Standardized serial entire spine radiographs were used for measuring thoracic kyphosis, lumbar lordosis (LL), pelvic incidence (PI), sagittal spinal balance, disc height ratio, vertebral inclination angle (VA), facet sagittalization (FS), and the magnitude of spondylolisthesis with more than 5% slip defined as newly-developed DS. RESULTS: Subjects’ baseline age was 54.7 years, and during mean follow-up period of 12.1 years, 18 subjects (12.7%) developed DS. In multivariate analysis, PI, VA, and FS were confirmed to be independent predictors of DS, and significant differences were demonstrated in baseline LL (DS 40.5 vs. non-DS 32.7 , P50.0151), PI (DS 62.4 vs. non-DS 54.7 , P50.0056), VA (L4-VA DS 12.0 vs. non-DS 5.3 , P50.0135; L5-VA DS 23.2 vs. non-DS 16.4 , P50.0167), and FS (DS 33.3% vs. non-DS 4.8%, P!0.0001). Using each mean value of measured variable in DS subjects, we introduced DS score which evaluated the number of following risk factors; 1) LLO41 , 2) PIO63 , 3) L4-VAO12 , 4) L5VAO24 , and 5) positive FS. DS score showed significant linear correlation with the incidence of DS, and DS score of 4 or more exhibited 80% incidence of DS (P50.0021). CONCLUSIONS: The value of PI determines the capacity of pelvic retroversion, and greater PI has been suggested as a risk of DS. Our study is the first to confirm that greater PI was an independent predictor of DS in a prospective manner, and introduced DS score, using the value of lumbar lordosis, vertebral inclination, facet shape, and PI, predicted the development of DS among susceptible female subjects. Further studies are necessary to better understand the etiology of this frequent spinal deformity in the aging spine. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. doi: 10.1016/j.spinee.2010.07.258
211. Preoperative Health-Related Quality of Life Scores as Predictor of Clinical Outcomes after Degenerative Lumbar Surgery Sabarul A. Mokhtar, MD, William R. Sears, FRACS; The Australian School of Advanced Medicine, Sydney, Australia BACKGROUND CONTEXT: With an aging population, degenerative lumbar spinal disorders are becoming a significant health care concern. Some patients who undergo surgery will suffer unfavorable outcomes. Numerous studies have sought to identify predictors of outcome, in an attempt to distinguish patients who are more likely to benefit from surgery. Measures of health-related quality-of-life (HRQL) are increasingly used in clinical studies to evaluate treatment effectiveness. However, the study of their use as a predictive tool has been limited.
All referenced figures and tables will be available at the Annual Meeting and will be included with the post-meeting online content.