To identify preoperative factors that lead to cost-effectiveness at 2 years’ follow-up in the setting of surgical treatment for adult spinal deformity.
Retrospective analysis of a prospective, consecutive, multicenter database including 514 patients who underwent surgery for adult spinal deformity. The change in quality-adjusted life-years (QALY) was calculated from the 2-year change in Oswestry Disability Index (ODI). Medicare coding was used to determine the direct costs based on diagnosis-related group and Relative Value Unit reimbursement. Analysis was performed to determine which factors were associated with a cost/QALY less than $100,000, making the procedure cost-effective.
The average QALY change for all patients in this study was 0.15 and the average cost/QALY was $243,761.97. A total of 56 patients (10.4%) had a cost/QALY of less than $100,000 at 2-year follow-up. Those patients were mostly female (89%), with a mean age of 60 years and the following diagnoses: 18 (32.1%) adult idiopathic scoliosis, 12 (35.7%) adult de novo scoliosis, 87 (14.3%) sagittal imbalance, and 10 (17.9%) other scoliosis. The Health-Related Quality of Life ODI and Scoliosis Research Society (SRS) instruments were all associated with cost-effectiveness except SRS—Mental. Factors associated with cost-effectiveness were age greater than 55 years, adult de novo scoliosis, prior surgery, higher preoperative sagittal vertical axis, lower maximum Cobb angles, 8 or fewer fusion levels, lower blood loss, worse global alignment classification, and global sagittal malalignment. Combined anterior-posterior surgeries were negatively associated with cost-effectiveness. Preoperative ODI scores between 60 and 70 and SRS Pain and Activity subscores more than 4 minimally clinically important difference points below the normative values had the highest percentage of cost-effective patients.
The QALY change is 0.15 and the cost/QALY of adult deformity surgery is $243,761.97 at 2 years. Patients with higher preoperative morbidity are more likely to be cost-effective with a cost/QALY less than $100,000.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Price includes VAT for USA
Carter OD, Haynes SG. Prevalence rates for scoliosis in US adults: results from the first National Health and Nutrition Examination Survey. Int J Epidemiol 1987;16:537–44.
Francis RS. Scoliosis screening of 3,000 college-aged women: the Utah Study—phase 2. Phys Ther 1988;68:1513–6.
Glassman SD, Bridwell K, Dimar JR, et al. The impact of positive sagittal balance in adult spinal deformity. Spine (Phila Pa 1976) 2005;30:2024–9.
Grubb SA, Lipscomb HJ, Coonrad RW. Degenerative adult onset scoliosis. Spine (Phila Pa 1976) 1988;13:241–5.
Kostuik JP, Bentivoglio J. The incidence of low back pain in adult scoliosis. Acta Orthop Belg 1981;47:548–59.
Robin GC, Span Y, Steinberg R, et al. Scoliosis in the elderly: a follow-up study. Spine (Phila Pa 1976) 1982;7:355–9.
Schwab F, Dubey A, Pagala M, et al. Adult scoliosis: a health assessment analysis by SF-36. Spine (Phila Pa 1976) 2003;28:602–6.
Laupacis A, Feeny D, Detsky AS, Tugwell PX. How attractive does a new technology have to be to warrant adoption and utilization? Tentative guidelines for using clinical and economic evaluations. CMAJ 1992;146:473–81.
Rihn JA, Berven S, Allen T, et al. Defining value in spine care. Am J Med Qual. 2009;24:4S–14S.
Smith HE, Rihn JA, Brodke DS, et al. Spine care: evaluation of the efficacy and cost of emerging technology. Am J Med Qual 2009;24:25S–31S.
Kamerlink JR, Quirno M, Auerbach JD, et al. Hospital cost analysis of adolescent idiopathic scoliosis correction surgery in 125 consecutive cases. J Bone Joint Surg Am 2010;92:1097–104.
Barnett DB. Assessment of quality of life. Am J Cardiol 1991;67:41C–4C.
Grosse SD, Teutsch SM, Haddix AC. Lessons from cost-effectiveness research for United States public health policy. Annu Rev Public Health 2007;28:365–91.
Schwab F, Ungar B, Blondel B, et al. Scoliosis Research Society—Schwab adult spinal deformity classification: a validation study. Spine (Phila Pa 1976) 2012;37:1077–82.
Warren D, Hoelscher CM, Terran JS, et al. Adult spinal deformity: a two-year cost-utility analysis and 10-year thought experiment. Paper presented at: The American Academy of Orthopaedic Surgeons Annual meeting, February 9, 2012, San Francisco, CA.
Nichol MB, Sengupta N, Globe DR. Evaluating quality-adjusted life years: estimation of the health utility index (HUI2) from the SF-36. Med Decis Making 2001;21:105–12.
Carreon LY, Glassman SD, McDonough CM, et al. Predicting SF-6D utility scores from the Oswestry disability index and numeric rating scales for back and leg pain. Spine (Phila Pa 1976) 2009;34:2085–9.
Baldus C, Bridwell K, Harrast J, et al. The Scoliosis Research Society Health-Related Quality of Life (SRS-30) age-gender normative data: an analysis of 1346 adult subjects unaffected by scoliosis. Spine (Phila Pa 1976) 2011;36:1154–62.
Berven S DV, Demir-Deviren S, Hu S, Bradford D. Minimal clinically important difference in adult spinal deformity: how much change is significant? Paper presented at: International Meeting for Advanced Surgical Techniques, IMAST 2005; Banff, Canada.
Fairbank JC, Pynsent PB. The Oswestry Disability Index. Spine (Phila Pa 1976) 2000;25:2940–52; discussion 52.
Tosteson AN, Tosteson TD, Lurie JD, et al. Comparative effectiveness evidence from the spine patient outcomes research trial: surgical versus nonoperative care for spinal stenosis, degenerative spondylolisthesis, and intervertebral disc herniation. Spine (Phila Pa 1976) 2011;36:2061–8.
Glassman SD, Polly DW, Dimar JR, Carreon LY. The cost effectiveness of single-level instrumented posterolateral lumbar fusion at 5 years after surgery. Spine (Phila Pa 1976) 2012;37:769–74.
Bridwell KH, Baldus C, Berven S, et al. Changes in radiographic and clinical outcomes with primary treatment adult spinal deformity surgeries from two years to three- to five-years follow-up. Spine (Phila Pa 1976) 2010;35:1849–54.
Bridwell KH, Glassman S, Horton W., et al. Does treatment (nonoperative and operative) improve the two-year quality of life in patients with adult symptomatic lumbar scoliosis: a prospective multicenter evidence-based medicine study. Spine (Phila Pa 1976) 2009;34:2171–8.
Smith JS, Shaffrey CI, Berven S, et al. Operative versus nonoperative treatment of leg pain in adults with scoliosis: a retrospective review of a prospective multicenter database with two-year follow-up. Spine (Phila Pa 1976) 2009;34:1693–8.
Kim YJ, Bridwell KH, Lenke LG, et al. Results of lumbar pedicle subtraction osteotomies for fixed sagittal imbalance: a minimum 5-year follow-up study. Spine (Phila Pa 1976) 2007;32:2189–97.
Cho SK, Bridwell KH, Lenke LG, et al. Comparative analysis of clinical outcome and complications in primary versus revision adult scoliosis surgery. Spine (Phila Pa 1976) 2012;37:393–401.
Cho SK, Bridwell KH, Lenke LG, et al. Major complications in revision adult deformity surgery: risk factors and clinical outcomes with two- to seven-year follow-up. Spine (Phila Pa 1976) 2012;37:489–500.
Daubs MD, Lenke LG, Cheh G, et al. Adult spinal deformity surgery: complications and outcomes in patients over age 60. Spine (Phila Pa 1976) 2007;32:2238–44.
Gold MR, Stevenson D, Flyback DG. HALYS and QALYS and DALYS, oh my: similarities and differences in summary measures of population health. Annu Rev Public Health 2002;23:115–34.
Crandall D, Schmidt K, Revella J, et al. Can patients reliably work long-term after fusion for adult deformity? Paper presented at: 46th annual SRS meeting; September 17, 2011, Louisville, KY
Glassman SD, Carreon LY, Shaffrey CI, et al. The costs and benefits of nonoperative management for adult scoliosis. Spine (Phila Pa 1976) 2010;35:578–82.
Hatten AL, Gatchel RJ, Polatin PB, Stowell AW. A cost-utility analysis of chronic spinal pain treatment outcomes: converting SF-36 data into quality-adjusted life years. Clin J Pain 2006;22:700–11.
Ashenfelter O. Measuring the value of a statistical life: problems and prospects. Economic Journal 2006;116:C10–23.
Bobinac A, Van Exel NJ, Rutten FF, Brouwer WB. Willingness to pay for a quality-adjusted life-year: the individual perspective. Value in Health 2010;13:1046–55.
Author disclosures: CRF (none); JT (none); BL (grants from Setting Scoliosis Straight Foundation, John and Marcella Fox Fund, OREF, Depuy Spine; personal fees from Depuy Spine, Paradigm Spine, Spine Search, K2M; grants from AO Spine, outside the submitted work); BM (none); DW (none); SG (other from Norton Healthcare, Medtronic Sofamor Danek, Nuvasive, SRS, outside the submitted work; patent US Application No. 12/013,838 with royalties paid); KB (none); FS (grants from MSD, during the conduct of the study; personal fees from MSD, K2M, Nemaris, Inc, MSD, DePuy, K2M, MSD; grants from DePuy, MSD, AO, outside the submitted work; patent MSD with royalties paid, a patent K2M pending, patent Nemaris, Inc, pending.); VL (grants from MSD, during the conduct of the study; personal fees from Nemaris, Inc, MSD, DePuy, K2M; grants from DePuy, ISSG, SRS, NIH, outside the submitted work).
Portions of this article were presented in abstract/podium form at the Scoliosis Research Society annual meeting, September 5e8, 2012, Chicago, IL.
About this article
Cite this article
Fischer, C.R., Terran, J., Lonner, B. et al. Factors Predicting Cost-effectiveness of Adult Spinal Deformity Surgery at 2 Years. Spine Deform 2, 415–422 (2014). https://doi.org/10.1016/j.jspd.2014.04.011
- Adult spinal deformity
- Spinal fusion