The Value of Multilevel Fusions for Adult Spinal Deformity: A Retrospective Analysis of Outcomes and Cost of Care

NASS 31st Annual Meeting Proceedings / The Spine Journal 16 (2016) S251–S337 recent studies. Increased rates of these complications have been reported with a 2-rod vs. multi-rod construct, or smaller rod diameter. In this regard, we sought to assess the prevalence of osteotomy site pseudarthrosis and failure after 3CO with primarily 2-rod constructs, using titanium 5.5 mm rods. PURPOSE: The purpose of this study is to evaluate pseudarthrosis rates and incidence of implant failure after three column osteotomy in adult spinal deformity patients. STUDY DESIGN/SETTING: Retrospective review of prospective database. PATIENT SAMPLE: One hundred and sixty-four patients, of whom 72% were female, who underwent three column osteotomy for adult spinal deformity with a mean age of 56±14 years were included in this study. OUTCOME MEASURES: Radiographic parameters including osteotomy site fusion grading, and rates of pseudarthrosis and implant failure, were calculated. Relevant perioperative complications and revision rates were evaluated. METHODS: Of 222 patients who underwent 3CO, 164 (73.9%) had minimum one-year radiographic and clinical follow up (41.9 months). Fusion grades were assigned to osteotomy sites based on published radiographic criteria. 3CO site failure was defined as radiographic osteotomy site pseudarthrosis, revision for pseudarthrosis at the osteotomy site, or rod fracture (RF) at the osteotomy site. RESULTS: Of the 164 patients, mean fusion grade at the osteotomy site was 1.3±0.5. Fourteen patients (8.5%) developed a pseudarthrosis after the 3CO procedure. Three of the 14 patients (1.8%) had a pseudarthrosis at the osteotomy site. Six patients overall (3.7%) demonstrated 3CO site failure: RF at the osteotomy site (3, 1.8%); revision for pseudarthrosis at the osteotomy site (3, 1.8%). The overall rate of RF was 3.7%. Titanium rods, 5.5 mm, were used in all patients; 2-rod construct: 86.6%, 3-rod construct: 8.5%, 4-rod construct: 4.9%. Offset connectors were used in 40% of patients. Main sources of bone graft were: local bone (100%), DBM (89.6%), iliac crest (17.7%) and BMP (11.6%). An interbody fusion cage at the osteotomy site was used in 66.5% of cases. No significant difference was seen in number of rods, number of offset connectors, use of BMP or interbody fusion at the 3CO site failure (p>.05). CONCLUSIONS: Our data demonstrate a 3.7% rate of 3CO site failure, of which 1.8% was due to pseudarthrosis, and 1.8% RF at the osteotomy site. While an association between smaller rod diameter, rod number and configuration and 3CO site failure has been reported, the low rate seen in this series may warrant further multi-center investigation. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.

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STUDY DESIGN/SETTING: Retrospective study of consecutive patients treated with multilevel spinal fusion for ASD at a single center by members of the orthopedic spine team. PATIENT SAMPLE: ASD patients who underwent primary multilevel fusions from the upper thoracic spine (T3/T4) and lower thoracic spine (T10/ T11) to pelvis met inclusion criteria. OUTCOME MEASURES: Outcome measures included direct costs, changes in patient reported health status (VAS/EQ5-d), intra- and perioperative complications, revision/readmission rates, and infection rates. METHODS: Institutional Review Board approval was obtained before conducting the study. The patient cohort was identified through review of the spine-center’s surgical ontologies. Patients were excluded if they had previous surgery in the same location, underwent surgery for tumor or infection, or had incomplete cost data. Demographic data, surgical data, and direct cost data in the categories of supplies, services, room and care, and pharmacy, were collected for each patient. Surgical details were confirmed through chart review. RESULTS: The cohort included 109 patients. Direct costs ranged from $26,936–$140,777 (mean=$78,899±$22,015). Cost variability was the highest in pharmaceutical expenses (20.35 fold) and lowest for time related operating room costs (3.55 fold). Implant costs were the largest contributor to the direct cost of care (46.7%) There was no correlation between outcomes achieved per direct cost dollar (r=0.003). Mean change in EQ-5D was 0.21 with 81% of patients experiencing a positive change in health status. Health status improved more dramatically in fusions to the lower thoracic (mean change in EQ-5D of 0.25) than to fusions to the upper thoracic (mean change in EQ-5D of 0.14). Intra- and perioperative complications were 36% and 40% respectively. 24% of patients required revision surgery. Mean time until revision surgery was 247 days. Those who had revision surgery had an average of 1.47 additional surgeries in addition to their index surgery. BMI was highly correlated with the need for revision surgery. Obese patients (BMI>30) had a 38% revision rate, while normal patients (18.5
http://dx.doi.org/10.1016/j.spinee.2016.07.455 http://dx.doi.org/10.1016/j.spinee.2016.07.456 P130. The Value of Multilevel Fusions for Adult Spinal Deformity: A Retrospective Analysis of Outcomes and Cost of Care Daniel Beckerman, BA1, Matt Callahan, MBA2, Linda Racine3, Sigurd H. Berven, MD1, Shane Burch, MD2, Vedat Deviren, MD2; 1UCSF, Department of Orthopedic Surgery, San Francisco, CA, USA; 2University of California San Francisco, San Francisco, CA, USA; 3Scoliosis Association of San Francisco, El Granada, CA, USA BACKGROUND CONTEXT: Medical expenditures for the diagnosis and treatment of spinal deformity are increasing more rapidly than other areas of health expenditures. Surgical management of spinal deformity is also characterized by significant variability in rates, costs and approaches to care. Such variability is clear evidence of the absence of an evidence-based approach to care. Areas of both high cost and high variability present potential targets for innovation, cost-saving and the promotion of consensus in clinical practice. PURPOSE: The purpose of this study is to analyze the cost components of surgery for adult deformity, and to report correlations between outcomes and costs of care in patients treated with multilevel fusion surgery for adult spinal deformity (ASD).

P131. Outcomes in Adult Deformity Surgery: What Happens to Those Patients Who are Lost to Follow-Up? Daniel Beckerman, BA1, Tamara Sharf1, Linda Racine2, Shane Burch, MD3, Sigurd H. Berven, MD1; 1UCSF, Department of Orthopedic Surgery, San Francisco, CA, USA; 2Scoliosis Association of San Francisco, El Granada, CA, USA; 3University of California San Francisco, San Francisco, CA, USA BACKGROUND CONTEXT: Measuring clinical outcomes after surgery for spinal disorders is important to guide an evidence-based approach to care. Loss of patients to follow-up is a significant limitation of many clinical outcome papers. There are several barriers that may prevent patients from following up after surgery including inconvenience, geographical distance, financial constraints, change in insurance coverage, or satisfaction with care. The purpose of this paper is to report the reasons that patients lost to followup did not follow-up, and the outcomes of care in these patients. PURPOSE: The purpose of this paper is to report the reasons that patients lost to follow-up did not follow-up, and the outcomes of care in these patients.

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