1532. Costs and utility of post-discharge acute inpatient rehabilitation following adult spinal deformity surgery

Award: Third Place Spine Eposter Award

Authors: Alexander Theologis; Darryl Lau; Adelyn Tsu; Cecilia Dalle-Ore; Vedat Deviren; Christopher Ames (San Francisco, CA)

Introduction: As the United States’ healthcare system transitions to a value-based approach, defining costs for entire episodes of care is fundamental to determining value. This study aims to evaluate the costs and functional utility of post-discharge acute inpatient rehabilitation after surgery for adult spinal deformity (ASD). Methods: Retrospective analysis of ASD who underwent operation (³7 levels fused) who were discharged post-operatively to acute rehabilitation. Patient demographics, operative details, and costs were obtained for the index operation’s inpatient encounter. Data for acute rehabilitation included: direct costs, length of stay, and patient function, as assessed by the Functional Independence Measure (FIM) instrument. p < 0.05 set statistical significance. Results: Ninety-patients (95 episodes of care; average age 70.5 ± 10.6 years; male 31, female 59) were included for analysis. After operations, average inpatient length of stay was 8.2±2.6 days. Operative details included: posterior levels fused 13.6±3.6, posterior column osteotomies (per patient) 7±3.7, forty-two 3-column osteotomies (PSO-35, VCR-7), and 11 interbody fusions (ALIF-2, TLIF-9). Average direct costs were $90,738±$24,166 for index inpatient stays and $38,808±$14,752 for post-discharge acute rehabilitation. Patients spent an average of 11.7±4.0 days in acute rehabilitation post-discharge. Average direct cost per day in rehabilitation was $5,162±$2,344. Significant improvements in function, as assessed by FIM scores, were observed [admit: 66 ± 14 v. discharge: 94 ± 14; % improvement: 29±14]. Conclusion: Post-discharge inpatient acute rehabilitation following operations for adult spinal deformity is associated with an average direct cost of $38,808 per case. While rehabilitation resulted in significant functional improvements, it came at a very significant economic expense amounting to $3.7 million, which accounted for 30% of the costs for 95 episodes of care.