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

Abstract

Evaluate costs and functional utility of post-discharge rehabilitation after surgery for adult spinal deformity (ASD). Retrospective analysis of ASD patients who underwent operation at a single center and discharged to one rehabilitation facility. Operative details and costs were obtained for index inpatient encounter. Rehabilitation data included: direct costs, length of stay, and patient function, as assessed by Functional Independence Measure (FIM) instrument. Of 937 operations, 391 (41.7%) were discharged to rehabilitation. Ninety-patients (9.6%; 95 care episodes; average age 70.5±10.6years) were discharged to rehabilitation. Inpatient length of stay was 8.2±2.6days. Operative details: posterior levels fused 13.6±3.6, PCOs/patient 7±3.7, forty-two 3-column osteotomies, and 11 inter-body fusions. Direct costs were $90,738±$24,166 for index hospitalizations and $38,808±$14,752 for rehabilitation. Patients spent 11.7±4.0days in rehabilitation. Direct cost per day in hospital ($11,758 ± $3390) was significantly greater than rehabilitation ($3338 ± $2131) (p < 0.05). Significant improvements in function while in rehabilitation were observed (admit FIM: 66±14 vs. discharge FIM: 94±14). Charlson Comorbidity Index was the only independent predictor of rehabilitation direct costs. Conclusion Post-discharge inpatient rehabilitation following operations for ASD is associated with a direct cost of $38,808 per case. While rehabilitation resulted in significant functional improvements, it came at significant economic expense ($3.7 million) that accounted for 30% of costs for 95 episodes of care. For 100 operatively treated patients (assuming 41% discharge rate to rehab), rehabilitation results in an additional price premium of $1,674,872.