Which spine surgeries belong in the ambulatory surgical center?

Neurosurg Focus 60(4):E2, 2026

This study uses time-driven activity-based costing (TDABC) to quantify true costs of common cervical and lumbar spine procedures performed in an outpatient hospital setting and compares these costs to Medicare ambulatory surgical center (ASC) reimbursement. Findings show microdiscectomy, lumbar laminectomy/decompression, and ACDF most often fall below Medicare ASC reimbursement, while endoscopic discectomy and posterior lumbar fusion frequently exceed reimbursement.

The analysis identifies supplies and personnel as primary cost drivers, highlights heterogeneity in Medicare ASC facility fees that do not reflect procedural complexity or number of levels, and argues that reimbursement reform is needed to expand the range of spine procedures economically feasible in ASCs.

Objective Identify spine procedures that are economically suitable to move from an outpatient hospital setting to an ambulatory surgical center (ASC) by comparing true costs (via TDABC) with Medicare ASC reimbursement.

Methods Retrospective cohort (2020–2024) of outpatient hospital spine cases with length of stay ≤ 1 day; procedures: cervical disc arthroplasty, ACDF, lumbar laminectomy/decompression, microdiscectomy, endoscopic discectomy, and posterior lumbar fusion; primary outcomes were total costs and proportion of cases with cost below Medicare reimbursement; regression adjusted for age, sex, BMI, and number of levels.

Costing approach (TDABC) Episode mapped across preop, intraop (wheels-in to wheels-out), and recovery phases; costs included supplies (consumables, implants, meds), personnel time (per-minute rates by role), and overhead.

Key cervical finding ACDF was more often below corresponding ASC reimbursement than cervical disc arthroplasty (71.8% vs 40.0%); adjusted odds favored ACDF (OR 5.3, 95% CI 3.0–9.4).

Key lumbar cost levels Mean lumbar episode cost was $4,640 ± $6,475; posterior lumbar fusion had the highest mean cost ($25,042 ± $15,645) and microdiscectomy the lowest ($3,233 ± $2,142).

Key lumbar viability finding Microdiscectomy (95.3%) and laminectomy/decompression (94.5%) most often cost less than reimbursement; endoscopic discectomy (31.0%) and posterior lumbar fusion (30.0%) were least often below reimbursement; adjusted odds were higher for laminectomy/decompression (OR 6.0) and microdiscectomy (OR 4.7), and far lower for endoscopic discectomy (OR 0.01) and fusion (OR 0.02).

Conclusions (procedures best suited for ASC under current payments) Microdiscectomy, lumbar laminectomy/decompression, and ACDF appear most economically suitable for transition from hospital outpatient to ASC in existing payment structures.

Reimbursement implication Broader feasibility in ASCs likely requires reimbursement reform, given mismatches between procedural complexity/resource use and Medicare ASC payment patterns.