The Cost Effectiveness of Anterior versus Posterior and Transforaminal Lumbar Interbody Fusion for Degenerative Spine Disease: A Markov Model Based Evaluation

Introduction: Approaches used to treat degenerative spine disease include anterior lumbar interbody fusion (ALIF) and posterior or transformational fusion (PLIF/TLIF). However, there is no consensus regarding which procedure is superior as both surgeries share similar clinical outcomes. Therefore, this study aims to determine whether ALIF or PLIF/TLIF is a more cost-effective procedure for treating degenerative spine disease using a national database and microsimulations model.

Methods: A Markov decision model was utilized to investigate progression between health states for adults (18+) with degenerative spine disease undergoing either ALIF or PLIF/TLIF. Utilities and costs were derived from published reports. TriNetX, a nationwide platform containing de-identified electronic health record information from 118 million patients, was utilized to determine transition probabilities including two-week postoperative medical complication rates and two-year revision rates for both surgical approaches. 100,000 Monte Carlo microsimulations were performed to model quality-adjusted-life-years (QALYs) and healthcare costs over two years following surgery. The incremental cost-effectiveness ratio (ICER) was calculated.

Results: From the TriNetX database, the two-week medical complication rate was 6.93% and 8.35% for ALIF and PLIF/TLIF, respectively. Two-year revision rates were 6.11% and 4.79% for ALIF and PLIF/TLIF, respectively. Modeling showed a similar average individual two-year utility (1.204 vs. 1.203 QALYs) while cost ($65,894 vs. $75,972) favored PLIF/TLIF over ALIF. The ICER demonstrated that each QALY would cost $68,813,793 more for ALIF compared to PLIF/TLIF.

Conclusion : Modeling reveals that ALIF and PLIF/TLIF have relatively identical two-year utility. However, since PLIF/TLIF is considered a lower-cost procedure, it is therefore a more cost-effective option.