In Reply: Are There Differences in 2-Year Outcomes Between 2-Level Anterior Cervical Diskectomy and Fusion Versus Single-Level Anterior Cervical Corpectomy and Fusion to Treat Cervical Myelopathy? A Quality Outcomes Database Study

To the Editor: We thank the authors of the recent letter1 commenting on our study, “Are There Differences in 2-Year Outcomes Between 2-Level Anterior Cervical Diskectomy and Fusion Versus Single-Level Anterior Cervical Corpectomy and Fusion to Treat Cervical Myelopathy? A Quality Outcomes Database Study.”2 We appreciate the opportunity to clarify the scope, rationale, and clinical implications of our findings. First, the letter raises a key point about the surgical indications for 2-level anterior cervical discectomy and fusion (ACDF) vs single-level anterior cervical corpectomy and fusion (ACCF). We agree that these procedures are not universally interchangeable in all clinical scenarios, and our article acknowledges that surgeon selection is influenced by anatomic considerations and location of the compressive pathology. In fact, patients in the ACCF cohort demonstrated significantly worse baseline myelopathy scores, greater comorbidity burden, and more frequent ambulation dependence, reflecting the clinical tendency to reserve ACCF for more severe or complex disease. Conversely, ACDF patients had higher rates of radicular motor deficits and arm pain, consistent with pathology more localized to the intervertebral disc level. The study's primary objective was not to suggest that these procedures are equivalent in all indications, but rather to determine whether both operations achieve comparable, clinically meaningful improvements in patient-reported outcome measures (PROMs) for cervical spondylotic myelopathy. Our investigation is the first large, multicenter, prospectively collected series with 2-year follow-up and minimum clinically important difference analysis of PROMs, which offers practical insight into the long-term functional outcomes of each approach. Second, the letter notes that titanium mesh cage subsidence and estimated blood loss are more frequent with ACCF. Our study confirmed higher estimated blood loss and longer hospital length of stay in the ACCF cohort, in alignment with prior literature. However, we found no significant difference in reoperation rates, nonroutine discharges, or 2-year PROMs, suggesting that while single-level ACCF is associated with higher perioperative morbidity, these differences do not translate into inferior long-term patient-reported outcomes. Furthermore, the letter's discussion of 3D-printed vertebral bodies highlights an evolving potential solution to subsidence, but our study's goal was to evaluate functional outcomes within current standard practice patterns, rather than to test novel devices. Finally, the concern that PROM comparison may lack practical significance due to differing baseline disease severity is addressed by our use of multivariable regression analyses. After adjusting for confounders, there was no significant difference in minimum clinically important difference achievement between 2-level ACDF and single-level ACCF at 3, 12, or 24 months. These findings reinforce that, in cases where either procedure is reasonable and clinical equipoise exists, both approaches can yield durable, meaningful improvements in PROMs. In conclusion, we agree that individualized surgical decision-making—guided by radiographic findings, cervical spondylotic myelopathy disease severity, and patient-specific factors—remains crucial. Our study does not argue that ACDF and ACCF are universally interchangeable, but it provides high-quality evidence that both procedures achieve comparable long-term functional outcomes, informing patient counseling and risk-benefit discussions when either surgical approach is an option.