Letter to the Editor Regarding “Complications in Full-Endoscopic Posterior Cervical Surgery: A Review of the Literature and Preventive Strategies”

Dear Editor,

We read with great interest the recent article by Kotheeranurak et al., titled “Complications in Full-Endoscopic Posterior Cervical Surgery: A Review of the Literature and Preventive Strategies.” ¹ As our institution is currently developing clinical trials and quality improvement interventions focused on full-endoscopic procedures, we are particularly grateful for the insights and recommendations presented in this work. We commend the authors for their contribution and would like to offer the following observations.

Firstly, the authors present individual study data in Table 2, showing complication counts and rates for each study. ¹ Table 3 then summarizes this information and introduces an estimated overall complication rate. ¹ However, providing more detail about the calculation methods for these overall rates would enhance clarity for readers. Based on the estimated rates presented in Table 3 and the accompanying footnotes, we assume the authors used simple pooling to calculate global incidence rates. ¹ This approach would involve dividing the total number of complications across all studies by the total sample size of 1921 patients. ² If simple pooling was indeed used, this raises significant concerns. This method is generally discouraged, as it fails to weight individual studies, implying no meaningful differences exist between studies and for some outcomes, risks producing paradoxical results. ³

Secondly, we looked for clinical trial registrations associated with the prospective studies, hoping to verify whether complications and assessment timepoints had been predefined. However, we were unable to find any. In the absence of such information, the reliability of the reported complication rates may be limited. This finding underscores the critical need for improved standardization in how complications are defined, assessed, and reported in clinical studies. ⁴ Encouraging developments in this direction include the creation and implementation of the Clavien-Dindo classification and the Comprehensive Complication Index.^5-7 Future studies should incorporate these tools along with predetermined assessment time-points. These considerations could improve surgical safety evaluation and provide better metrics for comparing the frequency and magnitude of complications, as well as a more thorough, longitudinal assessment of morbidity of full-endoscopic cervical interventions.^4,7

Finally, we would like to thank Kotheeranurak and colleagues for their valuable contribution. We believe that increased awareness of full-endoscopic cervical spine surgery complications, combined with the proposed preventive strategies, will enhance the safety of these procedures and the quality of care provided to patients.