Letter to “Incidence of and Risk Factors for Neurological Deficits Associated With Percutaneous Vertebral Augmentation”

To the Editor,

We read the recent article by Zhu et al ¹ with great interest. The authors investigated the incidence and risk factors for neurological deficits following percutaneous vertebral augmentation (PVA) in a sizeable cohort. Their finding of a low but not negligible rate of neurological complications (0.32%), with significantly higher risk in patients with neoplastic vertebral fractures, is timely and relevant. However, several critical aspects warrant further discussion.

First, while the study rightly identifies neoplastic lesions as increasing the risk for neurological complications due to the likelihood of polymethylmethacrylate (PMMA) leakage, the surgical technique and intraoperative imaging modalities utilized are only briefly described. Modern practice increasingly relies on multimodal intraoperative imaging-including real-time fluoroscopy and, in some centers, cone-beam CT-to detect cement leak early and adjust the procedure accordingly. ² In the present study, however, postoperative X-ray (rather than higher-sensitivity CT) was used to detect PMMA leaks, and only leaks causing clinical deficits would prompt quick intervention. This approach likely underestimates both overall and potentially harmful cement extravasations. ³ Asymptomatic PMMA leakage can still bear clinical consequences over time, underscoring the value of routine CT assessment in risk evaluation.

Second, the technical detail regarding puncture method and cement injection protocols in different spine levels was insufficient. The discussion suggests that a unilateral approach and lower cement volume were preferred in the thoracic spine, which may reduce complication risk, yet no data is provided on the standardized indications for approach selection or cement volume. Previous research demonstrates that cement volume, viscosity, and injection speed significantly affect leakage rates and complication profiles. ⁴ Without standardized protocols or at least detailed parameter reporting, external reproducibility and risk interpretation are limited.

Third, selection criteria for percutaneous vertebroplasty (PVP) vs kyphoplasty (PKP) are not clearly defined. Notably, there were no neurological deficits reported in PKP procedures in this cohort. However, the smaller sample size of PKP and lack of subgroup analysis preclude definitive risk assessment between techniques. Systematic reviews and large meta-analyses have found that PKP typically has a lower risk of cement leakage compared to PVP, especially in cases with posterior wall defects. ⁵ The absence of neurologic complications in PKP within this study may reflect selection bias or underreporting rather than a true difference in safety profile.

In summary, while this large single-center study contributes useful data regarding the incidence and risk factors of neurologic complications following PVA, methodological constraints -especially regarding imaging, procedural technique, and thorough complication ascertainment -limit the generalizability and risk stratification utility of the results.