We read the article entitled “Indirect foraminal decompression and improvement in the lumbar alignment after percutaneous cement discoplasty” with great interest. The authors evaluate the effects of percutaneous cement discoplasty (PCD) on spinopelvic radiological parameters and their associations with the clinical outcome. This is interesting since it further improved the evaluation system of PCD. We appreciate the tremendous work by the authors. But also we have some concerns regarding the study:

  1. 1.

    For measuring spinopelvic radiological parameters, especially for lumbar lordosis (LL), pelvic tilt (PT), sacral slope (SS), L4–L5 intervertebral angle (IVA4-5), the full-spine lateral standing films are difficult to be replaced. Even though the study used the lumbar standing X-rays and the author also explained it in the discussion section, it may still be impossible to avoid the deviations in results and even influence conclusions.

  2. 2.

    The author points out that the cement intake of the disc spaces varies in a wide range (3–10 ml), but did not explain relationship of cement intake and vacuum phenomenon. We think the difference in cement intake may directly lead to changes in segmental parameters such as segmental lordosis, segmental scoliosis, disc height anterior/posterior, interpedicular height. We have observed a difference in segmental parameters in the patients who underwent oblique lateral interbody fusion (the principle is indirect decompression, the same as PCD) with different sizes of cage. But we have no conclusion yet.

  3. 3.

    The authors found that the change in LBP significantly correlated with the degree of segmental scoliosis (sS) correction (ρ = 0.32, p < .001). We found 19 (68%) patients in this study underwent a multilevels PCD. How did the result above get from these patients? Can we understand that all sS in one patient with a multilevels PCD have correlation consistently with his/her change in LBP (ρ = 0.32, p < .001)? If we can, how to achieve it?

We appreciate the work by the authors again. It provides ideas for the image evaluation of PCD. However, several issues mentioned above may need more complete considerations.