We read with great interest the article titled “Predictors for second-stage posterior direct decompression after lateral lumbar interbody fusion: a review of five hundred fifty-seven patients in the past five years” by Jun Li et al. and would like to congratulate the authors for their study [1]. The authors conducted a radiological study to analyze the risk factors for second-stage posterior direct decompression through univariate and multivariable logistic regression model, which helped us better acknowledge the indication of lateral lumbar interbody fusion for lumbar spinal stenosis.

Although they have touched a highly pertinent topic in a scientific manner, the time is very important. We would like to point this out; the procedures may show clinical outcome in year or more [2]. However, from our previous experience, we observed that the clinical outcomes of indirect decompression were excellent, with the thecal sac expanding over time as confirmed via MRI. Even in the instance of severe stenosis, the median canal cross-sectional area (CSA) improved over time, increasing from 54.5 ± 19.2 mm2 pre-operatively to 84.7 ± 31.8 mm2 at three weeks post-operation and to 132.6 ± 37.5 mm2 at the last follow-up, an average 28.3 months later.

Nonetheless, the most critical aspect is to maintain this stabilization in the long term and ultimately achieve solid segmental arthrodesis. Thus, we believe that both “indirect decompression” and “stabilization” have pivotal roles in the treatment of lumbar stenosis.

Many of those PDD were likely unnecessary. The possible risk factor of failed indirect decompression includes osteoporosis. The patient of bone mineral density was no provided.

We respectfully appreciate that Jun Li et al. provided us with this important study. However, when perform the second-stage PDD procedure pertinent topic.