Re: Bobelyak M, Vaculik J, Stepan JJ. Bone mineral density assessment using Radiofrequency Echographic Mult Spectrometry (REMS) in patients before and after total hip replacement, Osteoporos Int 2025;https://doi.org/10.1007/s00198-025-07685-w and Re: Pocock N, Chan D. Editorial: Is REMS-BMD truly a measured parameter? A call for transparency and technical clarification, Osteoporos Int 2025;https://doi.org/10.1007/s00198-025-07699-4

We read with interest the article by Bobelyak and colleagues and the accompanying Editorial.However, we have serious concerns about the article's methodology and conclusions.The authors reported REMS-BMD measurements at the proximal femur in patients before and after hip arthroplasty and, based on minimal changes in BMD and variations observed with different anthropometric inputs, concluded that REMS-BMD is essentially derived from age, sex, and BMI rather than from ultrasound spectral data.This conclusion is not supported by the evidence provided, which highlight instead technical errors and misinterpretations of REMS operating principles, as detailed below.