Letter to the editor to comment on “Factors associated with improvement in ankle dorsiflexion after transfibular total ankle arthroplasty”

Dear editor,

We have studied a research paper titled “Factors associated with improvement in ankle dorsiflexion after transfibular total ankle arthroplasty”, in Japan, which was published in a column of your esteemed journal written by Song Ho Chan et al., caught our curiosity .

We wholeheartedly appreciate their cautious radiographic evaluation of ankle dorsiflexion after transfibular Total Ankle Arthroplasty (TAA) and for addressing a significant medical concern. The study provides valuable insights into additional treatments and implant placement that may impact postoperative motion. The authors’ emphasis on ankle dorsiflexion after transfibular total ankle arthroplasty is a significant contribution to the field since it aligns with evidence-based treatment. Your study fills a crucial gap in transfibular TAA research by giving valuable details. The simple presentation of radiography findings makes complex data easier to comprehend .

We sincerely like to draw attention to a few methodological concerns. First, individuals were divided into groups based on a ≥ 5° improvement in dorsiflexion. Ankle dorsiflexion is a continuous variable, and dichotomisation could impact statistical significance while concealing clinically relevant gradients of development, despite previous studies demonstrating this .

Second, despite the fact that radiographic outcomes were examined every six months, the reported median follow-up was 26 months with significant variability. According to previous studies, ankle range of motion after TAA may change throughout the first 12–24 months, which could affect how long-term benefits are viewed .

Third, the group with increased dorsiflexion had a significantly higher rate of Achilles tendon lengthening. This method’s uneven distribution may affect connections to implant depth, angular parameters, and osteophyte removal because it directly increases ankle dorsiflexion. Multivariable modelling may allow for the identification of distinct elements influencing dorsiflexion progression .

Furthermore, no intra-observer reliability has been identified, despite the fact that all radiographic measures were performed by a single trained observer. Reliability statistics should be presented when key conclusions are reliant on angle measurements. These findings of the research should have had a major effect on the field .

In conclusion, your study clearly identifies crucial parameters that promote ankle movement following surgery. The utilisation of precise X-ray measurements is an appropriate and accurate strategy; we appreciate your excellent guidance. We applaud the authors’ dedicated effort and believe their findings provide an important foundation for future research targeted at optimising functional outcomes after transfibular total ankle arthroplasty.