Letter to the editor: “Osteoid osteoma of the talus: a clinical case report and literature review”

Dear Editor-in-Chief, We have read with great interest the article published in your esteemed journal by M. Diop et al[1], reporting a case of osteoid osteoma of the talar body. Based on our own experience in Orthopaedic Surgery and a review of the relevant literature, we would like to share a few reflections and constructive comments to foster further discussion among readers. The case is certainly interesting and highlights the potential for this lesion to be overlooked in the initial diagnosis assesment[1]. However, the images presented in the authors’ paper and transcribed here (Fig. 1) appear more consistent with an osteoblastoma rather than an osteoid osteoma. As mentioned in the classic article by Capanna et al[2], also cited by the authors, both tumors share similar histological characteristics; nevertheless, osteoid osteomas are typically smaller than 2 cm, whereas osteoblastomas usually exceed this size. In the reported case, the lesion measures approximately 4 cm.[2–4] Furthermore, the characteristic nidus typical of most osteoid osteomas is not identified in the radiological figures presented. Instead, the lesion is described and shown as osteolytic, with sclerotic margins and internal septations. For all of these reasons, we believe this lesion is actually an osteoblastoma. Figure 1.: Imaging studies of the left ankle included in the original publication. Plain radiographs in anteroposterior (left) and lateral (middle) projections, and a sagittal computed tomography section (right), show an osteolytic lesion of the talar body extending posteriorly, measuring approximately 4.0 cm in width and 4.5 cm in length, as estimated using the scale shown in the left image and the average size of adult ankle bones. As the figure is reproduced from Diop et al [1], no permission is required, as this is an open-access article. In addition, a detailed histological description of the lesion is lacking, as the authors only state that “the diagnosis of osteoid osteoma was confirmed by histology.” Although the images presented in the article appear consistent with the histological features of either an osteoblastoma or an osteoid osteoma, this work would greatly benefit from a more comprehensive histological description to facilitate its analysis and use in subsequent research[4]. Regarding the differential diagnosis, giant cell tumor and aneurysmal bone cyst would likely represent more frequent considerations, as the authors initially suggested, with osteoblastoma and other lesions being less likely. According to Capanna et al[2], osteoid osteoma of the talus is not particularly rare. Conversely, osteoblastomas are less common than osteoid osteomas and are rarely located in the talus, particularly in the talar body, as reported by Beytemür et al[5]. If the lesion is indeed an osteoblastoma, this would make the case even more notable, given the rarity of such tumors in this location[4]. With respect to treatment, the use of acrylic cement is more appropriate for giant cell tumors and metastases due to their higher propensity for recurrence[3]. However, this approach may be considered rather aggressive for an osteoblastoma, which has a lower recurrence rate.[6,7] Bone grafting might have been a suitable choice if the diagnosis had been confirmed prior to definitive treatment. A needle or incisional biopsy could also have been considered in the presence of diagnostic uncertainty to better guide optimal management[6]. We hope that our observations contribute to a more precise understanding of talar tumors and aid in clinical decision-making. We thank you very much for considering the publication of our contribution and look forward to the comments from both the authors and the editorial team, which may help clarify the diagnostic and therapeutic aspects of this interesting case.