Unusual bone abnormalities from therapeutic ultrasound diathermy: a radiological case report.

This report describes bone marrow abnormalities arising as a consequence of therapeutic ultrasound diathermy, which are an uncommon diagnostic entity. Over the period from 2018 to 2023, 11 patients were identified that showed abnormalities of the bone marrow on MRI, as a direct result of ultrasound diathermy treatment. These abnormalities displayed consistent imaging features, characterized by areas of low T1W and high T2W signal intensity with well-demarcated geographic margins and central fatty areas, as can be seen in bone infarction. The imaging findings were localized in the superficial aspect of the bone, near the skin surface, corresponding to the site of ultrasound insonation. The clinical relevance of this report stems from the scarcity of documented cases and the unfamiliarity of this diagnostic entity among radiologists and orthopedic surgeons. The specificity of the imaging findings, their typical location, and the potential for resolution with cessation of the diathermy therapy reinforces the importance of this report. Recognition of this condition enables understanding potential adverse effects of ultrasound diathermy, increasing awareness regarding the importance of adhering to safe techniques and the use of this physical treatment modality in clinical practice. This information is also useful to athletic trainers, physical therapists, physical medicine and rehabilitation clinicians, and anyone who might perform ultrasound diathermy.