The Heat Line for Burned Bone

HomeRadiologyVol. 314, No. 2 PreviousNext Reviews and CommentaryFree AccessImages in RadiologyThe Heat Line for Burned BoneXingshun Zhou , Qiaoling ZhangXingshun Zhou , Qiaoling ZhangAuthor AffiliationsFrom the Department of Radiology, No 926 Hospital, Joint Logistics Support Force of the People's Liberation Army, Kaiyuan 661699, Yunnan, China.Address correspondence to X.Z. (email: [email protected]).Xingshun Zhou Qiaoling ZhangPublished Online:Feb 4 2025https://doi.org/10.1148/radiol.241883MoreSectionsPDF ToolsAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookXLinked In A 45-year-old man experienced a direct flame burn to his right knee following syncope; he underwent escharotomy and received a skin xenograft and treatment with fluid replacement and antibiotics at another hospital. Twenty-one days after the burn injury, he presented to our hospital for further treatment. Dual-energy CT with volume rendering showed multiple absent muscles and ligaments in the right knee, and some bones were exposed. Color-coded virtual noncalcium images from dual-energy CT demonstrated a clear demarcation between injured and unaffected bone (Figure, A). Proton density–weighted MRI likewise showed a line with high signal intensity between the abnormal bone and the normal bone (Figure, B).Images in a 45-year-old man with a burn injury to his right knee joint. Sagittal (A) virtual noncalcium image from dual-energy CT and (B) proton density–weighted MRI scan show the heat line (arrow) in the medullary cavity of the tibia, between bone injured by fire (arrowhead) and unaffected bone (*). Insets show axial images. (C) Photograph before surgery (left) shows the necrotic portions of the bone (arrows), which appear brown following calcination. Photograph after surgery (right) reveals normal bone (*) after removal of the necrotic tissue.Download as PowerPoint Surgery was subsequently performed, and the extent of the necrotic bone removed was consistent with image-based planning (Figure, C). It was confirmed intraoperatively that the linear shadow seen at imaging was the initial transition between unaltered and thermally altered bone, known as the heat line (1). After multiple flap surgeries, the patient was in good condition at 6-month follow-up. For patients with severe bone burns, imaging can provide important information for surgical planning. Both MRI and dual-energy CT bone marrow imaging technology can clearly depict a heat line. CT has the advantages of short scanning time and multifunctional reconstruction, which not only clearly depicts soft tissue injury, but also can help identify the area and volume of the burned bone. The shorter acquisition time of dual-energy CT may be particularly advantageous in patients who cannot tolerate protracted imaging.Disclosures of conflicts of interest: X.Z. No relevant relationships. Q.Z. No relevant relationships.Reference1. Keough N, L'Abbé EN, Steyn M, Pretorius S. Assessment of skeletal changes after post-mortem exposure to fire as an indicator of decomposition stage. Forensic Sci Int 2015;246:17–24. Medline Google ScholarArticle HistoryReceived: June 26 2024Revision requested: Aug 5 2024Revision received: Aug 20 2024Accepted: Sept 10 2024Published online: Feb 04 2025 FiguresReferencesRelatedDetails Vol. 314, No. 2 Metrics Altmetric Score PDF download