Osteoid osteoma is treated primarily by radiofrequency (RF) ablation. However, there is little information about the distribution of heat in bone during the procedure and its safety. We constructed a model of osteoid osteoma to assess the distribution of heat in bone and to define the margins of safety for ablation. Cavities were drilled in cadaver bovine bones and filled with a liver homogenate to simulate the tumour matrix. Temperature-sensing probes were placed in the bone in a radial fashion away from the cavities. RF ablation was performed 107 times in tumours < 10 mm in diameter (72 of which were in cortical bone, 35 in cancellous bone), and 41 times in cortical bone with models > 10 mm in diameter. Significantly higher temperatures were found in cancellous bone than in cortical bone (p < 0.05). For lesions up to 10 mm in diameter, in both bone types, the temperature varied directly with the size of the tumour (p < 0.05), and inversely with the distance from it. Tumours of > 10 mm in diameter showed a trend similar to those of smaller lesions. No temperature rise was seen beyond 12 mm from the edge of a cortical tumour of any size. Formulae were developed to predict the expected temperature in the bone during ablation.
Cite this article: Bone Joint J 2014; 96-B:677–83
- Osteoid osteoma
- Radiofrequency ablation
- Heat distribution in bone
- Benign bone tumours
- Minimally invasive surgery
- Temperature prediction
We would like to thank all those who contributed to this project: Professor N. S. Goldberg, S. Yeffet-Halevi and I. Nissenabum from the experimental radiology laboratory for their assistance with the experiments; T. Bdolah-Abraham and A. Daskal from the Hadassah-Hebrew University Medical School and the Hospital’s Department of Orthopedic Surgery for statistical analysis; and S. Fraifeld, senior technical writer at Hadassah, for editorial assistance during preparation of the manuscript. No financial support was received in support of this study. Research was performed at the Hadassah-Hebrew University Medical Center, in the Departments of Orthopedic Surgery and Radiology.
No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article.
This article was primary edited by G. Scott and first proof edited by J. Scott.
- Received July 26, 2013.
- Accepted February 7, 2014.
- ©2014 The British Editorial Society of Bone & Joint Surgery