General and Systemic Histopathology, C601&C602
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Believe it or not this
is benign. If you look at the bone, it appears healthy with all cellular
constituents present. I wouldn't be surprised if in some slides there
is even active hematopoietic bone marrow present. Auto mechanics
get these often in their hands at sites of recurrent injury. See this slide with the virtual microscope. |
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This is one of those odd lesions for which numerous explanations abound. Always benign, it looks just like its name sounds. It is a focus of bone formation on the fascia, within the muscle or subcutaneous fat. Sounds odd, but fascial tissue has a wide range of possible reactions to injury. This probably started as an area of hemorrhage, then became partially organized and finally developed bone. In some lesions like this, it is possible to even see bone marrow with active hematopoiesis develop. |