Which of the following is associated with ‘spalding sign’?
**Spalding's Sign**
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**Core Concept**
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Spalding's sign is a radiological finding associated with osteosarcoma, a primary malignant bone tumor. It refers to the displacement of the metaphysis of the bone by the tumor, resulting in a characteristic appearance on X-rays. This sign is named after George Henry Makin Spalding, who first described it in 1911.
**Why the Correct Answer is Right**
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Spalding's sign is a result of the rapid growth of the osteosarcoma tumor, which causes the metaphysis of the bone to be pushed away from the growth plate. This displacement leads to a characteristic "Codman triangle" on X-rays, which is a triangular area of new bone formation at the junction of the tumor and the normal bone. The tumor also causes the soft tissue to become swollen, which can be visible on X-rays.
**Why Each Wrong Option is Incorrect**
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**Option A:** This option is incorrect because it is not related to Spalding's sign. While osteosarcoma is a type of bone cancer, this option does not describe a characteristic feature of the tumor.
**Option B:** This option is incorrect because it is associated with another type of bone tumor, Ewing's sarcoma. Ewing's sarcoma is a different type of malignant bone tumor that can cause a variety of radiological findings, but it is not associated with Spalding's sign.
**Option C:** This option is incorrect because it is a general term that refers to a variety of bone tumors, including both benign and malignant types. While some bone tumors may cause displacement of the metaphysis, not all of them are associated with Spalding's sign.
**Clinical Pearl / High-Yield Fact**
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Spalding's sign is an important radiological finding that can help diagnose osteosarcoma. It is essential for radiologists and clinicians to be aware of this sign, as it can aid in the early detection and treatment of this aggressive bone tumor.
**Correct Answer:** D.