Differentiating subcutaneous swellings

What it is

A swelling under the skin is placed by two things: whether it is attached to the skin, and whether it gives the slippage sign. The DDx put up for such a swelling is a lipoma, a sebaceous cyst, and a lymph node, for example a sub-occipital one. For a neck swelling the DDx put up is goiter, lipoma, lymph node with lymphoma behind it, and aneurysm.

How it presents

A lipoma gives the slippage sign and is not attached to the skin. A sebaceous cyst has a punctum and is attached to the skin, so the punctum and the skin go together. A lipoma is also listed among the skin manifestations of spina bifida occulta, and hair and a birth mark are listed with it, spina bifida occulta being a failure of fusion of the vertebral arch that is often an incidental finding on x-ray.