DDx of "pied" with lump on back of head and back of neck

There are several possible causes for a lump on the back of the head and back of the neck. However, without a physical examination and more information about the specific characteristics of the lump, it is difficult to provide a definitive diagnosis. Some potential causes could include:

1. Lipoma: A benign (non-cancerous) growth of fat cells that can develop under the skin. Lipomas are typically soft and movable to the touch.

2. Cyst: A sac-like structure filled with fluid or semi-solid material. Cysts can be caused by infections, blockages, or developmental abnormalities. They may be tender or painless, and their size can vary.

3. Lymphadenopathy: Enlarged lymph nodes due to an infection or an immune response. These enlarged lymph nodes can feel like lumps and are usually accompanied by other symptoms such as fatigue, fever, or sore throat.

4. Sebaceous cyst: Similar to other cysts, sebaceous cysts are formed due to the blockage of sebaceous glands, which are responsible for producing oil for the skin and hair. They are generally non-painful and can be moved beneath the skin.

5. Dermoid cyst: A type of cyst that contains tissues such as fat, hair, and sometimes even teeth. Dermoid cysts are usually present from birth and are typically painless.

6. Lipomatosis: A condition characterized by the presence of multiple lipomas throughout the body. Lipomatosis can lead to the development of lumps in various regions, including the back of the head and neck.

It is important to note that these are just a few possible causes and a thorough evaluation by a healthcare professional is necessary to determine the exact cause and provide appropriate treatment.