This may be a sebaceous cyst. This type of bump develops when sebaceous glands are blocked. Sebum builds up and a bump develops. This bump can feel hard to touch. Sebum is naturally produced, so there usually is not inflammation.
Explanation:
The International Classification of Functioning, Disability and Health (ICF) is a framework for describing and organizing information on functioning and disability. It provides a standard language and a conceptual basis for the definition and measurement of health and disability.
Step 5 is what I would say sorry if that did not answer you question
