Rare diseases · Sign or symptom
Osteochondroma
HP:0030431
What it means
A cartilage capped bony outgrowth of a long bone. Osteochondroma arises on the external surface of bone containing a marrow cavity that is continuous with that of the underlying bone.
Rare diseases that can present with this3
The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.
Part of the broader category
Also called: Osteocartilaginous exostoses · Osteochondromas
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Start free with EleplanThis page uses the Human Phenotype Ontology (2026-06-23) — Human Phenotype Ontology Consortium, hpo.jax.org. Disease associations from Orphanet (INSERM), CC BY 4.0. Content is educational and is not medical advice.