Which term describes a collection of blood under the skin?

• A. Edema
• B. Crepitus
• C. Hematoma
• D. Ecchymosis

Answer: (C)

Hematoma is the term for a localized collection of blood outside vessels within the tissues. When a blood vessel is damaged, blood leaks into surrounding tissue and pools, forming a lump under the skin that may be tender and change color as blood products break down. This is distinct from edema, which is swelling from fluid in tissue rather than blood, and from ecchymosis, which is skin discoloration (a bruise) caused by blood beneath the skin but not necessarily a discrete pocket of organized blood. Crepitus refers to a crackling sensation from air in soft tissues, not a blood collection. So the described finding fits hematoma.