Hematomas can form under the skin after impact, leading to swelling, discoloration, and pressure

https://cesarympt125.capitaljays.com/posts/the-impact-of-chiropractic-care-on-long-term-recovery-after-an-accident

Hematomas can form under the skin after impact, leading to swelling, discoloration, and pressure, sometimes needing drainage if large and painful.