Muscle contusions from seat belts or impact cause deep tenderness and bruising, often resolving with rest, ice

https://cesarympt125.capitaljays.com/posts/car-accident-chiropractic-care-what-a-6-week-plan-looks-like

Muscle contusions from seat belts or impact cause deep tenderness and bruising, often resolving with rest, ice, compression, and gradual activity.