A quadricep contusion is a bruise of the thigh muscle caused by blunt force trauma. It results in bleeding within the muscle. Symptoms include swelling, tenderness, pain, and limited range of motion. Contusions are classified as mild, moderate, or severe depending on factors like range of knee flexion, ability to walk, and average time lost from activities. Treatment involves RICE (rest, ice, compression, and elevation), bracing, NSAIDs, and physical therapy starting with isometric exercises and stretching, then progressing to full range of motion and functional rehabilitation.