@muhammadrashidkhan61: Why do veins bulge and twist like this? Inside the vein are tiny one-way valves. Normally, they help blood move upward toward the heart. But when a valve does not close properly, some blood can flow backward and pool below it. That added pressure can stretch the vein, making it widen and twist under the skin. This is an educational animation, not a personal diagnosis. #medicalstudent #MedicalAnimation #Anatomy #healthtips #fyp