Your discomfort is usually caused by an injury to one of the tissues in your leg that connect to your groin, such as a torn or strained muscle, ligament, or tendon. The term "groin strain" generally refers to torn or overstretched adductor muscles on the inside of the thigh. These muscles play a role in pulling your leg inward toward your body when you stand up straight. A strained hamstring is another common muscle injury in this area. Pain may also come from other sources such as arthritis, bone tumors, or venous stasis disease. The symptoms of a groin strain include pain when walking or standing that is particularly severe when you rise up onto your toes or try to bend your knee more than 90 degrees. You may also have pain when sitting for a long period of time. Other symptoms include difficulty sleeping at night because of pain, pain when coughing or sneezing, pain when lifting objects over your head, and pain when moving your leg too far or fast beyond what is normal for you. A sports medicine doctor can diagnose many types of injuries including strains, tears, and fractures. He or she will conduct a complete medical history and physical examination before recommending treatments. Your doctor may order tests if there is suspicion of trauma, infection, or cancer. In some cases, surgery is required to repair damaged tissue.