The lateral femoral cutaneous nerve receives sensation from the top of your thighs on each side. If the nerve is pinched or injured, it can cause pain, numbness, tingling or painful stinging in the front or outer part of your thigh(s). You may also have tenderness in your groin. During this injection, a small amount of numbing medicine with or without cortisone (steroid) is injected around this nerve. Although uncommon, risks may include bleeding, infection, nerve damage and allergic reaction to the medication.