What Does A Lump On The Thigh Indicate?

My husband was in a motorcycle accident when an Suv ran a red light and hit him. He was knocked sideways off his bike, rolled 2 or 3 times and landed on his left side. In the ER he was Xrayed and they did a CT scan. His left inner pelvis is fractured, no other broken bones, but there is a lot of bruising and a large bulge on his outer left thigh. His pain is minimal, except when trying to stand or sit up but, using a walker, he's able to get back and forth to the bathroom, and walks around the house every few hours to keep exercising it like the Ortho Dr. told him to do. My question is; what do you think is causing the large bulge on his outer thigh? There is some numbness and bruising; but he has no fever, no nausea, and no pain unless he's standing up or sitting in a chair. What do you think?