What causes a hand to swell after a fall? i fell and my hand is swollen like a boxing glove. can't move it or touch it.

Probably a broken bo: A Colles fracture or other broken bone. See an orthopedic DR TODAY or go to ER. At least a severe sprain.

Swollen hand: You may have fractured your wrist or hand. See your doctor or go to the ER for an xray. In the meantime you can use ice to reduce the swelling

Fracture: Certainly the fall with a lot of swelling makes me concerned you might have a fracture. You need to see your doctor get x-rays, you may need a cast. Be certain to get tested for Osteoporosis because if you have a fracture there's a great risk that you also have osteoporosis. A fall is an accident but a fracture is Osteoporosis

Fracture: A fracture must be considered with those symptoms which occurred after a fall. Your physician should examine you. Apply ice and elevate your hand to minimize swelling in the meantime.

Sure nothing broke: I strongly recommend that you see your doctor to get the hand checked out. Any type of tissue injury will cause swelling after a fall but in the elderly we worry about fracture due to increased risk. The swelling could be due to minor sprain or even bruising but it's very hard to tell without seeing the affected area.