Sprained Wrist
This is little Steven Argyle in 1982. Now hes grown up handsome, buff, talented,...
This is little Steven Argyle in 1982. Now he's grown up handsome, buff, talented, and rich (and married).
Scenario:
Most wrist sprains occur during a fall. As you head towards the ground, it's normal to put your hands out to catch yourself. If your body has enough rotational inertia to carry you on into a tumble, the wrist will be bent backwards, resulting in a sprain.

Description:
A sprain is a stretching injury to ligaments (the bands of tough tissue that control which direction joints can bend). A minor wrist sprain usually doesn't swell at all. If you see a bulge of swelling, chances are you've done something really BAD. With a wrist sprain that you could treat at home, there should only be pain at the extremes of motion -- bent all the way back or all the way down. If the wrist hurts with tiny wiggles, you should go have an x-ray.

Concerns:
What seems to be a wrist sprain may really be a fracture. Be VERY careful. Even a minor wrist sprain can take a long time to heal. If there are signs of serious injury, you should have the doctor help you.

See the doctor if:
    there's any swelling or deformity
    there's pain when the wrist is resting (after the first hour)
    you can't move the joint fully
    there's pain with motion of the fingers
    there's pain with small motions of the wrist
    there's numbness or weakness below the injured area.

Ice on the wrist.
Ice on the wrist.
Immediate care:
The treatment of a sprain is "RICE:" Rest, Ice, Compress, and Elevate. Immediately elevate the injured part. If possible, apply ice directly to the injury.
Once the area is thoroughly cooled, apply an elastic wrap to compress the injury. Cross the wrist at an angle a couple of times, wrapping up around the web between the thumb and index finger.

Coban wrap is a light, efficient wrap that you can carry in your biking backpack. It compresses and stabilizes sprains, and can hold a dressing over cuts and scrapes while you ride your bike back to civilization.

Compression wrap.
Compression wrap.
Rest, ice, compression, elevation.
Rest, ice, compression, elevation.
Ongoing care:
For the first 48 hours, repeat ice and elevation 1/4 of the time (for example, 30 minutes of ice every two hours). Keep support on the wrist
As the pain subsides, return to activities. The rule is: "If it hurts, don't do it." You can usually stop using the elastic wrap after 2 to 3 days. If the wrist remains weak or painful in routine use, go to the doctor.

Wrist rehab:
After the first few days, start rehab exercises.
Isometric strengthening: Grip a rubber ball with your fingers, without moving the wrist. Squeeze for about 30 seconds, then  release. Repeat this 20 times, twice a day.
Range of motion: Warm the wrist for 10 minutes (heating pad or sink of warm water). Gently bend the wrist back until it begins to feel uncomfortable, then hold the stretch for 30 seconds. Rest for a minute, then do it again. Repeat 5 times. Now bend downward and hold for 30 seconds, rest a minute, and repeat 5 times. If the wrist has increased discomfort after the exercises, ice the wrist for 20 minutes after the exercises. Do the exercises twice a day.

Get back to activity when the wrist says it's OK.
Get back to activity when the wrist says it's OK.
Continued support if the wrist is still uncomfortable.
Continued support if the wrist is still uncomfortable.
The wrist may need some support for a few weeks, particularly if you'll be lifting. A medical supply store can supply you with a strong splint.

Photo shows a commercial removable wrist splint. Pull-on elastic sleeves aren't truly splints, and don't give much support. If you have a significant sprain, get a splint with metal strips.