The American Academy of Orthopedic Surgeons (AAOS) suggests that you see a health care provider if you have any of the following symptoms after a shoulder injury:

  • Continuous pain
  • Stiff shoulder
  • Feeling as if your shoulder could pop out or slide out of the socket
  • Decrease in shoulder strength or movement so that you cannot carry on with daily activities

Treatment for most shoulder injuries is rest and ice several times a day for 20 minutes and over-the-counter or prescribed anti-inflammatory medications. If these don't work, your health care provider might suggest strengthening exercises.

See a doctor immediately if you cannot lift your arm or if the shoulder is very painful, swollen and discolored. Your shoulder may be dislocated.

Knee injuries

The knee joins the lower end of the thighbone (femur), the shinbone (tibia) and the kneecap (patella). It is the largest joint in the body and bears much of the body's weight. Large ligaments connect the bones and stabilize the joint. Cartilage (meniscus) forms a cushion between the bones and absorbs shock during motion.

Common athletic injuries to knees involve blows to the knee, and twisting, jumping, slowing down when running and changing directions. Most often, it is the ligaments of the knee that are injured. Sports in which knee injuries are common are basketball, skiing and those that require athletic shoes with cleats.

Symptoms that require medical attention after a knee injury:

  • Pain accompanied by swelling or redness
  • Deformed joint
  • Pain over the kneecap
  • Inability to stand (knee "buckles")
  • Difficulty walking or inability to walk
  • Knee "locks" and won't bend
  • Hearing a "pop" when the knee was injured

For minor pain, try RICE: Rest, Ice, Compression and Elevation. Your health care provider might suggest over-the-counter or a prescribed anti-inflammatory medication. If this does not work, see your provider. Further treatment will depend on the cause of knee pain.

Source: http://resources.purematters.com/fitness/sports-injuries/sports-injuries-when-to-call-the-doc