(HealthDay News) -- The collarbone doesn't completely harden until about age 20 years. This makes younger people -- especially participants in contact sports -- more susceptible to a broken collarbone, the American Academy of Orthopaedic Surgeons says.

The academy says common symptoms of a broken collarbone include:

• Having a shoulder that droops.
• Being in too much pain to lift one or both arms.
• Feeling a "grinding" as you try to lift an arm.
• Feeling pain when touching the collarbone.
• Detecting an abnormal bump or swelling on the collarbone.