There are many reasons why the shoulder is one of the most delicate and frequently injured joints in the human body. First of all, the shoulder is the 2nd worst lever system in the body, next to the hip joint. Because a person’s arm is so long, and the shoulder is so small, then it’s probably the worst lever in the body, taking everything into consideration. Additionally, the shoulder has an intricate ball and socket joint formation, which allows almost a “free” range of motion that spans up to 180 degrees. Some people that have hyper-mobile joints may actually be able to move their shoulders over the 180 degrees, as well.
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