The most commonly injured joint in the human body has to be the shoulder. There are many reasons why the shoulder joint is injured more than any other. It has very little support from any other bone. Which is good because then we have a larger range of motion in that joint than any other joint in the body. So how does the shoulder stay where it is? Ligaments, muscle and tendon. We have several tendons and several muscles that hold the shoulder joint together. Hence, the common rotator cuff injury.
The rotator cuff has four muscles: supraspinatus, subscapularis, teres minor and the infraspinatus. Supraspinatus is the most commonly injured of the four muscles. It is usually injured in a movement that you have done a thousand times with no injury. Then why did you get this injury? It could be very complicated to very simple.
You did not warm up properly.
Too much weight without proper stabilization. (i.e. too much weight on lateral raises)
Nerve impingement which does not let the muscles respond as they should.
All of these can be avoided. Proper technique in the lift, proper warm up and removal of the Vertebral Subluxation Complex (What I do for a living as a Chiropractor) will all help. These suggestions will allow proper nerve flow, so that your mind and your body are working as one.
Proper alignment, rehab and rest are essential in the recovery of a shoulder injury. Don't rush it. It takes time - 6 weeks to 6 months - for proper recovery, or you are destined to repeat it. Remember in this equation of rehab and rest is proper nutrition. If you don't have proper nutrition, you will not build a sound body and mind.
Note: Shoulder pain can also be related to other ailments of the heart, lungs, spleen (left shoulder only), gallbladder, stomach and duodenum, pancreas and nerves.