Teenager quartbreback with shoulder pain after throwing

Patient: Hello i am 16 years old and have been a quarterback for about 5 years on the off season i typically throw every sunday for 3 hours and recently (past month) the first hour of throwing (after thorough and correct warmup) i have exctuciating pain in my right shoulder as i throw, it feels very weak and i have nothing behind it. about after an hour and 45 minutes my shoulder feels amazing and i can throw harder and better then ever. the next day it always feels tight and stiff and when i do anything over my head (ex:pullups) i have horrible pain. What can this possibly be?

Doctor: There are several causes of arm-shoulder pain; one of the most common is the Rotator Cuff tendinitis, tear and/or Impin ngement and this seems to correspond with the description that you made of your pain, moreover with your previous history, meaning a lot of throwing. The rotator cuff is a group of tendons that support the shoulder. You might be having a kind of Repetitive stress injury (RSIs), these are injuries that happen when too much stress is placed on a part of the body, resulting in inflammation (pain and swelling), muscle strain, or tissue damage. This stress generally occurs from repeating the same movements over and over again, with no enough healing time so they are also called “overuse syndrome”. The concept is that overuse injury is associated with repeated challenge without sufficient recovery time, and this is true for any sport or activity in which you exceed the guidelines and your own limits or capacities. Overuse injuries or repetitive motion injuries make up over 50% of all athletic-related injuries seen by doctors.  Conservative treatment of the Rotator Cuff tendonitis involves: physical therapy to control pain and keep range of motion of the shoulder, avoidance of painful movements and activities; anti-inflammatory medication (i.e.: “Advil”, “Aleve).