What do baseball, tennis, and softball have in common? They are all spring sports that require intense overhead activity. Whether it be throwing or serving there is a potential for overuse and aggravation to the shoulder joint. Shoulder injuries are the fifth most common injury in high school athletes and while many of them are collision injuries; as many as 42% of them are non-contact injuries.
The shoulder is the most mobile joint in the human body, and because of this, there is a fragile equilibrium between stability and mobility. This is referred to as the “throwers dilemma”. To understand shoulder injuries in athletes one must first understand what is required to make a throw or hit a serve. First, the shoulder blade must be strong and moving properly around the ribcage. Without the strong stable platform of the scapula for the arm bone to move on, you will not achieve maximum velocity. If the arm does not move properly then you can be setting yourself up for injury. Second, is actual shoulder flexibility and range of motion (ROM). There is a structure in the shoulder called the capsule that allows just enough motion but prevents joint dislocation. But when it is repeatedly traumatized with throwing or serving it can become too tight or even too loose. It is worth noting however, that if you’re someone who participates frequently in an overhead sport your shoulder range of motion will change and not necessarily for the worse.
The final aspect of the throw to understand is the kinetic chain. The kinetic chain essentially refers to the transfer of forces from your feet to your wrist and everything in between. The kinetic chain can easily be ignored when athletes are having shoulder pain but many times the problem can be created or at least exacerbated by weakness or loss of flexibility in the legs and trunk. Research has shown that 54% of the force in a throw or serve comes from the leg, hip, and trunk. Training these frequently ignored areas can take stress off of the shoulder joint and simultaneously increase speed. This is especially important for adolescents who are participating in overhead sports because of the fact that they are still growing. As children grow they can become less flexible which can lead to less force production out of their bodies. So it is important to try and stay ahead of the growth curve with specific stretching and strengthening exercises.
What I am advocating is a preventative plan to decrease the possibility of injury. This may involve a detailed evaluation by a medical professional or simply an at home plan that focuses on flexibility first and secondly strength. It has never been more important than it is now, because kids are spending so much time playing one sport. Many of today’s youth sports are year around which means there is little time for rest or other sports which may help train flexibility and strength that one sport neglects. Also, Healthcare is more expensive today than ever before. With a preventative program you can hold on to more of your money, and keep your athlete on the field or court having fun.
John Oxley is a physical therapist at Huntington Physical Therapy. The focus of his practice is spine care and shoulder rehabilitation. You can reach him by emailing firstname.lastname@example.org