Shoulder problems are common among athletes. These problems may be caused by trauma, but most come from overuse. Overloading the muscles and nearby soft tissues is easy to do when movements are repeated over and over.
The four muscles around the shoulder, called the rotator cuff, have been the subject of much research on shoulder strength. Recently, a new focus of study has come to light. It seems that the shoulder blade, also known as the scapula, has an important role in shoulder strength. Researchers want to know the strength of the shoulder when the scapula is in different positions. A round-shouldered or slouched posture puts the scapula in a forward position. This is called a protracted scapula.
Previous studies have shown that this position causes shoulder pain in many people. The protracted position narrows the space in the shoulder joint needed for movement, puts strain on the ligaments in the shoulder, and decreases shoulder strength. A group of physical therapists teamed up in a motion analysis lab to study this problem.
Ten adults with no shoulder or neck problems were tested. The strength of each person’s shoulder was measured with the scapula in three different positions: forward, in the middle or “neutral,” and pulled back or “retracted.”
The strength of the shoulder was less when the scapula was either pulled back or pushed forward. Strength was affected in equal amounts in these positions. Strength was best when the scapula was in the middle or neutral position.
The position of the scapula is important for shoulder function and strength. If the scapula is slouched too far forward or pulled too far back, shoulder motion and strength are reduced. This is an important finding for physical therapists working with patients on shoulder rehabilitation. Further studies are being done to test the strength of the shoulder with the arm straight forward versus out to the side. This information will help therapists plan treatment to strengthen the shoulder.