Shoulder impingement results from an imbalance of muscle strength between the rotator cuff and the deltoid muscle. Activities that involve repetitive use, like shoveling snow, can cause muscle imbalance because the rotator cuff musculature can fatigue faster than the deltoid muscle. Shoulder stability comes from the balance between muscle groups because the bones in the shoulder provide little stability to the shoulder joint. Impingement results when the musculature of the rotator cuff is relatively weak compared to the very strong powerful deltoid muscle which is the primary mover of the shoulder.
A lot of times people don’t notice that anything’s wrong with their shoulder until the next day, or the day following an activity. When the inflammatory process ramps up, a person will begin to experience arm pain, but most of the time people can’t identify any specific event that could have caused this pain.
The shoulder is so dependent on the balance between muscle groups that subtle alterations in movement or activity can result in impingement syndrome. “How we choose to treat impingement depends on where the individual is at on the spectrum of pathology for impingement. Without significant structural injury, non-operative treatment is the rule, which may include physical therapy, a stretching program, or steroid injections. Surgical options are considered when irreversible changes have occurred that non-operative treatments cannot fix,” states orthopedic shoulder specialist, Dr. Scott Jacobson. A rotator cuff tear, for example, oftentimes does not respond to non-operative treatment and commonly requires surgical treatment.
“If I could encourage people to do any type of exercises to minimize the risk of impingement syndrome, it would be exercises to strengthen the rotator cuff,” says Jacobson. “It’s a lot easier to prevent the onset of impingement than it is to cure the problem once it starts hurting. If you can figure out a way to incorporate shoulder strengthening exercises into your regular activities, it’s very beneficial.”