The shoulder is a very complex region that is comprised of multiple joints and muscle attachments, a strong joint capsular ligament, and multiple nerves and blood vessels that pass into the arm to bring motor and sensory function to the hand and fingers. One condition of the shoulder that may drive a patient to seek chiropractic care is entrapment neuropathy of the suprascapular nerve. What is this condition? How does it occur? What treatment/s can help reduce pain and improve function?
The suprascapular nerve originates from the C5 and C6 cervical nerve roots shortly after they exit the spine and merge together forming the upper trunk of the brachial plexus (a complex of multiple merging nerves). The suprascapular nerve then branches off and supplies motor function to two of the four rotator cuff muscles—the supraspinatus (which starts shoulder abduction and lifts the arm up sideways) and the infraspinatus (the main external rotator of the shoulder).
The nerve can become entrapped or pinched from a direct blow to the area between the neck and shoulder (like from a football tackle or from a fall), wearing a heavy backpack, or from a job or leisure activities that feature overhead motions. The current research suggests that suprascapular nerve entrapment may account for up to 2% of all cases of shoulder pain, though in some groups, such as athletes, it may be responsible for up to a third of shoulder pain cases.
A complication of a suprascapular nerve problem is that it often co-occurs with other conditions and may not be diagnosed right away as treatment may focus on more common issues, such as a rotator cuff tear. To specifically identify a suprascapular nerve injury, an electromyography/nerve conduction velocity (EMG/NCV) may be necessary.
Depending on the cause of entrapment, treatment may involve rest; ice; exercise to strengthen specific muscles in the shoulder, neck, or upper back; and manual therapies. If the patient does not respond to this approach, they may be referred to an allied healthcare provider for additional treatment. While most cases respond to conservative care, an arthroscopic surgical procedure may be necessary in some circumstances.