The shoulder is a well-used and important joint. It allows you to move your arm at will and then bears the weight of objects you pick up, as well as the weight of your arm if you are reaching up or beyond your immediate reach. Because of the way the shoulder joint performs, if a nerve is compressed, it can cause significant pain and weakness in your shoulder and/or arm. The area where the nerve is also affects how your arm will react, so it's important that nerve compression of the shoulder be pinpointed and diagnosed as quickly as possible.
One type of nerve injury is called the suprascapular nerve impingement. Along the back of your neck runs the uppermost part of your spine. This is called the cervical spine and the vertebrae, the bones or discs that make up the spine, are numbered from C1 to C7, with C1 being the upper most and C7 being the last in this particular series. Nerves feed down the spine and branch out at the different vertebrael levels, with each level and nerves affecting a different part of the body. With suprascapular nerve impingement, the nerve that comes from between C5 and C6, which passes deep into the upper arm muscles and across the collarbone, is affected. Even this, however, has subsections that need to be diagnosed because there appears to be five different types according to the end location, called notches.
The two most common notches are the suprascapular notch and the spinoglenoid notch, usually caused by a narrowed tunnel though which the nerves pass, or some sort of blockage that presses on the nerves. The signs of these notches are shoulder pain in the back and side of the shoulder and perhaps difficulty raising your arm or turning it outwards (externally). If the pain has been around for a while, the muscles may start to atrophy, or waste away. When the doctor examines the shoulder, it may be tender and this tenderness may be relieved by an injection of anesthetic to the area.
To treat this, if there is no obvious reason causing the nerve pressure (seen by x-ray or further tests), there is no rush for surgery because there is nothing specific to work on. In this case, conservative management is usually the way to go. This may mean reducing the activity of the shoulder, using anti-inflammatory medications to help reduce swelling and relieve pain, and physiotherapy. If, after six months, there is no improvement, then it may be necessary for surgery. During the surgery, the surgeon relieves the compression from the nerve.
Another shoulder issue is called long thoracic nerve palsy, which comes from the C5, C6, and C7 area. The nerve passes the brachial plexus, a group of nerves that come from the neck and branch off to feed out to most of the nerves that control movement in your arm. The purpose of this nerve is to move the scapula, the bone at the back of your shoulder, as necessary.
If this area has become injured, it's usually because of a blunt trauma to the area or if your neck is turned, with your head facing the other direction away and the shoulder is forced back in the opposite direction. Signs of this injury are usually pain underneath the scapula, difficulty raising the arm, and a popping or clicking sound coming from the scapula region when you try to lift your arm. The majority of patients recover without surgery, although it can take as long as two years for full recovery. To do this, the activity of the arm and shoulder must be limited for a while and exercises are important to maintain arm strength. If the problem isn't resolved after a year, then surgery is usually the next choice.
Quadrilateral space syndrome is a condition where a nerve that comes up from behind the brachial plexus and provides sensation to the deltoid muscle and surrounding area is damaged. The deltoid is the muscle around the shoulder itself. If there is damage in that part, patients may complain of shoulder discomfort, not necessarily outright pain, especially when the shoulder is forward, with the arm raised. This injury is often found in adults between the ages of 20 ad 35 years and usually on the dominant hand.
Treatment for quadrilateral space syndrome is usually rest for the shoulder, anti-inflammatory medications to reduce any swelling and relieve pain, cortisone injections into the area, and physiotherapy. If, after six months, there is no improvement or not enough improvement, surgery may be the next step.
Finally, the last injury covered in this article is the thoracic outlet syndrome, which occurs in the area bordered by the first rib and the collarbone. If a patient has this problem, the signs are usually neck or shoulder pain and weakness of the arm on the hurt side. If the artery is being pressed upon, the arm may be painful and discolored, with it becoming pale after exercise. Rarely, a patient could have a stroke.
To diagnose this problem, doctors do a neurological (nerve) examination and see if they can reproduce the symptoms with certain techniques. X-rays are done to rule out other problems, as is an angiogram to see if there is any blockage in the artery. As with the other shoulder injuries, first treatment is conservative, to try to avoid the need for surgery. This means physiotherapy to improve the arm strength and body posture. This type of injury may require several months of treatment before any improvement is seen. However, if the treatment fails or there is a progressive worsening of symptoms, surgery may be done.
The authors of this study concluded that the various shoulder nerve syndromes can be quite similar in symptoms and in treatment, with surgery being the back up approach if conservative treatment is not effective.
Jason A. Freedman and James A. Shankwiler. Nerve compression syndromes about the shoulder girdle. In Current Orthopedic Practice. September/October 2008. Vol. 19. No. 5. Pp.
