What is causing my shoulder pain?

Chances are if you are over 40 years of age that it is rotator cuff tendinopathy, a rotator cuff tear, acromio-clavicular osteoarthritis or a frozen shoulder.
In fact it could be a combination of any of the above.

Rotator cuff problems are very common. They start with pain in the upper arm and the top of the shoulder. Typically there is catching pain on reaching behind for something like in the car. There can be darts of pain and also dull aching. The dull ache is typically worse at night and can prevent sleep. It seems to be worse on lying down. It can settle for no particular reason after a few months. Perhaps physiotherapy can help this or it eases itself with time anyhow.
We used to think that this was a mechanical problem of the rotator cuff rubbing off the acromion bone and ligament on abduction but it is probably more complex than this. With the normal aging process there is breakdown of the fibres of the cuff. There is degeneration of the tendons and this sets up a repair / breakdown cycle. Pain chemicals are also involved.

If the pain persists for 2 months or so it will be worthwhile getting a MRI scan to assess the situation. The MRI will show the condition of the rotator cuff tendons and tell if there is an actual tear in the tendon. This is commonly in the anterior part of the supraspinatus tendon. It can occur with the normal aging process and can also be helped on its way by a fall which will cause a sudden failure of the tendon.
A tear of the rotator cuff may be a common finding in MRI of the shoulder and is seen in 50% of patients aged 60 years. If it is associated with pain I feel that a rotator cuff repair is a good operation for pain relief. In over 80% of cases the pain in the shoulder caused by a rotator cuff tear can be relieved by rotator cuff repair.

If there is no rotator cuff tear then there are simpler options available. Typical impingement pain may be a sign of a failing tendon that will go on to tear. An injection of steroid in the sub acromial space is certainly worth a try and can have a dramatic effect in about 50% of patients. A second injection can be used if the first one had a good effect. There are concerns about injecting of steroids. My opinion is that there is no hard evidence on how many injections can be given. I would usually stop at 2 and then move on to another treatment option but if the patient really did not want to go on to surgery then there is no reason not to have 5 or 6 injections or more. I am reluctant to give steroid injections to people who are involved in heavy work as I have seen that with the pain relief from the injections patients can go on to rupture their tendons from aggressive manual work. However if I have discussed this possible complication and the patient is going to take it easy I see no reason not to use this useful treatment.

For those that do not improve with injections then surgery to trim the acromion and decompress the sub acromial space is a good option. I find the pain relief after this procedure to be somewhat variable and may be not as good as in rotator cuff tears strangely. Some patients get a dramatic improvement and some others continue having pain. However it is certainly worthwhile persevering with rehab and giving the shoulder at least a year to settle after this surgery.

Rotator cuff surgery and sub acromial space surgery can often be combined with resection of the acromio clavicular joint. This joint when arthritic causes pain around the joint itself and also to the side of the neck. It can also cause impingement type pain. It can be resected arthroscopically by removing 1cm of the clavicle. The space then fills up with scar tissue and this prevents the arthritic bones from rubbing together.

A frozen shoulder is just that and I prefer this term to adhesive capsulitis as I am not sure if there is an inflammatory process involved. Usually for no reason the capsule of the shoulder joint becomes fibrotic, thick and stiff. The typical shoulder is frozen and there is very little movement with a solid end feel and no give in it. The patient could wait 1 to 2 years for it to thaw out or have arthroscopic surgery. I prefer to release the capsule arthroscopically as I believe that this cuts and releases the thickened capsule. With a manipulation, I see with the arthroscope that the capsule does not tear but it pulls the labrum with some bone from the glenoid off the glenoid itself and this is how movement is achieved. It is for this reason I prefer to see that it is the actual capsule that is cut by doing the procedure arthroscopically.
There may not be a dramatic improvement in movement but it starts the process of rehabilitation. Gradually the pain levels decrease and the movement increases. I find arthroscopic capsular release a good treatment option in a frozen shoulder.

Shoulder pain is usually caused by rotator cuff problems, acromioclavicular osteoarthritis and a frozen shoulder in middle aged patients.

In my next blog I will discuss shoulder problems in the younger age groups where there is a somewhat different spectrum of pathologies.