Frozen Shoulder Treatment
Frozen Shoulder affects 2% of the population at some time in their life. In people with diabetes, up to 20% may develop Frozen Shoulder.
Frozen Shoulder is a condition that may occur spontaneously without apparent cause, or it may come on after an injury or surgery to the shoulder. The disease starts as an inflammation of the capsule of the shoulder. All joints in your body have a joint capsule. The capsule is a flexible thin membrane that lines the shoulder joint. This inflammation is painful, and patients often experience severe aching pain, which can keep them awake at night. The shoulder may be diagnosed as suffering from impingement because, at this early stage in the disease process, the two conditions appear very similar.
After some months of the capsule being inflamed, the shoulder becomes stiff. The stiffness occurs as the capsule thickens and becomes fibrotic as a response to the inflammation of the capsule. At this point, the joint is painful and stiff, which is particularly unpleasant. Eventually, the condition resolves entirely of its own accord. However, it may take one to two years to resolve, sometimes longer.
Due to the common relationship with diabetes, I recommend to patients that if they have Frozen Shoulder or think you might, it is advisable that they ask their GP about testing for diabetes. A simple, fasting blood glucose test is usually adequate.
The cause of Frozen Shoulder is unknown, and as such, there is no treatment available to cure Frozen Shoulder. Instead, treatment is aimed at dealing with the symptoms. The main symptoms of Frozen Shoulder are pain and stiffness.
The pain of Frozen Shoulder is due to the inflammation of the shoulder joint capsule and tends to be exacerbated by movements that stretch the capsule. For the pain, a cortisone injection placed into the shoulder joint (the glenohumeral joint, not the bursa) can be beneficial in settling down the inflammation and helping ease the pain and discomfort. The injection contains cortisone and local anaesthetic. The local anaesthetic will ease the shoulder pain for the first few hours after the administration of the dose. This initial relief of the shoulder pain due to the local anaesthetic gives further evidence to support the diagnosis of your shoulder condition being a Frozen Shoulder.
The cortisone works by acting as an anti-inflammatory, helping to resolve the capsulitis that occurs at the beginning of the frozen shoulder condition. Cortisone is a true anti-inflammatory with potent efficacy as compared to the more commonly known anti-inflammatory tablets that we take, such as aspirin or, which have only a weak anti-inflammatory effect. The cortisone used is usually betamethasone (a fluorinated cortisone molecule) which is a powerful steroid medication. It is also available in tablet form and if taken for some time frequently induces complications such as weakening of the bones, increased susceptibility to infection and weight gain, among other issues. It usually takes at least several weeks taking these cortisone tablets for these complications to develop. A single cortisone injection into the shoulder joint has a similar dose to a daily cortisone dose taken in tablet form and is unlikely to induce the complications seen with taking the tablet forms over several weeks. Usually, I recommend a single cortisone and local anaesthetic injection into the shoulder joint to start with. Occasionally, patients require more than one injection. However, I don’t recommend more than three cortisone injections into the same location in the shoulder, and I recommend that the injections are given at least a month apart. Injections into the shoulder joint can introduce bacteria from the skin into the shoulder and in rare cases, infections have occurred following an injection.
There is some evidence suggesting that a cortisone injection into the shoulder joint (the glenohumeral joint) not only greatly helps with the aching pain of frozen Shoulder but that it reduces the length of time it takes for the condition to resolves. The injection helps shorten the time that Frozen Shoulder takes to get better. Hazleman and coauthors reported in the journal Rheumatology and Physical Medicine in 1972 that patients who receive the injection earlier in the course of the disease recovered more quickly. Dias and coauthors wrote in 2005 in the British Medical Journal (BMJ) that early treatment with a steroid injection into the intra-articular GH joint may reduce synovitis, thus shortening the natural history of the disease.
Sun and coauthors published a systematic review and meta-analysis of 8 randomised controlled trials, totalling 416 patients, in 2016 in the American Journal of Sports Medicine. They concluded that pain scores and passive range of motion were improved in the first 16 weeks and that the effects of a cortisone injection may last as long as 26 weeks.
I don’t recommend that patients undergo hydrodilatation when they have a cortisone injection to the glenohumeral joint for Frozen Shoulder. Hydrodilatation is where the local anaesthetic and cortisone is forcibly injected into the shoulder joint in an effort to stretch the shoulder capsule. There is very little evidence to support giving a cortisone injection with hydrodilatation over administering a cortisone injection on its own. Hydrodilatation is typically painful and, in my experience, too often aggravates the condition.
The stiffness in the affected Shoulder is due to significant thickening, fibrosis and contracture that occurs in the shoulder capsule. The capsule is usually a thin pliable membrane. As the capsule becomes fibrous and contracts the ball of the shoulder joint (the humeral head) becomes tightly held and unable to move in the socket of the shoulder joint (the glenoid) severely restricting the range of motion of the Shoulder. The stiffness eventually resolves in all patients with Frozen Shoulder. Consequently, the initial recommendation to most patients is to allow it to resolve with time.