Frozen shoulder, also known as adhesive capsulitis, is one of the most common shoulder problems I see in clinical practice. It is estimated to affect 2% – 5% of the general population, and 20% of patients with diabetes.
Patients present with pain and progressive stiffness of the shoulder, and are often middle aged or elderly. It is highly unusual to see frozen shoulder in young patients.
In fact, the mandarin colloquial term for frozen shoulder is “wu shi jian” which literally translates to “50 year-old shoulder”! Some basic knowledge of the anatomy of the shoulder will help with understanding the problem of frozen shoulder.
Anatomy of the Shoulder Joint
The shoulder joint is made up of 3 bones: the shoulder blade (scapula), the humeral head and the collar-bone (clavicle).
Movements around the shoulder involve 3 separate articulations: the glenohumeral joint, the acromioclavicular joint and the scapulothoracic articulation. When the arm is raised, the majority of movement occur at the glenohumeral joint and the scapulothoracic articulation.
The glenohumeral joint is a ball and socket joint, comprising the socket (the glenoid) and the ball (the humeral head). Both surfaces of the joint are covered with an extremely smooth and rubbery cartilage (known as articular cartilage).
The smooth surfaces create a frictionless articulation when lubricated with a small amount of joint fluid. The glenohumeral joint is housed within a strong covering known as the capsule. The capsule keeps the joint separate from the surrounding tissues like muscles.
In normal, healthy shoulders, the capsule has a pale pearly appearance, and is rather thin (1-2mm perhaps).
What symptoms might I experience if I have frozen shoulder?
The 2 most common symptoms that patients experience are pain and stiffness of the shoulder. The pain is typically felt on the arm, underneath the deltoid muscle.
This is often surprising to the patient and I have had many patients query me as to why I think they have a shoulder issue when their problem is that of a painful arm! Often the pain starts insidiously without any obvious inciting event.
Others may report an often mild and somewhat insignificant “injury” like having a slight jerk while taking the train or feeling a mild twinge of discomfort while reaching out for something. The pain then slowly becomes more noticeable over the course of a few weeks to months.
The intensity of pain may vary between different patients. In some patients, the pain is mild and is more of a niggling irritating discomfort. But in some patients, the pain may be severe and interfere with activities of daily living.
Many patients report having pain at night which often prevents them from sleeping, or wakes them up from sleep. Side sleepers have more difficulty with sleeping because they feel pain if they sleep on the affected side, but when they lie on the other side, the arm of the affected side falls across the body and this causes pain as well!
Many patients also experience stiffness of their shoulders. The most severely affected movement is often internal rotation. Many male patients will report that they are unable to place their wallets in the back pocket of their pants while ladies will find that they are unable to reach behind their backs to clasp their bra.
Many patients will also experience weakness of their arms but this is often due to pain when trying to lift loads or trying to move beyond the range possible for their stiff shoulders.
What will the doctor do?
Your doctor will chat with you and ask you more about the. A careful examination of the shoulder is then carried out. He (I will use “he” to refer to the doctor to simplify the discussion although clearly, there are many female doctors out there!) will need to visually inspect your shoulders, looking out for any asymmetry or wasting of the muscles.
He then feels around the shoulder looking for any tender spots which may give a clue as to the source of the problem. This may be particularly hard in large or muscular patients.
He then tests your shoulder movements. The range of movements in patients with frozen shoulders often depends on how long he/she has been having the condition.
In early cases, patients may have close to full range of movement. However, in patients a few months into the condition, they may have globally reduced movements (i.e. movements of the shoulder are reduced in all angles).
By this time, your doctor should be reasonably sure of his diagnosis of a frozen shoulder. The only other condition that may closely mimic a frozen shoulder is that of shoulder arthritis. This is a condition where the cartilage of the glenohumeral joint is worn out.
Please see the section on shoulder arthritis if you would like to learn more.
What tests can be done to confirm the diagnosis?
Many doctors may begin their investigations with x-rays for the shoulder. In frozen shoulders, however, X-rays are often completely normal. Having said that, I often do proceed with either x-rays or more detailed scans to ensure that I am not dealing with shoulder arthritis or other superimposed problems like a rotator cuff tear, for example.
An MRI (magnetic resonance imaging) scan may be useful in frozen shoulders, but it is not necessary for diagnosis. I mainly perform MRI scans in patients only if I am unsure if there might be a rotator cuff problem or if his/her symptoms and presentation is unusual.
I am told I have frozen shoulder. What is a frozen shoulder?
Frozen shoulder is a condition in which the capsule of the joint becomes inflamed, thickened and stiff, hence severely restricting movements of the joint.
There are 2 types of frozen shoulders: primary and secondary. In primary frozen shoulder, there is no cause for the condition (i.e. idiopathic), whereas in secondary frozen shoulder, the stiffness has occurred as a result of an injury (e.g. a fracture near the shoulder joint, a torn rotator cuff, infection of the shoulder joint etc), or more commonly, systemic illness like diabetes, thyroid disorders, heart problems etc.
Frozen shoulders often follow 3 phases. Each phase may last for 3 – 6 months. The first phase is called the freezing (or pre-adhesive) phase.
Most patients who present at this phase come because of pain. Movements in their shoulders are often still very good. The second phase if is called the frozen (of adhesive) phase.
During this phase, pain in the shoulder is often reduced, but the shoulder gets increasingly stiff (hence the term “frozen”). The third and last phase is called the thawing (or recovery) phase. During this phase, pain is further reduced and movements start to recover.
How can a frozen shoulder be treated?
Treatment of frozen shoulders depend on the phase at which the patients present. Generally, treatment comprises pain relief and physiotherapy.
If the patient is still in the first phase (freezing phase), pain is usually the main symptoms and movements of the shoulder are still good. For such patients, medications for pain can be helpful in alleviating the pain.
However, if the pain is severe and affects the patient’s activities of daily living or sleep, a steroid injection administered into the shoulder joint can significantly reduce the pain. Physiotherapy modalities will be mainly techniques aimed at reducing pain.
If the patient is has already progressed to the second phase (frozen phase), restriction of movement as well as some pain may be present. Treatment is hence directed at relieving the pain (via medications and a steroid injection) as well as maintaining and restoring range of movement in the shoulder.
Most frozen shoulders will resolve with time and noninvasive treatment modalities as described above. However, not all do. For cases that fail to improve, invasive treatment options may be required.
What kind of invasive treatments are there?
Hydrodilatation is a procedure during which a needle is introduced into the shoulder joint, under some form of image guidance (usually using x-rays), and a large volume of saline and local anaesthetic is injected forcefully to distend or even rupture the capsule of the shoulder joint.
Scientific evidence of the efficacy of this procedure is fairly good in terms of improvement in movement in the shoulder. However, this is not a procedure I often prescribe. The main reason is that this procedure can be very painful for the patient and that severely limits the amount of dilatation that can be achieved.
Manipulation under anaesthesia (MUA):
This is a procedure that is done under general anaesthesia. The patient is anaesthetized and the surgeon forces the shoulder into full movements by forcefully manipulating it and tearing the joint capsule.
I never perform this procedure by itself due to the very real risk of causing a much bigger complication. I have seen patients end up with broken arms and shoulder dislocations after having these procedures done, even by experienced and senior surgeons.
The risk is even higher if the patient is thin and petite, and breaking such patients’ arms is actually much easier than you might imagine! The last thing I want is for a patient to go to sleep (under anaesthesia) with a frozen shoulder and wake up with a broken arm which will likely require a different surgery to fix!
Arthroscopic capsular release (ACR):
This is the procedure I usually perform in patients whose frozen shoulder does not improve despite having done physiotherapy for a fair amount of time (perhaps a few months).
Some other patients may not have the patience (no pun intended!) to wait out the natural course of the condition and may prefer a good way to “short-circuit” the recovery.
In an ACR procedure, the patient is put under general anaesthesia and just 2 small incisions are made (one at the front and one at the back of the shoulder). These incisions just need to be 4mm long. This will permit me to insert a camera into the shoulder joint and divide the thickened capsule under direct vision.
As the surgery is done under direct vision, the procedure is very safe. At the end of the procedure, I then gently manipulate the shoulder to get optimal movements out of the shoulder. This manipulation is very gentle and very little force is required, hence eliminating the risk of causing fractures or dislocations.
The pain relief after the procedure is usually very satisfactory. Though conceptually easy, this surgery can be rather tricky sometimes due to the very small space in the shoulder joint resulting from the frozen shoulder.
As such, if the surgeon is not suitably experienced, attempts to perform this procedure may result in scuffing and damage to the smooth articular surfaces of the shoulder joint. So, do ensure your surgeon is experienced with shoulder surgery and you will be most happy with the results!
What should I do now?
If you have managed to get to this part of this long article, your shoulder must be bothering you significantly! Consult your family doctor or see an orthopaedic specialist and he/she should be able to advise you accordingly.