Some shoulder pain builds gradually over months.
This one can take you from functional to barely able to move your arm within a couple of days, with pain severe enough that people present to A&E convinced something has torn.
And the counterintuitive part is that the most agonising phase is the point at which the problem is resolving.
The condition is calcific tendinopathy, and understanding what is happening changes how the whole episode feels.
What It Is
Deposits of calcium hydroxyapatite crystals form within the rotator cuff tendons.
It is distinct from the degenerative tendon problems people usually mean by tendinopathy. Reviews describe it as affecting otherwise healthy tendon, with crystals depositing between healthy tendon cells, rather than being a wear related process.
It is common. It has been reported as accounting for somewhere between 10 and 42 per cent of all shoulder pain, with prevalence figures of up to 42.5 per cent in people presenting with shoulder pain.
And it is frequently silent. In a study of 304 asymptomatic female volunteers, 24 per cent had calcific deposits visible on shoulder ultrasound, with another study reporting a prevalence of 17 to 31 per cent in asymptomatic women. Up to 20 per cent of people with deposits may have no symptoms at all.
Which means a deposit on your scan does not automatically explain your pain, and that is worth knowing before anybody rushes to treat the image.
The Phases
This is where the counterintuitive part comes in, and it is the most useful thing in this article.
The condition progresses through recognised phases.
A formative phase, where calcium is deposited. Associated with mild pain, or none.
A resting phase, where the deposit sits unchanged. Frequently asymptomatic or mildly uncomfortable.
And a resorptive phase, where the body breaks the deposit down and clears it away.
Severe pain correlates with the resorptive phase.
The mechanism is the clearing process itself. The resorptive phase is characterised by new blood vessels growing into the area and immune cells arriving to break down and remove the deposit. That inflammatory activity is what produces the pain.
So the agony is the body dissolving the problem.
Which is genuinely useful information when you are in it, because the natural interpretation of sudden severe shoulder pain is that something has gone badly wrong, and in this case the opposite is closer to the truth.
How It Shows on Imaging
The appearance on X ray corresponds to the phase, which clinicians use.
A dense, well defined deposit typically indicates the formative or resting phase, and people with this appearance often have mild pain or none.
A fluffy, ill defined deposit with an unclear border corresponds to the resorptive phase, which is the acutely painful one.
So the deposit that looks less impressive on the image is frequently the one causing the severe pain, which is another reason the scan needs interpreting alongside the clinical picture rather than on its own.
It Is Self Limiting
Reviews consistently describe calcific tendinopathy as a self limiting condition.
Which means the deposits are cleared and the episode resolves, given time.
The difficulty is the time, and the severity of the acute phase, which can be functionally disabling for weeks.
Which is why treatment exists. Not because the condition will not resolve, but because the clinical course can be accelerated and the pain is frequently intolerable.
What the Treatments Are
For most people, the first line is conservative. Pain management, activity modification, and physiotherapy, with the acute phase managed as comfortably as possible.
If that is insufficient, two interventions have the best supporting evidence.
Ultrasound guided needling and lavage, also called barbotage. A needle is placed into the deposit under ultrasound guidance, the deposit is broken up, and fragments are washed out.
One evidence based review described ultrasound guided percutaneous lavage as currently the most efficacious and most frequently used treatment for shoulder calcific tendinopathy, on the basis that it effectively reduces both calcium burden and pain while limiting damage to surrounding tissue.
Good candidates are described as those with at least one large deposit, and it is noted that the procedure frequently produces adequate pain relief and functional improvement even when the calcium cannot be fully aspirated.
Extracorporeal shockwave therapy is the other option with supporting evidence.
A systematic review found moderate evidence for the benefit of high energy shockwave therapy over low energy shockwave therapy, and moderate evidence for the benefit of ultrasound guided needling.
Both barbotage and shockwave therapy have been shown to reduce calcific deposits with significant pain reduction and functional improvement.
There are no head to head comparisons between them, which is worth knowing if you are offered one or the other.
Corticosteroid injection may be used for symptom control, and surgical removal exists for cases not responding to the above.
The Honest Caveat
The overall evidence for management of this condition is described as low quality, with current recommendations based on limited clinical data.
Which does not mean the treatments do not work. It means the certainty is lower than you would ideally want, and that is worth knowing when weighing an intervention against waiting.
What to Do If You Are in the Acute Phase
Pain relief, discussed with your GP or pharmacist, since this phase can be genuinely severe.
Ice, which many people find helpful during the inflammatory phase.
Keep the shoulder moving within comfort, gently, rather than immobilising it completely. Prolonged immobility risks stiffness, and frozen shoulder developing on top of this is a recognised complication worth avoiding.
Avoid aggressive stretching or loading during the acute phase. This is not the moment for a strengthening programme.
And get it imaged if the diagnosis is uncertain, since a plain X ray will usually show the deposit and distinguish this from other causes of acute shoulder pain.
Then, once the acute phase settles, rehabilitation to restore range and rebuild strength, which is where the longer term outcome is determined.
Symptoms That Need Prompt Assessment
See your GP promptly for:
Severe shoulder pain of sudden onset, particularly with marked loss of movement.
Inability to use the arm.
True weakness rather than pain limited movement.
Numbness or tingling down the arm.
Fever alongside a hot, acutely painful shoulder, which needs same day assessment since joint infection is a different and urgent problem.
Any history of cancer with new shoulder pain.
And seek emergency care for shoulder or arm pain accompanied by chest discomfort or pressure, breathlessness, sweating, nausea, or pain spreading into the jaw.
Get It Identified Properly
Acute severe shoulder pain has several possible causes, and this one has a specific appearance, a specific course and specific treatment options.
Body Zest offers a free discovery visit at no cost and no obligation. You will get a thorough assessment, a clear explanation of what you are dealing with and where you are in the course, and a plan for both the acute phase and the rehabilitation that follows.
If your presentation suggests imaging or referral for a procedure is warranted, we will tell you plainly.