Sub-Acromial Shoulder Pain: A Well Overdue Update

The State of Play

Shoulder pain is the third most common musculoskeletal condition after neck and back pain. What is worrying is that around 40 to 50 percent of new shoulder pain presentations continue to have symptoms six to twelve months after the initial onset. You can almost flip a coin to predict whether someone will develop a chronic shoulder condition.

A study by Imagama and colleagues in 2019 found that shoulder pain had a greater impact on both physical and mental quality of life than knee and lower back pain.

How has it come to this?

Words Matter

If you have ever experienced non traumatic shoulder pain at the front or outside of the shoulder and sought help from a physio, GP, or specialist, you may have been given information that unintentionally did more harm than good.

Many people are still told that their pain is caused by “impingement” of the tendons or bursa between the bony structures of the shoulder blade and the upper part of the socket.

This idea was introduced more than fifty years ago by Neer, an orthopaedic surgeon who believed that most rotator cuff tears came from impingement. This led to the rise of sub acromial decompression surgery, which we now know is no better than placebo surgery according to a Cochrane review from 2019.

Explaining shoulder pain using structural or impingement language can create fear, low confidence, and negative expectations. This can reduce a person’s belief that physiotherapy will help and can become a barrier to recovery.

I used the term “impingement” earlier in my career before strong research emerged to challenge it. Research takes time to become common practice, but with so many people experiencing chronic shoulder issues, it is time to change the narrative.

A Good Plan to Scan?

GPs in Australia are referring patients with shoulder pain for imaging at rapidly increasing rates. Imaging referrals have risen from 20 percent in the year 2000 to around 55 percent today. So, how useful are scans?

Several studies have followed people ten to sixteen years after a rotator cuff repair. Between 37 and 50 percent had re ruptured their repair on imaging, yet their shoulder function was no different from those with an intact repair. This challenges the idea that structure alone determines outcome.

Another study looked at ultrasound findings in people without shoulder symptoms. Ninety six percent had “abnormalities” such as bursitis, rotator cuff tendinosis, or AC joint osteoarthritis.

In young American college baseballers with no pain, imaging showed articular sided rotator cuff tears in 47 percent of players, yet they could still throw at 150 kilometres per hour.

Imaging findings can influence expectations in the same way structural language does. Thankfully, there is strong evidence supporting a wait and see approach before imaging, especially for gradual onset shoulder pain. It reinforces the importance of treating the person, not the scan.

Have a go at an Injection?

https://www.kinimaphysio.com.au/blog/corticosteroid-injections

The rate of corticosteroid injections for shoulder pain has also increased in Australia, rising from 10 percent to 20 percent over the last two decades.

A recent review looking at short and long term effects of corticosteroid use for rotator cuff related pain found possible short term benefit but no long term benefit. Interestingly, the same review found evidence of long term harm in other joints including the knee, elbow, and hip.

Studies comparing corticosteroid injections with active rehabilitation found:

• Injections were more effective in the first six weeks

• At twelve weeks, injections were equal or worse than exercise

• From six months onward, active rehabilitation was more beneficial

This evidence suggests injections should be used sparingly and not as a first line treatment for non traumatic shoulder pain. There is a time and place for injections, but the bar should be set higher. 

A New Dawn

Despite increasing referrals for imaging and injections, only about 12 percent of non traumatic shoulder pain cases are referred to physiotherapy. This is well below best practice guidelines.

So, what does best practice management look like?

1. Change the Label

Move away from old terminology and use sub acromial shoulder pain or rotator cuff related shoulder pain.

2. Change the Explanation

Shoulder pain develops when the individual does not have the capacity to tolerate the load placed on the shoulder over time. Capacity is multi dimensional and includes physical, psychological, emotional, behavioural, genetic, and lifestyle factors.

3. Avoid Unnecessary Interventions

If the pain was not caused by trauma, allow time for symptoms to turn the corner with load modification and a graded approach to exercise.

4. Screen for Key Factors

Low expectations, poor self efficacy, and fear of movement can strongly influence recovery.

5. Use Person Centred Goal Setting

Goals should reflect what the individual actually needs, values, and wants to return to.

6. Follow Evidence Based Management

This includes education, load management, a structured strengthening program for the shoulder and surrounding regions, and a clear plan for returning to function or sport. These programs are most effective when completed for three to twelve months.

If you would like to learn more about current evidence based approaches to shoulder pain, our team is here to help.