It’s coming up to flu season again and by all accounts it’s an early season. You may be due for your COVID vaccine or the flu shot. I myself get a flu shot every year, working in healthcare and having had the flu before are both reasons I choose to have an injection. With the advent of vaccinations in the 18th century due to the work of Edward Jenner and the smallpox vaccine, we are not unfamiliar with having vaccinations for ourselves and our children. Our own children have had their vaccinations from an early age without incident including MMR (measles, mumps, rubella) and Varicella (Chicken pox) to name a few.  How these injections are given are intramuscular, meaning that it is given into the muscle, in my case when I had my flu shot this week it was into the deltoid muscle of the shoulder.

Sore shoulder post injection is nothing new, I myself will have a sore shoulder every time without fail, but is there a correlation between conditions such as Frozen Shoulder and injections?

Yes it is very normal to have a reaction to an injection and the Department of Health NSW or your GP can advise you on what to expect and what is considered normal and what is not. Having had multiple COVID and Flu injections, I can say that my shoulder was quite sore, and it bothered me for a few days, but this didn’t last. 

So what is Frozen Shoulder? Sometimes misdiagnosed, Frozen Shoulder or what we call Adhesive Capsulitis, presents initially as a painful shoulder and later becomes stiff with movement resulting in muscle weakness due to underuse, problems with engaging in activities of daily living such as getting dressed, washing your hair, brushing your teeth and so on. In time, we see spontaneous complete or nearly-complete recovery over a period of time which can be up to two years in some cases, three at worst.

How is Frozen Shoulder different to a sore shoulder? We know what some of the predisposing factors of Frozen Shoulder are, such as being female, over a certain age, co-morbidities such as metabolic disease, post operatively after shoulder surgery/mastectomy or after a traumatic event involving the upper limb. However, we still don’t know exactly why it occurs, and thus it is known as idiopathic, of unknown origin. And while we have seen patients present with longer than usual shoulder pain and stiffening post injection, we can happily say that this didn’t last. Does this mean it was Frozen Shoulder in the first place? We can’t say this, as the COVID vaccine is relatively new and the pandemic situation and the health response will change over the years to come. We are forever learning about our bodies, doing research and developments in the health sector will continue which just goes to show how flexible and innovative it is. 

Hence, a sore arm after a COVID jab or flu vaccine is expected, however, this shouldn’t continue and if you aren’t sure get this checked.  

Many thanks
Sam and Andy