Do I need an injection?
Injections for musculoskeletal (MSK) disorders like arthritis of the knee, frozen shoulder and tenosynovitis are a common form of treatment used by physiotherapists and doctors. For many years the only injection option was cortisone injections – but over the past decade or so other types of injections have become available and this can make it confusing for patients. So let’s have a look at the pros and cons so you can consider whether you need an injection at all.
First things first. The decision about whether you need an injection is needed is based on many factors:
- the cause and severity of the pain
- whether other treatments can help
- the stage of the condition
- whether there are any contraindications
- most importantly, the patient’s preference
If your physio thinks an injection would help, they will discuss this with you and then it’s up to you.
So what are the different types of injection?
Cortisone
When can this be used?
Its primary use is anti-inflammatory so in conditions where there is clear evidence of inflammation like a very painful arthritis or tenosynovitis it is the ‘go to’ treatment because it is so effective. The thing that clinicians have to weigh up though is the downside of cortisone because it is possible to create a spectacular improvement in the short-term which is lost once its effects wear off. As physios we try and limit this outcome by advising on careful activity and loading in the weeks after injection. For conditions like tenosynovitis and bursitis where injury has led to pain developing, an injection of cortisone can be curative.
What conditions respond to cortisone injections?
Frozen shoulder, shoulder arthritis, shoulder bursitis, acromioclavicular injury, elbow joint arthritis, biceps bursitis, thumb joint arthritis, carpal tunnel syndrome, trigger finger, de Quervain’s tenosynovitis, hip arthritis, trochanteric bursitis, knee arthritis, ankle arthritis, heel bursitis, big toe arthritis and Morton’s neuroma.
Pros
✅ Known to have strong anti-inflammatory effects which help to reduce pain
✅ Usually create benefit within 3 days
✅ Can achieve a big improvement quickly
Cons
❌ Benefit sometimes short lived (2-6 weeks)
❌ Cannot be repeated frequently
❌ Is avoided for tendon problems if possible
❌ Can cause damage to the tissues if repeated too frequently (we recommend no more than 2/year)
❌ Can cause damage to soft tissues (e.g. tendons)
❌ Also has immunosuppressive properties that can be associated with slight increase risk of infection post-injection
Hyaluronic Acid
When can this be used?
Hyaluronic Acid or HA is a molecule naturally proved by the body and its role in synovial joints is to provide viscoelastic properties that help to facilitate movement and absorb load. It also covers the joint surfaces and provides a barrier to inflammatory mediators which can cause pain and stiffness developing in the joint. We know that the HA degrades in an arthritic joint which reduces its ability to protect the joint and keep it working optimally. Injecting synthetic HA helps to restore more normal conditions within the joint and resist the deleterious changes caused by arthritis. It is usually reserved for joints that are less inflamed but where ‘wear and tear’ is still evident. Sometimes HA and cortisone are combined to obtain the shorter term improvement of cortisone and the longer lasting benefits of HA.
What conditions respond to HA injections?
Shoulder arthritis, acromioclavicular arthritis, elbow arthritis, thumb arthritis, hip arthritis, knee arthritis, ankle arthritis, big toe arthritis.
Pros
✅ No known side effects
✅ Restores lubrication and shock absorption properties of the joint
✅ Commonly used in sports medicine
✅ Longer lasting effect
✅ No limit to repeated injections
✅ Offers a viable alternative to surgery
Cons
❌ Improvement tends to be more gradual
❌ Sometimes needs to be combined with cortisone or PRP to achieve maximum benefit
Platelet rich plasma (PRP)
When can this be used?
PRP is a new technology that has been pioneered in the world of sport and has been found to be an effective treatment for people with arthritis and tendon problems like Achilles tendinitis and Tennis elbow (which can prove difficult to treat with cortisone). It is part of the new area of regenerative medicine that is involved with the process of replacing, engineering or regenerating human or animal cells, tissues or organs to restore or establish normal function by stimulating the body’s own repair mechanisms to functionally heal previously irreparable tissues. Where cortisone injections have failed to achieve a satisfactory outcome or where these have been avoided, PRP provides an excellent natural alternative.
For joint conditions like arthritis, we combine PRP with hyaluronic acid – called Cellular Matrix injections. The is a growing body of evidence that shows a superior outcome when combining the regenerative potential of PRP with the viscoelastic properties of HA. Combined PRP + HA is considered ‘gold standard’ treatment for joint problems affecting the knee particularly.
What conditions respond to PRP injections?
Knee arthritis, rotator cuff problems of the shoulder, tennis elbow, golfers elbow, Achilles tendinopathy, plantar fasciitis.
Pros
✅ Completely natural option (uses your own blood)
✅ Aims to regenerate the condition as opposed to managing the symptoms
✅ Longer lasting improvement
✅ Strong and growing evidence base
✅ Used widely in professional sport
✅ Effective treatment for recalcitrant tendon and muscle injuries
Cons
❌ Involves a sequence of 3 injections repeated at 2-4 week intervals
❌ Requires a blood sample to be taken for each injection
❌ Most costly option
So do YOU need an injection?
The reasoning around whether an injection is appropriate is a complex decision that we’ve spent the last 20 years refining so if you’re none the wiser then don’t worry – that is why we’re here! The best thing you can do is make arrangements to see us where we will thoroughly assess your condition and give you our opinion on the best way forward. There are many treatment options available and injection therapy is a small part of what we do here.
