Ultrasound guided subacromial bursa steroid injection

What is sub-acromial bursitis?

What are the causes of shoulder bursitis?

What is sub-acromial bursitis?

Trochanteric bursitis is among our practice's most common indications for ultrasound-guided steroid injections. The condition is characterised by a pain sensation on the outside of the hip. The pain is usually located next to a bony prominence at the outer aspect of the hip (called the greater trochanter), hence the condition's name. It is usually caused by inflammation of the gluteal tendons, a special group of tendons that attach to the greater trochanter. Therefore, the condition is sometimes referred to as “gluteal tendonitis”. Another name for this condition is “trochanteric bursitis”. This refers to the inflammation of a fluid-filled sac that lies on top of the tendons (called the trochanteric bursa).

What are the causes of shoulder bursitis?

Shoulder bursitis is more common in people over 40 but can be seen in younger people. It can happen gradually over time due to increased stress upon the bursa or a sudden increase in activity (like starting a new sport). Bursitis can also be seen after injury.

The bursa produces more fluid in bursitis, and the bursa's wall becomes thicker. This will result in pain and continuous irritation of the bursa during shoulder movement. In addition, when the bursa is inflamed and thickened, the underlying rotator cuff tendons might get pinched, affecting their movement and function. The tendons, in turn, can get inflamed (tendinosis). The whole process is referred to as shoulder impingement and may cause a vicious circle of bursitis and tendon inflammation. If the pain continues for over three months, the condition might be called “chronic shoulder bursitis”.

subacromial bursitis ultrasound guided steroid injection

What conditions are associated with Shoulder bursitis?

Shoulder bursitis is commonly associated with problems of the rotator cuff tendons, given their close anatomical and functional relation, and both can be associated with shoulder impingement.

The most common conditions associated with bursitis are:

Rotator cuff tendon pain: Due to inflammation or tear of the tendons.
Calcific tendonitis: Due to irritation of the bursa by the calcium deposit within the rotator cuff tendons.
Acromioclavicular (AC joint) problems. This would include previous injury or arthritis of the AC joint, which can predispose to shoulder bursitis and impingement.
Shoulder osteoarthritis (less common) - Refers to wear and tear changes of the shoulder joint, which can be seen in association with shoulder bursitis.
Other conditions that can cause shoulder bursitis are inflammatory-type arthritis (like Rheumatoid arthritis) and infection of the bursa (septic bursitis), but these are less common.

What are the clinical features of shoulder bursitis?

The usual symptoms of shoulder bursitis are:

Shoulder pain that you can feel at the front or back of the shoulder. The pain can also go down and be felt in the upper arm.
The pain worsens when lifting your arm (like reaching for a shelf).
Reduced range of movement due to pain. Therefore, the condition sometimes is referred to as painful arc syndrome.
Weakness in the shoulder when trying to lift the arm. This could be due to the shoulder pain that limits the movement, but true weakness can indicate the presence of a rotator cuff tear.
The pain may affect your sleep and normal daily activities in severe cases.

How to diagnose shoulder bursitis?

Usually, the condition is suspected clinically, but imaging is required to confirm the diagnosis. Ultrasound is an excellent modality to assess the rotator cuff tendons for any tendinosis, tear, or subacromial bursitis changes. It can also evaluate the rotator cuff muscles for any changes in size. Most importantly, Ultrasound guidance is extremely useful when performing a steroid injection into the bursa. Plenty of evidence shows that injections done under ultrasound guidance result in better outcomes, with better pain relief and improved function. Shoulder X-Ray can also provide helpful information about the shoulder and AC joint and confirm the presence of calcification when suspected on ultrasound. MRI examination is also beneficial for the assessment of rotator cuff problems.

What is the treatment for shoulder bursitis?

Management of shoulder bursitis usually starts by targeting the underlying cause by addressing any obvious reason for irritation of the bursa. In addition, a physiotherapy exercise program is often required along with anti-inflammatory tablets, icing the area, activity modification to avoid any movements that can worsen the condition, and education about activities, posture and daily activities.

Ultrasound-guided steroid injection for shoulder bursitis

If the above-mentioned measures are not helping, especially if your pain severely affects sleep and daily activities, then a sub-acromial bursa steroid injection is usually indicated. Injecting under ultrasound guidance is very useful as it allows for live visualisation of the needle to ensure accurate placement into the bursa at the site of inflammation. Ultrasound guidance usually results in more accurate, less painful and faster procedures, with better outcomes than doing these injections without guidance.

How does steroid injection help with shoulder bursitis?

Corticosteroid (cortisone) is a potent anti-inflammatory medicine routinely used to manage inflammatory conditions (like bursitis, arthritis and tendinosis). For example, they are commonly used in managing shoulder bursitis to reduce inflammation and allow the patient to manage the condition, usually by undergoing physiotherapy and strengthening the rotator cuff muscles.

The common type of steroid injection for subacromial bursa injection is methylprednisolone (Depo-medrone). This long-acting preparation usually takes a few days to start working. Current evidence suggests that cortisone can improve pain and function for up to 3 months, but in some cases, it can last longer. The injections also contain a local anaesthetic that provides immediate pain relief lasting a few hours. Please read our article about shoulder bursitis steroid injection to find out more.

Are steroid injections for shoulder bursitis safe?

Generally, steroid injections for shoulder bursitis are very safe, with few reported side effects and complications. However, the procedure must be done under ultrasound guidance to ensure injecting the medicine accurately into the bursa. Inadvertent administration of the steroid into the adjacent rotator cuff (supraspinatus) tendon can cause tendon weakening and thus should be avoided. Initial ultrasound assessment is very important for the same reason, as it will rule out the presence of a significant rotator cuff tear, which can be a contraindication (reason not to perform) of the injection. In this case, obtaining an opinion from a specialist shoulder surgeon would be recommended. There is a minimal risk of infection, but this is very rare (1 in 10000).

Are shoulder bursitis injections painful?

Usually, the pain is minimal when the procedure is done under ultrasound guidance to ensure it is quick and accurate. The needle is very fine, and some do not feel the needle at all.

Will my shoulder hurt after bursa injection?

It is reported that some people might feel pain for a few days after the injection. This is referred to as a “steroid flare”. The pain can be more if you have undergone a barbotage procedure for calcific tendonitis. Usually, resting in the area for a couple of days and avoiding strenuous activities is sufficient. If needed, painkillers and anti-inflammatory tablets can help control pain until the steroid effect starts.

Summary

Sub-acromial shoulder bursitis is a common shoulder problem that can cause significant pain affecting shoulder movement and function. Ultrasound assessment is necessary to establish the diagnosis and rule out the presence of a rotator cuff tendon tear. It is also instrumental in guiding corticosteroid injection into the bursa if conservative management is not helping.