What is a Frozen shoulder?
Frozen shoulder (or adhesive capsulitis) is a condition characterised by generalised inflammation of the shoulder joint capsule (the soft tissues and ligaments surrounding the shoulder). It can happen following trauma or surgery and is more common in diabetic patients. To find out more, please read our article about Frozen shoulder. It typically results in shoulder pain, stiffness and reduced range of movement.
What is shoulder hydrodistension?
Hydrodistension is a special procedure used to treat frozen shoulder/adhesive capsulitis. It is usually considered if the symptoms of a frozen shoulder are severe (for example, severe pain interfering with patients' sleep and severe restriction of shoulder movement). It is also considered if conservative treatments (like physiotherapy and anti-inflammatory tablets) are ineffective.
What does shoulder hydrodilatation/hydrodistension involve?
The procedure involves injecting a high volume of sterile (clean) water (approx. 20-30 mls) with steroids and numbing medications inside the shoulder joint. The aim is to stretch the inflamed and tight joint capsule and reduce the inflammation within the joint via the strong anti-inflammatory effect of the steroids. The type of steroid used is a long-acting preparation called Kenalog (triamcinolone acetonide). Please read our article about steroid injection for shoulder joint to learn more. A numbing medicine is usually used to ensure the procedure is well-tolerated with minimal discomfort. Evidence shows that hydrodilatation provides short-term pain relief and improvement in the range of movement that continue into the medium and long term (ladermann et al 2021). Hydrodistension needs to be done under imaging guidance (either ultrasound or x-ray). It is important to follow shoulder hydrodistension by a specialist physiotherapy program to enhance the procedure results.
How is shoulder hydrodistension done?
First, the doctor will explain the procedure to you on the day, answer your questions and complete a consent form. Then a shoulder ultrasound examination is usually performed to assess the rotator cuff tendons and rule out other causes of shoulder pain like subacromial bursitis. You will be positioned appropriately for the procedure. The injection is usually done from the back of the shoulder. You will be either sitting on the couch with your back towards the doctor or lying on your side (lying on the other shoulder). In both cases, your doctor will usually ask you to put your hand across your chest to increase the space at the back of the shoulder.
We always recommend performing shoulder injections under ultrasound guidance for more accurate results and less painful and faster procedures. The doctor will clean the skin using an antiseptic solution and prepare and drape the area using an aseptic technique. This means using an extremely clean non-touch technique, sterile gloves and equipment to minimise the risk of infection.
Then, a small needle will be used to administer numbing medication (called lidocaine) to the skin and the deeper tissues. The needle will be advanced carefully while injecting more numbing medicines and under continuous ultrasound guidance until the needle tip is accurately placed inside the shoulder joint. Then, more numbing medicine will be injected inside the shoulder joint to numb the capsule and ensure correct intra-articular placement. After that, the steroid and the normal saline will be slowly injected into the joint, and the needle will be removed. A small plaster will be put on the area. The length of the procedure depends on the difficulty of the case and the doctor's experience. Usually, 30 minutes is a reasonable time for the whole procedure.
What to expect during/after shoulder hydrodistension?
You may feel a gradual build-up of pressure inside the shoulder. This is expected as shoulder hydrodistension involves injecting a good volume of sterile normal saline into the joint. The doctor will keep checking on you during the procedure. Some patients may feel gentle pressure going down the arm. When the procedure is done, your shoulder might feel heavy and tight for a few days, although some patients report immediate improvement in their symptoms.
The fluid can be seen accurately distending the joint in the video.
Can a shoulder hydrodistension procedure be repeated?
The answer is yes. We can consider repeating the procedure after a few months in cases of a severe frozen shoulder when the response from one procedure is inadequate. To learn more about other treatment options for a frozen shoulder, please see our article regarding the treatment of a frozen shoulder.
What are the possible complications of shoulder hydrodistension?
The complications are very rare in general. There is a very small risk of infection (less than 1 in 10.000), similar to any other steroid injection.
Please read our article about shoulder hydrodilatation/hydrodistension to find out more.
Shoulder conditions and treatments
