Frozen shoulder, known as adhesive capsulitis, presents a challenging condition characterised by pain, stiffness, and restricted mobility in the shoulder joint. While conventional treatments like physiotherapy and corticosteroid injections are commonly utilised to manage symptoms, some cases may necessitate more aggressive interventions. Hydrodistension, also called hydrodilatation, has emerged as a promising therapeutic avenue for individuals grappling with frozen shoulder.

Mechanism of Action

Frozen shoulder's underlying pathology involves inflammation and fibrosis of the joint capsule, resulting in adhesions and contractures that limit shoulder movement. Hydrodistension aims to tackle these issues by mechanically stretching the tight capsule and disrupting adhesions, thereby enhancing tissue flexibility and restoring mobility.

During the procedure, a blend of corticosteroid, a large volume of sterile saline solution, and a local anaesthetic (such as lidocaine) is injected into the joint capsule under ultrasound guidance. The pressure generated by the fluid distends or expands the capsule, stretching the surrounding tissues and breaking up adhesions. Furthermore, the local anaesthetic provides temporary pain relief, facilitating a more comfortable stretching of the shoulder joint.

The mechanical stretching induced by hydrodistension initiates a series of physiological responses within the joint tissues. Firstly, it prompts the release of cytokines and growth factors, which foster tissue remodelling and repair. Secondly, it enhances blood flow to the area, aiding in the delivery of oxygen and nutrients crucial for healing. Lastly, it disrupts the pain-spasm cycle, diminishing pain perception and enhancing muscle relaxation.

Hydrodistension Procedure Steps

• Patient Preparation: The patient is positioned comfortably on an examination table, typically in a supine position. The shoulder area is exposed and sterilised to minimise the risk of infection.

• Anaesthesia Administration: Local anaesthesia is administered to numb the skin and underlying tissues, alleviating discomfort during the procedure. This involves the use of a local anaesthetic injection.

• Ultrasound Guidance: A real-time imaging technique, ultrasound, is utilised to visualise the shoulder joint and guide the placement of the needle for precise injection. This ensures accurate delivery of the saline solution into the joint capsule.

• Injection Procedure: A needle is inserted into the shoulder joint space under ultrasound guidance. A mixture of corticosteroid, local anaesthetic and sterile saline is then injected into the joint capsule, gradually distending it and stretching the surrounding tissues.

• Post-Procedure Care: After the hydrodistension procedure, the patient may experience temporary soreness or discomfort in the shoulder area. Ice packs and over-the-counter pain relievers may be recommended to alleviate these symptoms. Patients are typically advised to avoid strenuous activities for a short period following the procedure to allow for adequate recovery.

Benefits of Hydrodistension Over Corticosteroid Injections

While corticosteroid injections are frequently used to manage pain and inflammation associated with frozen shoulder, they primarily offer symptomatic relief and do not address the underlying adhesive capsulitis. In contrast, hydrodistension presents several distinct advantages:

• Mechanical Stretching: Hydrodistension mechanically stretches the tight joint capsule and breaks up adhesions, addressing the underlying pathology of frozen shoulder and promoting long-term improvement in mobility.

• Pain Relief: In addition to stretching the capsule, hydrodistension provides immediate pain relief through the administration of a local anaesthetic, allowing for more comfortable stretching of the shoulder joint.

• Minimal Side Effects: Hydrodistension is a minimally invasive procedure with a low risk of complications.

• Potential for Long-Term Improvement: While corticosteroid injections may provide temporary relief, the benefits are often short-lived, and repeated injections may be necessary. Hydrodistension has the potential to produce more lasting improvements in shoulder function by addressing the underlying adhesive capsulitis.

In summary, hydrodistension emerges as a valuable therapeutic option for individuals battling frozen shoulder, offering mechanical stretching of the joint capsule, immediate pain relief, and the potential for long-term enhancement in mobility. By disrupting adhesions and promoting tissue flexibility, hydrodistension addresses the underlying pathology of adhesive capsulitis, presenting an effective alternative to standalone corticosteroid injections. As part of a comprehensive treatment approach, hydrodistension can aid individuals in regaining shoulder function and enhancing their quality of life.