Surgical Management of Frozen Shoulder

Introduction:

Frozen shoulder or adhesive capsulitis is a painful condition that causes a restricted range of motion (ROM) due to inflammation of the glenohumeral joint's synovial fluid, causing the capsule's fibrosis, in turn, results in sudden onset and gradual increase of pain. Still, it is a self-limiting disorder with complete recovery of pain and range of motion. It occurs most commonly in women, and about 50 percent of patients experience pain and stiffness of the shoulder at a mean of seven years from the onset of the disease.

What Are the Symptoms of Frozen Shoulders?

The symptoms of a frozen shoulder include:

• Sudden onset of pain on one side of the shoulder.

• Pain and stiffness in the deltoid muscle region (the muscle that connects the joint of the shoulder to the trunk), which causes difficulty in elevation, and external rotation of the arm.

• Cannot rest the body on the affected region.

What Are the Causes of Frozen Shoulders?

The causes are classified into primary and secondary. The cause for the primary frozen shoulder is idiopathic (the cause is unknown and cannot be identified). The causes of secondary frozen shoulder include:

• Systemic conditions such as thyroid disorders, hypoadrenalism, diabetes mellitus, cardiopulmonary stroke, and hyperlipidemia (increased fat like cholesterol and triglycerides in the blood).

• Surgery or radiation therapy for breast cancer.

• Proximal humeral fracture (fracture of the upper part of the arm) or clavicle fracture (fracture of the collar bone).

• Dislocation of the joint.

• Soft tissue injury of the shoulder.

• Post-operative immobilization of the upper limb.

• Osteoarthritis (degenerative joint disease).

• Rotator cuff tendinopathy (inflammation of the tendons of the shoulder).

• Calcific tendinitis (inflammation of tendons along with calcium deposits).

• Parkinson's disease (degenerative nerve disorder).

• Complex regional pain syndrome (chronic pain that affects arms or legs).

• Cancer.

What Are the Stages of Frozen Shoulders?

There are three stages of a frozen shoulder which include:

• Freezing/Early Stage (Two to Nine Months): There is sudden, severe onset of pain, stiffness, and progressive loss of motion. In this stage, therapeutic ultrasound, cryotherapy (cold therapy which reduces pain and inflammation), or transcutaneous electrical nerve stimulation (TENS) unit (a device that reduces pain by using electrical impulses)can be given. Following a doctor's recommendation, individuals are able to purchase the TENS.

• Frozen Stage (Four to 12 Months):There is evident stiffness, but pain levels are reduced.

• Thawing/Developed Stage (12 to 42 Months): Gradual shoulder joint recovery with reduced or no pain.

What Is the Pathophysiology of Frozen Shoulders?

The fibroblasts and myofibroblasts cells of the capsule produce densely packed collagen type III in the extracellular matrix of the articular capsule, which leads to reduced intra-articular volume (around 5 milliliters instead of around 20 milliliters) and capsular compliance, which affects the superior and inferior glenohumeral ligaments, capsule, rotary interval (triangular space in the upper part of the shoulder), and coracohumeral ligament (the fibrous structure that stabilizes the joint) and all these leads to fibrotic and inflammatory tightening of the joint capsule. This synovitis (inflamed synovial fluid in the joint) is associated with increased fibrotic growth factors, inflammatory cytokines, and interleukins. However, reversing these pathological changes is possible because many patients have recovered within one to three years.

What Is the Diagnosis of Frozen Shoulder?

The diagnosis of a frozen shoulder includes:

• Ultrasound scanning shows the presence of an accumulation of fluid around the long head of the biceps tendon and the thickening of the coracohumeral ligament (characteristic feature).

• Magnetic resonance imaging (MRI) may show thickening of the coracohumeral ligament and glenohumeral joint capsule.

• Magnetic resonance imaging arthrography may show reduced joint space.

What Is the Differential Diagnosis of Frozen Shoulder?

The differential diagnosis of the frozen shoulder includes:

• Subacromial impingement syndrome (inflammation of the shoulder tendons, which results in shoulder pain).

• Rotator cuff tendinopathy.

• Post-stroke shoulder subluxation.

• Dupuytren disease (a condition where the tissue beneath the skin of the hand is fibrous and thickened).

• Referred pain from the cervical spine.

• Malignancy like Pancoast tumors (tumors that form in the upper part of the lungs).

What Is the Non-surgical Management of Frozen Shoulder?

The non-surgical management of a frozen shoulder includes:

• Use of painkillers, if the pain is in the initial stage, analgesics like Acetaminophen, non-steroidal anti-inflammatory drugs (NSAID) like Ibuprofen and Naproxen, and corticosteroids are used in the treatment of frozen shoulder.

• Physiotherapy is based on stretching the muscles and mobilizing soft tissues. There are stretching (pendulum exercises, pulley exercises, towel stretch, finger walk, cross-body reach, armpit stretch, outward and inward rotation) and strengthening exercises (posterior capsule stretch, isometric shoulder external rotation, and scapular retraction).

• Injection of glenohumeral corticosteroids in the subacromial space of the shoulder using ultrasonographic or fluoroscopic guidance for needle placement.

• Capsular hydro dilatation in which saline is injected into the joint capsule.

What Is the Surgical Management of Frozen Shoulder?

Surgical treatment should be done when there is a failure in conservative treatment (medication, local injections, or physiotherapy) and no improvement in the functional disability after three to six months. Surgical treatment includes:

• Manipulation Under Anesthesia (MUA): Involves tearing the thickened inflamed capsule and tightened ligaments. It is done under general anesthesia in the supine position and around six to nine months from the onset of infection. First, the shoulder joint capsule is stretched and torn with manipulation. The manipulation sequence is repeated until a maximum range of movements is obtained. When there is tissue breakdown, a snap or cracking sound is heard. After MUA, the patient should continue physiotherapy for one week. It is a time-efficient procedure, easy to perform, and results in rapid restoration of the movements. Still, it can cause shoulder dislocation, humeral shaft or glenoid rim fracture, and injury to the brachial plexus, cartilage, or rotator cuff.

• The Capsular Release (Open or Arthroscopic): Arthroscopic capsular release has improved visualization of the inferior capsule and less postoperative bleeding and pain due to controlled release without manipulation. It is done under conscious sedation, and an interscalene block is given. Anterior and posterior portals are established, and an arthroscope is introduced through the posterior portal, reaches the glenohumeral joint, and in the anterior portal reaches the rotator interval, which shows fibrosis and capsular thickening the tissue around the capsular joint is cut using radiofrequency waves, or by cauterization and any bleeding is controlled by electrocautery. Recovery is achieved within six weeks to three months and should be followed by physiotherapy.

Conclusion:

The sudden onset and severity of pain can deprive patients of their routine life and occupational activities. Therefore, the appropriate treatment depends on the pain stage. Still, definitive treatment plans have yet to be established, and many different management plans are used depending on the patient's response to the treatment.