Continuing Education Activity

Adhesive capsulitis, also known as frozen shoulder, is an inflammatory condition characterized by shoulder stiffness, pain, and significant loss of passive range of motion. Long-term disability has been reported at ten to twenty percent in patients, and the persistence of symptoms at thirty to sixty percent. Adhesive capsulitis has a prevalence of approximately 2% to 5% in the general population. The mean age of onset is typically 55. There is a slightly greater predominance in females (1.4:1). The exact pathophysiology of adhesive capsulitis is unknown. This activity reviews the evaluation and management of adhesive capsulitis and highlights the role of the interprofessional team in caring for patients with this condition.

Objectives:

• Identify the characteristic features and risk factors associated with adhesive capsulitis to facilitate early diagnosis.
• To optimize patient outcomes, implement evidence-based treatment strategies, including physical therapy and pain management techniques.
• Communicate effectively with patients, clearly explaining the condition, treatment options, and expected outcomes.
• Collaborate with other healthcare professionals, such as orthopedic surgeons and physical therapists, to develop comprehensive care plans for patients with adhesive capsulitis.

Introduction

Adhesive capsulitis, commonly known as frozen shoulder, is an inflammatory condition causing shoulder stiffness and pain. Diagnosis is based on the American Academy of Orthopedic Surgeons' definition, which emphasizes the gradual development of global limitation of shoulder motion without significant radiographic findings.[1][2] Assessing significant loss of passive range of motion is vital for accurate diagnosis.[3]

Etiology

Adhesive capsulitis can be classified into primary and secondary forms. Primary adhesive capsulitis is typically idiopathic and has a gradual onset. It is often associated with underlying conditions such as diabetes mellitus, thyroid disease, drugs, hypertriglyceridemia, or cervical spondylosis.[4][5]

Secondary adhesive capsulitis is typically the result of shoulder trauma, injuries such as rotator cuff tears, fractures, surgery, or prolonged immobilization.[6]

Epidemiology

Adhesive capsulitis has a prevalence of approximately 2% to 5% in the general population, with a mean onset of age of 55. There is a slightly more significant predominance in females (1.4:1), and the non-dominant hand is often affected. Patients with autoimmune comorbidities, such as thyroid disorders and diabetes mellitus, are more prone to developing adhesive capsulitis.[7] Additionally, individuals with diabetes may experience poorer treatment outcomes, which the duration of their diabetes can influence.[8]

Pathophysiology

The precise pathophysiology of adhesive capsulitis remains uncertain. The prevailing hypothesis suggests inflammation initiates within the joint capsule and synovial fluid, followed by reactive fibrosis and adhesions in the synovial lining. The initial inflammation of the capsule causes pain, while the capsular fibrosis and adhesions reduce the range of motion.[9]

Histopathology

The exact histopathological features of adhesive capsulitis can vary between individuals and stages of the condition. It is widely understood that adhesive capsulitis is a condition that involves both inflammation and fibrosis, and the condition passes through several stages, which include an initial inflammatory phase, a fibrotic phase characterized by increasing stiffness and limited range of motion (ROM), and a thawing or regression phase, where gradual improvement in shoulder mobility occurs. The duration of each stage can vary among individuals.[6]

Arthroscopic studies of the affected shoulder show:[10][11]

• Subacromial fibrosis: The presence of fibrous tissue and adhesions in the subacromial space, leading to restricted movement and impingement of the shoulder structures.
• Proliferative synovitis: The synovium lining the joint capsule may show signs of excessive proliferation and inflammation, contributing to the thickening of the synovial tissue.
• Capsular thickening: The joint capsule itself may exhibit thickening and fibrosis, leading to a loss of ROM and shoulder joint stiffness.

These arthroscopic findings support the diagnosis of adhesive capsulitis and provide visual evidence of the pathological changes occurring within the joint.[12]

History and Physical

Patients with adhesive capsulitis usually present with a gradual onset of shoulder pain that worsens over weeks to months. This is followed by significant limitations in shoulder motion. The key clinical sign of adhesive capsulitis is a reduction in active and passive ROM, specifically in forward flexion, abduction, and external and internal rotation. In addition, severe cases may exhibit loss of the natural arm swing during walking and muscular dystrophy.[13][14]

Palpation of the affected shoulder reveals diffuse tenderness around the shoulder joint. The distal neurology must remain intact. Resisted shoulder movement elicits pain and marked limitation, resembling a rotator cuff tear. Internal rotation may be measured using the Apley scratch test.[13][15]

Evaluation

During a physical exam, patients with adhesive capsulitis may exhibit a decreased glenohumeral ROM and experience pain during testing. Pain will often limit a complete and thorough physical exam. Typically, there is a significant reduction in the active and passive ROM in 2 or more planes of motion compared to the unaffected side. The loss of ROM usually follows a specific pattern starting with external rotation, followed by abduction, internal rotation, and forward flexion.[14][16]

Special tests, such as the Neer and Hawkins tests for impingement and Speed's test for biceps tendinopathy, are often positive. The diagnosis is primarily clinical, based on the history and physical exam findings described above.[17]

There is no specific laboratory testing indicated for the diagnosis of adhesive capsulitis. However, further laboratory testing may be performed if concern for an underlying systemic disease contributes to the condition.

In most cases, the diagnosis of adhesive capsulitis is primarily clinical, and imaging is not routinely indicated. However, imaging studies such as a shoulder X-ray may be considered if there is a concern about an alternative diagnosis or the need to evaluate for conditions such as fractures or other underlying pathology.

The injection test can be used as a diagnostic tool if there is uncertainty about the underlying cause of shoulder pain. During the test, the subacromial space is injected with a local anesthetic, usually 5 ml of 1% lidocaine. The ROM limitations and discomfort persist even after the injection in patients with adhesive capsulitis. However, in patients with subacromial pathology, such as rotator cuff tendinopathy or subacromial bursitis, pain may improve and increase in ROM following the injection.[18]

Magnetic resonance imaging may show rotator interval synovitis, hypertrophy of the coracohumeral ligament, loss of the subcoracoid fat triangle, and thickness of the glenohumeral joint capsule throughout the axillary pouch. Although these are characteristic findings of adhesive capsulitis but none of them are pathognomic. [19] The disappearance of the typical axillary recess on arthrography may suggest joint capsule contracture. [20]

Treatment / Management

In most cases, adhesive capsulitis is a self-limited disease with high spontaneous recovery rates within 18 to 30 months. Treatment is focused on symptomatic relief and improving ROM.[21][22] There are limited studies that guide treatment management. The following are some viable treatment options:

• NSAIDs: During the initial phase, NSAIDs can aid with pain control.[23][24]

• Physical therapy: Therapy has limited evidence supporting its benefit, but patients in recovery may benefit from specific interventions. In some cases, gentle ROM exercises, stretching, and graded resistance training have been shown to reduce pain and increase function. However, it is essential to avoid vigorous rehab, as it can worsen symptoms.[25] Patients and providers should approach therapy cautiously and closely monitor the response to ensure it is well-tolerated and does not exacerbate the condition.[26]

• Oral corticosteroids: This treatment option can provide short-term pain relief for improved ROM and function. The benefits often do not last longer than a few weeks, and clinicians should be aware of the potential side effects of oral steroid use and carefully weigh the risks and benefits when considering this treatment option.[27]

• Intra-articular steroid injection: Steroid injections have demonstrated benefits in improving function, reducing pain, and increasing ROM.[28] However, it is important to note that the duration of the effects of steroid injections is limited. Therefore, practitioners must be mindful of potential side effects associated with steroid injections. Early administration of injections in the disease course may enhance the likelihood of achieving positive outcomes. Multiple injections can be considered to provide symptomatic relief as needed.[29][30]

• Hydrodilatation: With this treatment modality, the glenohumeral capsule is injected with a combination of saline and steroid to promote capsule dilation. This treatment approach has demonstrated short-term benefits in reducing pain and improving ROM and function.[31] Current evidence suggests no significant outcome difference when comparing hydrodilatation to intra-articular steroid injection.[32]

• Manipulation under anesthesia: This is reserved for refractory cases of adhesive capsulitis that do not respond to conservative treatments. It carries a risk of humerus fractures. The procedure involves gentle manipulation of the shoulder joint in various directions. The patient's arm is supported by a small lever arm (close to the shoulder), and the shoulder is gently manipulated in flexion, abduction, external rotation, and 90° abduction.[33] No force should be applied if extra resistance is encountered. Additionally, an injection of triamcinolone mixed with bupivacaine may be administered during the procedure to prevent inflammation.[34][35]

• Arthroscopic capsular release: This is reserved for refractory cases. If symptoms do not improve with conservative measures within 10 to 12 months, referral to an orthopedic surgeon is recommended. The procedure involves releasing various joint capsule structures to improve the range of motion. The thick and contracted joint capsule may be challenging to enter; however, after making the standard posterior or lateral portal entry, rotator cuff interval, coracohumeral ligament, middle glenohumeral ligament, anterior capsule, and posterior capsule are released. The inferior capsule adhesiolysis is done by simple manipulation because of its proximity to the axillary nerve.[36] Care is taken during the procedure to avoid damage to surrounding structures. After the release, the subacromial space is inspected, and inflamed tissue and bursa may be debrided. Triamcinolone mixed with bupivacaine is injected into the shoulder joint to prevent inflammation. Following the procedure, early passive and active ROM exercises are initiated.[37][38]

  The clinical efficacy of arthroscopic capsular release compared to manipulation under anesthesia has not been conclusively established in the literature.[39][40]

• Open capsular release: Patients with strokes or head injuries and those with posttraumatic or postsurgical adhesive capsulitis with significant adhesions and contractures limiting arthroscopic surgery may be candidates for open release. Open release involves a larger incision to access and release the thickened and contracted joint capsule directly. The open procedure has higher morbidity as compared to arthroscopic capsular release.[41]

Indications for Surgery[42]

• The patient fails a trial of prednisone or NSAIDs.
• No response to glenohumeral or subacromial injections.
• No response respond to physical therapy.

Contraindications for Surgery

• The patient has had an inadequate course of steroids or NSAIDs.
• The patient has not had any attempt at conservative therapy.
• There is an acute infection.
• The patient has a concomitant malignancy in the shoulder.
• The patient has a neurological deficit or nerve complaint originating from the cervical spine.

Differential Diagnosis

The differential diagnosis for adhesive capsulitis (frozen shoulder) includes the following:[15]

• Cervical radiculopathy
• Acromioclavicular joint arthrosis
• Bicep tendinopathy
• Glenohumeral arthritis
• Fracture
• Calcifying tendinitis/synovitis
• Malignancy
• Rotator cuff impingement
• Polymyalgia rheumatica
• Shoulder impingement syndrome[43]

Staging

Disease progression is described in three clinical phases.[44] These are:

• Phase 1: The painful phase is characterized by diffuse and disabling shoulder pain, initially worse at night, along with increasing stiffness. It can last from 2 to 9 months.
• Phase 2: The frozen or adhesive phase involves a progressive limitation in ROM in all shoulder planes. The intensity of pain gradually diminishes during this phase. It typically lasts from 4 to 12 months.
• Phase 3: The thawing or regression phase is marked by a gradual return of the range of motion. The recovery of ROM may take 12 to 24 months for complete restoration.

Complications

• Residual shoulder pain and/or stiffness
• Humeral fracture[45]
• Rupture of the biceps and subscapularis tendons
• Labral tears
• Glenohumeral joint dislocation
• Rotator cuff tear[46]

Postoperative and Rehabilitation Care

The patient should enroll in a formal exercise program as part of the treatment for adhesive capsulitis.

Rehabilitation 

Rehabilitation for adhesive capsulitis aims to manage pain, maintain or improve range of motion (ROM), and facilitate a return to activity. The specific therapy approach depends on the patient's stage of the condition, age, activity level, and comorbidities. Proprioceptive neuromuscular facilitation (PNF) exercises have effectively promoted ROM and decreased pain.[47][48][49] 

Other pain reduction techniques like ultrasound and electrical stimulation are commonly used but lack consistent data to support their use. Manual therapy techniques also require further research to establish standardized consistency, dosage, and duration protocols.[50] Close collaboration between therapists and physicians is essential, as orthopedic physicians may have their rehabilitation protocols for therapists to follow.[51][52]

Consultations

Several healthcare professionals may be involved in the management and treatment process when dealing with a frozen shoulder or adhesive capsulitis. The patient's primary care physician should be the first point of contact for evaluation and initial management of the frozen shoulder. Physical therapists play a crucial role in the management of frozen shoulder. Physical therapy can help reduce pain, restore mobility, and optimize functional abilities.

In cases where a frozen shoulder significantly affects daily activities and functional abilities, an occupational therapist may be involved. They can provide strategies and assistive devices to adapt and improve the performance of everyday tasks.

An orthopedic specialist, pain management specialist, or rheumatologist can provide other possible consultations. These specialists can be consulted if the patient has severe pain or non-alleviating symptoms.

Deterrence and Patient Education

Patient education for adhesive capsulitis or frozen shoulder is an important component of its management. Some key points to include in patient education are as follows:

1. Explanation of the condition: Provide a clear and concise description of adhesive capsulitis or frozen shoulder, emphasizing that it is a self-limiting condition characterized by stiffness and pain in the shoulder joint.
2. Natural course and timeline: Frozen shoulder typically progresses through 3 phases: the painful phase, the frozen or adhesive phase, and the regression phase. The condition may take several months to years to resolve completely.
3. Range of motion exercises: Regular and gentle exercises can help improve shoulder mobility and prevent further stiffness. Working with physical therapy may improve the range of motion.
4. Patience and time frame: Set realistic expectations and assure the patient that the recovery process for a frozen shoulder takes time.
5. When to seek medical help: Severe or worsening symptoms, new-onset weakness, or numbness in the arm may warrant medical attention.

Pearls and Other Issues

• Adhesive capsulitis, also known as frozen shoulder, is an inflammatory condition characterized by shoulder stiffness and pain.
• A significant loss of passive range of motion is crucial for diagnosing a frozen shoulder in most patients.
• The exact pathophysiology is unknown. However, the most commonly accepted hypothesis states that inflammation initially occurs within the joint capsule and synovial fluid.
• Laboratory testing is not indicated for the diagnosis of adhesive capsulitis. However, if there is a suspicion of an underlying systemic disease or condition contributing to the symptoms, targeted laboratory tests may be necessary to investigate and rule out other potential causes.
• Diagnostic imaging studies are not indicated for the diagnosis of adhesive capsulitis. The diagnosis is based on clinical evaluation and patient history. However, if there is a concern regarding an alternative diagnosis, such as a fracture or other structural abnormality, imaging studies, such as a shoulder X-ray, may be helpful.
• Frozen shoulder is a self-limiting condition with a favorable outcome, especially when diagnosed early. However, to achieve satisfactory results and optimize recovery, physical therapy may play a role in the management of a frozen shoulder.

Enhancing Healthcare Team Outcomes

Patients with a frozen shoulder may present to their primary caregiver, such as a medical doctor, doctor of osteopathy, nurse practitioner, or physician assistant. If necessary, a referral to an orthopedic specialist may be appropriate. In addition, specialty care nurses play a role in evaluating patients and providing education.

It is important to recognize that a frozen shoulder is a self-limiting condition with a favorable outcome if diagnosed early. Physical therapy may be a part of treatment to achieve satisfactory results. Effective communication and accurate record-keeping among caregivers are essential, with timely referrals for additional interventions as needed. Collaborative teamwork among healthcare professionals has been shown to improve outcomes. [Level 5]

Long-term disability is reported in 10% to 20% of patients, and persistent symptoms may be experienced by 30% to 60% of patients, even after conservative management.