Frozen Shoulder (Adhesive Capsulitis)

Codman introduced the term “frozen shoulder” in 1934 to describe patients who had a painful loss of shoulder motion with normal radiographic studies. In 1946, Neviaser named the condition “adhesive capsulitis” based on the radiographic appearance with arthrography, which suggested “adhesions” of the capsule of the GH joint limiting overall joint space volume. Patients with adhesive capsulitis have a painful restriction of both active and passive GH joint motion in all planes, or a global loss of GH joint motion.

This condition most commonly occurs in patients 40 to 60 years of age, with a higher incidence in females. The onset of an “idiopathic” frozen shoulder has been associated with extended immobilization, relatively mild trauma (e.g., strain or contusion), and surgical trauma, especially breast or chest wall procedures. Adhesive capsulitis is associated with medical conditions such as diabetes, hyperthyroidism, ischemic heart disease, inflammatory arthritis, and cervical spondylosis. The most significant association is with insulin-dependent diabetes. Bilateral disease occurs in approximately 10% of patients, but can be as high as 40% in patients with a history of insulin-dependent diabetes.

Adhesive capsulitis is classically characterized by three stages. The length of each stage is variable, but typically the first stage lasts for 3 to 6 months, the second stage from 3 to 18 months, and the final stage from 3 to 6 months.

The first stage is the “freezing” phase, characterized by the onset of an aching pain in the shoulder. The pain is usually more severe at night and with activities, and may be associated with a sense of discomfort that radiates down the arm. Often, a specific traumatic event is difficult for the patient to recall. As symptoms progress, there are fewer arm positions that are comfortable. Most patients will position the arm in adduction and internal rotation. This position represents the “neutral isometric position of relaxed tension for the inflamed glenohumeral capsule, biceps, and rotator cuff.” Unfortunately, many of these patients are initially treated with immobilization, which only worsens the “freezing” process.

The second stage is the progressive stiffness or “frozen” phase. Pain at rest usually diminishes during this stage, leaving the patient with a shoulder that has restricted motion in all planes. Activities of daily living become severely restricted. Patients complain about their inability to reach into the back pocket, fasten the bra, comb the hair, or wash the opposite shoulder. When performing these activities, a sharp, acute discomfort can occur as the patient reaches the restraint of the tight capsule. Pain at night is a common complaint and is not easily treated with medications or physical modalities. This stage can last from 3 to 18 months.

The final stage is the resolution or “thawing” phase. This stage is characterized by a slow recovery of motion. Aggressive treatment with physical therapy, closed manipulation, or surgical release may accelerate recovery, moving the patient from the frozen stage into the thawing phase, as long as ROM activities are practiced daily.

The diagnosis of adhesive capsulitis may be suggested by a careful history and physical examination. The history should focus on the onset and duration of symptoms, a description of any antecedent trauma, and any associated medical conditions. The findings on the physical examination vary depending on the stage at which the patient presents for treatment. In general, a global loss of active and passive motion is present; the loss of external rotation with the arm at the patient’s side is a hallmark of this condition. The loss of passive external rotation is the single most important finding on physical examination and helps to differentiate the diagnosis from a rotator cuff problem because problems of the rotator cuff generally do not result in a loss of passive external rotation. The diagnosis of a frozen shoulder is confirmed when radiographic studies are normal. Posteriorly dislocated shoulders also lack external rotation and abduction, but the axillary lateral x-ray reveals a dislocated humeral head. The differential diagnoses for shoulder stiffness are listed in Table 3–6. The physician should also be aware of possible underlying disorders that may have caused the adhesive capsulitis (e.g., a painful rotator cuff tear that caused the patient to stop using the arm).

Treatment
Even though adhesive capsulitis is believed to be a “self-limiting” process, it can be severely disabling for months to years and, as a result, requires aggressive treatment once the diagnosis is made. Initial treatment should include an aggressive physical therapy program to help regain shoulder motion. For patients in the initial painful or freezing phase, pain relief may be obtained with a course of anti-inflammatory medications, the judicious use of GH joint corticosteroid injections, or therapeutic modality treatments. Intra-articular corticosteroid injections may help to abort the abnormal inflammatory process often associated with this condition. The rehabilitation program for adhesive capsulitis is outlined on page 229. An algorithm for the treatment of shoulder stiffness is shown in Figure 3–71.

Operative intervention is indicated in patients who show no improvement after a 3-month course of aggressive management that includes medications, corticosteroid injection, and physical therapy. In patients who do not have a history of diabetes, our initial intervention is a manipulation under anesthesia followed by outpatient physical therapy as outlined on page 229. Patients with a history of diabetes in whom conservative management fails and patients who fail to regain shoulder motion after manipulation are treated with an arthroscopic surgical release followed by physical therapy.