Signs, symptoms, and assessment (diagnosis) of frozen shoulder

Signs and Symptoms of frozen shoulder:

Scapular elevation as a compensation for frozen shoulder decreased glenohumeral joint abduction. Permission: Joseph E. Muscolino.

The most common sign of frozen shoulder is decreased range of motion (ROM). Of the six cardinal ranges of glenohumeral (GH) motion, the most commonly affected motions are abduction, flexion, and lateral rotation. It is common for the client to compensate for a decreased range of GH motion by increasing shoulder girdle or trunk motion. For example, if arm abduction is decreased, the client might increase scapular elevation or even laterally flex the trunk to the opposite side in an attempt to raise the hand higher.

Regarding symptoms, the loss of motion of frozen shoulder often has no accompanying pain. The client simply cannot move their arm fully in one or more ranges of motion. Or, if pain is present, it only occurs if the client tries to move the arm beyond the point of limitation (tissue tension mechanical barrier). In fact, the lack of pain is often a predisposing factor in the progression of frozen shoulder. Because their shoulder does not hurt, the client often does not feel the need to address the condition until it has progressed to the point that it functionally limits their ability to perform necessary activities of daily life. By this point it time, the condition has often existed for many months and the neural pattern of muscle hypertonicity is more patterned and the degree of fibrous fascial adhesions is great. And if pain with attempted movement is present, it further discourages the client from attempting to remedy the condition.

Assessment/ Diagnosis of frozen shoulder:

Assessing/diagnosing frozen shoulder is straightforward. Simply evaluate the client’s GH motion in all six cardinal ranges of motion (flexion, extension, abduction, adduction, lateral rotation, and medial rotation). If a ROM is decreased and there is no evidence of another pathologic condition that is causing or contributing to the hypomobility, the assessment of frozen shoulder can be made. Standard ideal ranges of motion for the arm are shown in Table 1. Keep in mind that these are average ideal ranges of motion for a healthy young adult. As a person ages, it is expected that there will be a decrease in these ranges. Table 2 shows the average ranges of motion for the entire shoulder joint complex. These motions include the coupling of motions of the arm at the GH joint with the shoulder girdle at the scapulocostal (ScC; also know as scapulothoracic), sternoclavicular (SC), and acromioclavicular (AC) joints; this coupling is referred to as scapulohumeral rhythm. Therefore, when you are evaluating the range of motion of the patient’s/client’s arm, you are assessing the complex of GH and shoulder girdle motions. When performing these ranges of motion, it is best to assess passive motion, not active, because active motion could be decreased because of muscle weakness. This would most likely occur in an elderly client/patient.

Table 1 Average Ranges of Motion in degrees of the Glenohumeral Joint

Table 1 Average Ranges of Motion in degrees of the entire Shoulder Joint Complex

Although frozen shoulder is easily assessed with physical examination, medically, it is common for a physician to order some type of radiographic examination such as X-ray or MRI. This is often done primarily to rule out other conditions. The functional aspect of frozen shoulder is difficult to diagnose on MRI, but can be inferred from the thickening of the capsule and capsular ligaments.

Differential diagnosis/assessment of frozen shoulder:

As stated above, frozen shoulder often follows or accompanies the presence of another condition. If another condition was present and has not resolved, this must be considered when determining treatment. Therefore a thorough diagnosis/assessment that assesses for frozen shoulder as well as the presence of other possible conditions is extremely important. Further, because frozen shoulder is somewhat an diagnosis/assessment of exclusion, meaning that if no other condition is found, it can be more confidently asserted that the patient’s/client’s decreased motion must be due to frozen shoulder, then differentially diagnosing/assessing to rule out other conditions assists in the assessment to rule in frozen shoulder.

Other conditions that cause decreased shoulder range of motion and therefore might lead the therapist to incorrectly assess the client/patient with frozen shoulder are degenerative joint disease (DJD, also known as osteoarthritis or OA) of the GH joint, GH hypomobility joint dysfunction (subluxation/misalignment) due to decreased nonaxial joint play, and dysfunction/hypomobility of the joints of the shoulder girdle (scapulocostal, sternoclavicular, and acromioclavicular joints).