What Causes Shoulder Periarthritis?

Chronic overuse injury is the most common cause of adhesive capsulitis (frozen shoulder). Prolonged physical labor inevitably involves frequent use of the shoulders. In particular, the soft tissues surrounding the glenohumeral joint are relatively weak and thus prone to overuse injury. When such injury occurs, the surrounding muscles, tendons, ligaments, and fascia may become congested and exudative, leading to aseptic inflammation of the periaricular tissues and consequent restriction of shoulder joint mobility. Occasionally, even minor strains that are not promptly or effectively treated can accumulate over time and eventually result in adhesive capsulitis.

As we age, various bodily functions gradually decline; combined with prolonged physical inactivity, this significantly increases the risk of developing adhesive capsulitis in later life. Moreover, adhesive capsulitis occurs more frequently during winter and spring, suggesting a close association between fluctuations in ambient temperature and disease onset. Cold exposure to the shoulder joint may slow local blood flow and induce muscle spasm, resulting in shoulder pain and restricted movement. Additionally, certain systemic diseases are linked to the development of adhesive capsulitis. For example, disorders affecting the heart, lungs, or biliary tract may cause referred shoulder pain; if these underlying conditions remain untreated for extended periods, the shoulder muscles may remain chronically spastic and ischemic—ultimately progressing to adhesive capsulitis.