Pathogenesis (development of disease)
Adhesive inflammation of the shoulder joint capsule results from degenerative changes with calcification, swelling, etc. of the shoulder.
Lesions of the rotator cuff (group of four muscles and their tendons that form the roof of the shoulder joint and extend from the scapula to the greater or lesser tuberosity of the humerus) occur as a result of indirect, and less commonly direct, force against a decreased mechanical load-bearing capacity of the rotator cuff. This decreased load-bearing capacity is due to a variety of internal and external factors such as recurrent microtrauma (minute injuries), genetics, or drug toxicity.
Impingement syndrome of the shoulder describes pain symptoms resulting from narrowing of the space between the supraspinatus muscle and the acromion (tightness syndrome). A deficient rotator cuff is thought to be responsible for its development.
Etiology (causes)
Biographic causes
- Anatomic variants – variations in the shape of the bones and soft tissues involved that drive degenerative processes.
Behavioral causes
- High-risk sports such as throwing sports
Disease-related causes
Injuries, poisonings and other consequences of external causes (S00-T98).
- Trauma (injury) of the shoulder, unspecified.
Medication
- Steroids are suspected (studies show low evidence for this).