This may occur with activity, particularly shoulder activity above the horizontal position, but may also be present at rest in bed. Pain-restricted movement above the horizontal position may be present, as well as weakness with shoulder flexion and abduction.Abnormal mobility or function of the scapula (scapular dyskinesia) may be present and is related to lower functional scores; it unclear whether scapular dyskinesia is a cause, effect or compensation for rotator cuff pathology. Risk factors
Epidemiological studies strongly support a relationship between age and cuff tear prevalence, with the most common cause being age-related degeneration and, less frequently, sports injuries or trauma.Those most prone to failed rotator cuff syndrome are people 65 years of age or older; and those with large, sustained tears. Smokers, people with diabetes, individuals with muscle atrophy or fatty infiltration, and those who do not follow postoperative-care recommendations also are at greater risk. In a 2008 study the frequency of such tears increased from 13% in the youngest group (aged 50–59 y) to 20% (aged 60–69 y), 31% (aged 70–79 y), and 51% in the oldest group (aged 80–89 y).Some risk factors such as increased age and height cannot be changed. Increased body mass index is also associated with tearing. Recurrent lifting and overhead motions are at risk for rotator cuff injury as well. This includes jobs that involve repetitive overhead work, such as carpenters, painters, custodians, and servers.
The technique is not considered appropriate for older people, or those with pre-operative stiffness or nerve injuries. People diagnosed with glenohumeral arthritis and rotator cuff anthropathy have the alternative of total shoulder arthroplasty, if the cuff is largely intact or repairable. If the cuff is incompetent then a reverse shoulder arthroplasty is available and, although not as robust a prosthesis, does not require an intact cuff to maintain a stable joint. Diagnosis
Diagnosis is based upon physical assessment and history, including description of previous activities and acute or chronic symptoms. A systematic, physical examination of the shoulder comprises inspection, palpation, range of motion,  provocative tests to reproduce the symptoms, neurological examination, and strength testing. The shoulder should also be examined for tenderness and deformity. Since pain arising from the neck is frequently referred to the shoulder, the examination should include an assessment of the cervical spine looking for evidence suggestive of a pinched nerve, osteoarthritis, or rheumatoid arthritis. Neer promoted the concept of three stages of rotator cuff disease. Stage I, according to Neer, occurred in those younger than 25 years and involved edema and hemorrhage of the tendon and bursa. Stage II involved tendinitis and fibrosis of the rotator cuff in 25- to 40-year-olds. Stage III involved tearing of the rotator cuff (partial or full thickness) and occurred in those older than 40 years. For surgical purposes, tears are also described by location, size or area, and depth.