What is the hallmark sign of rotator cuff tendinopathy on inspection?

• A. Weakness with abduction and external rotation, often with night pain
• B. Joint deformity
• C. Swelling
• D. Heat and redness

Answer: (A)

Weakness with resisted abduction and external rotation is the telltale sign because the rotator cuff muscles are responsible for lifting the arm (primarily the supraspinatus) and for externally rotating the shoulder (infraspinatus and teres minor). Tendinopathy compromises these tendons, so normal-looking shoulders may still show reduced strength during these movements, even if there isn’t visible deformity. Night pain is common with rotator cuff disease, but the core observable feature during examination is the weakness in these specific motions.

Joint deformity, swelling, and heat are not typical hallmarks of rotator cuff tendinopathy; those findings point more toward inflammatory, infectious, or structural issues elsewhere in the shoulder joint.