A "strain" can be defined as a tear of a ligament supporting a joint of the skeleton

A. Edema: Peripheral edema, especially in the lower extremities, is a hallmark sign of right-sided heart failure. It occurs due to increased venous pressure and fluid accumulation in dependent tissues. This is a classic manifestation of systemic congestion.

B. Cool legs: Cool extremities are more characteristic of left-sided heart failure or poor arterial perfusion rather than right-sided failure. Right-sided failure primarily causes systemic venous congestion rather than reduced arterial blood flow to the limbs.

C. Dyspnea: While dyspnea is more commonly associated with left-sided heart failure due to pulmonary congestion, it can also occur in right-sided failure, especially if there is concurrent left-sided dysfunction or pulmonary hypertension.

D. Nausea: Nausea can occur in right-sided heart failure due to hepatic congestion and impaired gastrointestinal perfusion. This reflects the systemic effects of venous blood backup rather than primary pulmonary involvement.

E. Anorexia: Anorexia may result from hepatic congestion and gut edema in right-sided heart failure. Venous congestion affects gastrointestinal function, leading to reduced appetite and early satiety.

A. Synovial membrane: Rheumatoid arthritis is an autoimmune disorder characterized by chronic inflammation of the synovial membrane. The inflamed synovium thickens and forms pannus, which can invade cartilage and bone. This process leads to joint pain, swelling, and progressive deformity.

B. Articular cartilage: Articular cartilage damage occurs later in the disease as a consequence of ongoing synovial inflammation. It is not the primary site of inflammation at the onset of rheumatoid arthritis. Cartilage destruction results from enzymes released by the inflamed synovium.

C. Subchondral bone: Subchondral bone erosion develops as rheumatoid arthritis progresses and pannus extends deeper into the joint. This involvement reflects advanced disease rather than the initial inflammatory target. Bone damage contributes to joint instability and deformity.

D. Surrounding ligaments: Ligament involvement may occur secondarily due to chronic inflammation and joint instability. These structures are not the primary focus of the autoimmune inflammatory process. Ligament damage results from prolonged joint destruction rather than initial pathology.