Muscles, tendons and bone comprise units. These units stabilize the hip joint and allow its motion. A strain occurs at the weakest part of a unit. There is no loss of strength. Strength is diminished.
Severe strain requires surgical repair.
Chronic strains are caused by overuse. Acute strains are caused by direct injury or overstress. Trochanter of the femur. Muscles or tendons that attach to the trochanter. Pain when moving, stretching or twisting.