Which bones increase the efficiency of muscles near a joint and are small and rounded?

Sesamoid bones are specialized types of bones that develop within tendons and are generally small and rounded in shape. Their primary function is to protect tendons from wear and tear, while also enhancing the mechanical advantage of muscles that are adjacent to joints. By doing so, they increase the efficiency with which these muscles can generate force and facilitate movement.

The patella, or kneecap, is the most well-known example of a sesamoid bone, and it plays a crucial role in improving the leverage of the quadriceps muscles, aiding in the extension of the knee. The presence of sesamoid bones can thus contribute significantly to the overall efficiency of joint function and movement.

In contrast, flat bones, short bones, and long bones serve different functions in the body. Flat bones, like the sternum or skull bones, primarily provide protection to internal organs and serve as attachment points for muscles. Short bones, such as those found in the wrists and ankles, offer stability and support while allowing for a limited range of motion. Long bones, like the femur or humerus, are essential for facilitating movement and supporting weight but do not have the specific function of increasing muscle efficiency at joints like sesamoid bones do.