The musculoskeletal system is organized to optimize mobility to varying degrees throughout the animal kingdom. Muscles are attached to bones by their tendons and bones articulate with other bones at their articulating ends by the numerous ligaments.  At some points these ligaments span from one area to another while contributing to the formation of joint capsules at the respective junction. The upper limb is the most mobile appendage of the human body. It can achieve a vast range of motions and also facilitates the completion of fine motor tasks.