The adductor magnus is a large muscle located on the inner thigh. As the name suggests, the muscle is one of the largest of the adductor group. It is made up of two portions — the adductor and hamstring portions. The primary action of the muscle is to adduct the thigh although it is also involved in hip flexion. There are several different adductor muscles aside from the magnus including the brevus and longus that work in a similar way.
The hamstring portion of the muscle is also known as the medial portion. This part of the muscle originates from the ischium and descends down to the femur. The hamstring part is a large and soft mass of muscle that is made up of bundles of muscle fibers. Innvervation of the hamstring portion of the muscle is via the sciatic nerve.
The adductor part originates with muscle fibers that are attached to the pubis. From there the fibers run horizontally before attaching to the linea aspera. The innervation of the adductor part of the muscle is via the obturator nerve.
As a muscle the adductor magnus is one of the more powerful in the body. Its main function is to pull the thigh inwards but it also flexes and extends the hip. Both portions of the muscle have different roles to play in movement. The adductor head of the muscle is used to adduct and flex while the hamstring portion is used to extend the hip. For this reason many different activities rely heavily on the muscle functioning correctly.
An example of a daily activity that uses the muscle is getting into a car. Once the first leg is in the adductor magnus is used — along with other adductor muscles — to bring the second leg in with it. Other activities that require adduction will also use the muscle making it important for many sports.
As the adductor magnus is such an important muscle it regularly becomes injured. Generally rest and ice will help to resolve the problem although due to the frequent use of the muscle a complete recovery may take some time depending on the severity of the problem. Injuries to the adductor muscles can generally be avoided by making sure that they are as flexible as possible through daily stretching. Using hip adduction exercises to strengthen the muscle can also help to reduce the risk of injury.