The adductor longus is a muscle located toward the top of the inner thigh. It is situated directly in front of the adductor brevis — a smaller muscle of the same group. The purpose of the adductor longus and other muscles of the adductor group is to adduct or pull the thigh inwards. This means that these muscles are a vital part of many daily activities such as walking. As a group the adductor muscles are commonly referred to as the groin muscles when used to discuss sporting injuries.
Insertion of the adductor longus is around the middle of the femur and hence the muscle has a major role to play in stability of the leg. It originates at the pubis bone. Aside from adduction, the adductor longus also flexes the thigh near the hip and rotates it in some cases. For this reason, an injury to the muscle can cause discomfort in a range of activities.
The adductor longus is one of five muscles in the adductor group. The others are the adductor brevis, pectineus, gracilis and adductor magnus. The adductor brevis — a triangular muscle located just behind the adductor longus — is the most closely associated. Together these two muscles are sometimes known as the long and short adductors.
Of all the muscles in the adductor group, the long adductor is most likely to be injured. An injury to the muscle can take the form of a tear or rupture and is most likely to occur during sport. This is because the muscle is put under an increased amount of strain during sprinting and fast changes of direction. In some cases, repetitive overuse of the muscle can also cause issues such as adductor tendinitis. Due to the important nature of the muscle these conditions can be difficult to treat and require rest and patience to fully heal.
There are three grades of adductor muscle strain. Grade 1 symptoms include mild discomfort in the area along with a feeling of tightness. At this stage problems usually only arise during sporting activity. Grade 2 groin strains, on the other hand, are more serious and involve sharper pain and an increased level of tightness. The person may also feel weakness in the muscle.
Grade 3 groin strains are the most severe and cause the most pain. If a person has a grade 3 adductor injury, he or she will be unable to pull the leg inwards. There will also be a high level of swelling.