The adductor group of muscles
The adductors are a group of muscles, as the name suggests, that primarily function to adduct the femur at the hip joint. Although they are all located somewhere along the medial side of the thigh, they originate in different places at the front of the pelvis. Most of them are surprisingly thin muscles. The exception to that is the largest of them the, adductor magnus muscle, which we covered in a previous post. The adductor group includes the following muscles:
- Adductor brevis
- Adductor longus
- and the Adductor magnus
What can we learn about the adductor muscles from their names?
Adductor brevis and adductor longus
There are three muscles in this group whose names start with the word, adductor. We’ve covered adductor magnus in a previous post, so we’ll just take a look at adductor brevis and adductor longus.
The word adductor describes the action of these muscles and it comes from the Latin words “ad”, which means “toward” and “ducere”, which means “to lead”. The second word in these two muscle names refers to the size of the muscle. The word brevis is a Latin word meaning short and the word longus is a Latin word meaning long. So, you could put the words together to get an understanding of the size and action of each muscle. Adductor brevis is “a short muscle that leads something toward the body” and adductor longus is “a long muscle that leads something toward the body”.
The gracilis muscle is also included in the adductor group of muscles. Gracilis is the Latin word for slender, so you can see that its name describes its shape. Gracilis is the most medial of the adductors. In addition to the hip, it also affects the knee joint.
This is the last of the muscles that we’ll look at in the adductor group.
Pectineus comes from the Latin word “pecten” which means comb and its name describes its location. The bone that is now referred to as the pubic bone was previously known as the “os pecten” or “comb bone” due to its shape. The pectineus muscle is the most anterior of the adductor group.
Where do the adductor muscles attach?
The adductors are layered muscles that fan out from the small area of attachment on the pubic bone toward the femur. Let’s start with pectineus.
Origin of pectineus
The pectineus originates on the ramus of the pubis.
Insertion of pectineus
It inserts between the lesser trochanter and the linea aspera.
Origin of adductor brevis
The adductor brevis muscle originates on the inferior ramus of the pubis.
Insertion of adductor brevis
It inserts on this area of the linea aspera.
Origin of adductor longus
It originates on the anterior pubis.
Insertion of adductor longus
It inserts on the linea aspera.
Origin of gracilis
Gracilis is the most medial of the adductors. Specifically, it originates on the anterior pubis.
Insertion of gracilis
It inserts on the pes anserine. This is the second of three muscles that attach onto this spot.
What actions do the adductors do?
- You’ll find that pectineus assists in both adduction and flexion of the femur at the hip joint.
- The primary function of adductor brevis is adduction of the thigh at the hip joint. Additionally, adductor brevis assists in flexion and medial rotation of the femur at the hip joint.
- Primarily, the action of adductor longus is adduction of the thigh at the hip joint. It also assists in flexion and medial rotation of the femur at the hip joint.
- The primary action of gracilis is adduction of the thigh. It also assists in flexion of the knee and medial rotation of that flexed knee, similar to what we’ll see when we look at sartorius.