Thigh Muscles

What are the thigh muscles?

The thighs contain some of the largest muscles in the body. The thigh muscles allow the lower body to bend, flex and rotate. They also bear most of the body’s weight, and keep the hips and legs aligned, in addition to providing and assisting with balance.

Thigh muscles can be grouped based on their function and location:

• Adductors.
• Hamstrings.
• Pectineus.
• Quadriceps, often called the quads.
• Sartorius.

What is the purpose of the thigh muscles?

Each group of muscles in the thigh has a different job:

• Adductors: Allow you to bring the thighs toward each other, which is called adduction. They help you stay balanced, keep the legs and hips in alignment, and allow rotation through the hips and legs.
• Hamstrings: Allow you to extend (tilt) your hip to move your leg behind your body, such as when you walk and put one leg behind you. They also let you flex (bend) your knee, like when you squat.
• Pectineus: Enables you to flex and rotate the thigh at the hip joint. It also helps stabilize the pelvis.
• Quadriceps: Allow you to flex your hip (for example, squatting or sitting) or extend the knee (standing or reaching the leg straight in front of you to take a step).
• Sartorius: Helps you flex and rotate the thigh from the hip joint. You use it when you cross your legs to rest one ankle on the opposite leg. Other examples include sitting cross-legged on the floor or bending and rotating your leg to look at the bottom of your foot.

Where are the adductors, hamstrings, pectineus, quadriceps and sartorius located?

• Adductors include five muscles: gracilis, obturator externus, adductor brevis, adductor longus and adductor magnus. They are on the inside of the thigh, starting at the pelvis and extending to the femur (thigh bone).
• Hamstrings are a group of three muscles: semitendinosus, semimembranosus and biceps femoris. They run down the back of the thigh, from the hip to just below the knee.
• Pectineus is a flat muscle that extends from the front of the pelvis to the top of the femur.
• Quadriceps include four large muscles located in the front of the thigh: vastus lateralis, vastus medialis, vastus intermedius, and rectus femoris. They start at the pelvis (hip bone) and femur (thigh bone) and extend down to the patella (kneecap) and tibia (shin bone).
• Sartorius muscle is a long, thin muscle — the longest in the human body. It starts by the hip and wraps across the front of the thigh, then downward toward the knee.

What are the thigh muscles made of?

The thigh muscles are skeletal muscles. They attach to bone with tendons, and they help move parts of the skeleton.

They’re made of bundles of muscle fibers containing blood vessels and nerve fibers. All of the components are held together with connective tissue.

These muscles are very elastic, so they can stretch a lot.

What conditions can affect the thigh muscles?

The most common problems in the thigh muscles are muscle strains, pulls and tears. This type of injury occurs when a muscle is stretched beyond its limits and the muscle fibers pull apart.

Strains are common in the hamstrings and quads. They often occur during sports or other exercise where a person has to change direction quickly, or they collide with something or someone. Examples include soccer and football.

Symptoms of a thigh muscle strain include:

• Bruising that develops quickly or over the next couple of days following an injury.
• Pain, which usually is sudden and severe, and may get worse when you bend or extend the hip or knee.
• Popping or snapping sound or feeling in the thigh.
• Swelling.

How can I keep my thigh muscles safe and healthy?

You can take steps to keep your thigh muscles safer and healthier, especially during exercise:

• Avoid sports that involve changing direction quickly or tackling.
• Don’t “play through the pain.” If something hurts, stop and rest.
• Eat a healthy diet high in protein.
• Exercise often. The stronger your muscles are, the less likely they are to become injured.
• Maintain a healthy weight to reduce pressure on the muscles.
• Stay hydrated by drinking lots or water.
• Warm up before you exercise, increase intensity gradually, then stretch afterward.
• Wear shoes that fit well and all appropriate safety equipment for any sports you play.

When should I call a healthcare provider about thigh muscle problems?

Damage to a thigh muscle can increase the chances that you’ll injure yourself even more. Talk to a healthcare provider if you have:

• Inability to bend or extend the hip or knee.
• Loss of feeling or persistent weakness in the thigh or hip.
• Pain that doesn’t go away or gets worse when you bend or extend your hip or knee.
• Popping or snapping noise in the leg.
• Repeated injuries.
• Swelling or bruising.
• Trouble putting weight on your leg.

A note from Cleveland Clinic

The thighs contain many muscles that control movement of the hips and legs. The main types are the adductors, hamstrings, pectineus, quadriceps and sartorius. Thigh muscle injuries are common, especially strains, pulls and tears in athletes. Call your healthcare provider if you have pain, numbness or weakness, or any trouble putting weight on your leg.