Iliacus

ILIACUS

The iliacus muscle is shaped like a triangle, flat and an exact fit of the iliac fossa — the curved surface of the largest pelvic bone. Together with the psoas major muscle, it is also called the iliopsoas muscle.

ANATOMY

Origin

Upper 2/3 of iliac fossa of ilium, internal lip of iliac crest, lateral aspect of sacrum, ventral sacroiliac ligament, and lower portion of iliolumbar ligament

Insertion

Lesser trochanter of femur. Its fibers are often inserted in front of those of the psoas major and extend distally over the lesser trochanter.

Nerve supply

The iliacus muscle is supplied with nerves by the branches of the second and third nerves of the lumbar area through the femoral nerve.(L2,L3)

Artery

Lumbar branch of iliopsoas branch of internal iliac artery

Action

• The iliacus muscles flexes and externally rotates the femur.
• It is also one of the key muscles that helps to maintain proper body posture.
• When combined with the psoas muscle the two muscles are considered the strongest hip flexors in the body.
• It is also one of the key muscles that helps to maintain proper body posture.
• The Iliacus muscle can also add to an anterior tilt of the pelvis (down and forward).
• Just like the iliacus, the iliopsoas is responsible for hip flexion. This muscle is also involved in trunk flexion, which is bending the trunk forward such as when you perform a sit-up or bend down to tie your shoes.

ILIACUS DYSFUNCTION

Excessive use of the muscle can make it shorter, especially if someone does desk job each day. This muscle can also become shorter through lots of exercising without stretching. As this muscle shortens, it can start to cause dysfunction and injuries in the hip and pelvic regions of the body, such as:

• Trigger points - tight areas or knots in the iliacus muscle that are painful, tender, and stiff.
• Iliacus ischemia - a condition of reduced blood flow to the muscle.
• Hip, knee, and lower back problems - If the iliacus on one side of the hip becomes shorter than the iliacus on the other, this can cause a person to walk with imbalanced hips, affecting the normal gait of a person. (Try walking while keeping one hip lower than the other, you will probably start to feel pain and irritation in your hips, knees, and lower back)

The main symptom of iliacus dysfunction is pain. This pain can be in the hips, groin, lower back, and upper thigh regions of the body. Other symptoms include:

• Stiffness
• Decreased range of motion
• Tenderness