HW #9 The Hip & Pelvic Joint

Explain the similarities and differences between the gluteus maximus, gluteus minimus and the gluteus medius.

differences: vary in size, glute max is posterior (hip ext, external rotation, upper fibers = abduction, lower fibers = adduction) glute minimus = anterior (abduction, hip flexion, internal rot), glute medius = lateral (hip flexion/extension, can assist w/ internal & external rot)

t/f: hip flexion and extension occur in the frontal plane of motion if false: correct the statement

false; both occur in sagittal plane

t/f: leg lifts concentrically work the abdominal muscles if false: correct the statement

false; leg lifts isometrically contract the ab muscles

t/f: the gracilis is the muscle working while sitting "crisscross applesauce." if false: correct the statement

false; sartorius

t/f: The gluteus maximums is commonly used to extend the hip in ordinary walking. if false: correct the statement

false; the hamstrings are the walking muscles; the pelvis & femur must exceed 16 degrees during extension to call on gluteus maximus

Describe the similarities and differences between the illiacus, the psoas major, and the psoas minor

-psoas major & minor have same OG but different IN -iliacus & psoas major have same IN points -psoas minor does not act on hip

What is the error many people make while working their hamstrings?

1) only do one exercise or stretch - you need to do 2 (bi-articulate insufficieny: some people try to flex the knee and hip @ same time to work hamstrings)

What are the 3 reasons the hip joint is so stable?

1.bony architecture 2. strong ligaments 3. large supportive muscles

What is the longest muscle in the body?

Sartorius

What is the best way to stretch the iliopsoas?

a lunge; "extend the hip where the femur is behind the plane of the body (avoid knee flexion)

Muscles that flex the hip usually_____________ rotate the pelvis, and muscles that extend the hip usually_____________ rotate the pelvis.

anteriorly; posteriorly

What are the functions of the labrum?

enhance stability & provide shock absorption

What kind of joint is the hip? The pubis?

hip = acetabular femoral pelvis = amphiarthrodial

What is the main job of the tensor fasciae latae?

hip abduction (directs leg forward in walking/running)

Why is it important to stretch the hip flexors/hip extenders (beyond the basic reasoning behind the need for lengthening a muscle after you shorten it).

if they are too tight, it can lead to low back pain

Why do men more commonly pull their groin?

men less commonly exercise their inner thighs/groin/adductors (pectineus) -lack flexibility in groin

What purpose do the abdominal muscles have in regulating the orientation of the pelvis?

isometrically contracting the abs holds the pelvis in neutral position

How is the adductor magnus different from all the other adductors?

it helps extend the hip as well as flex it

How does the gracilis differ from all the other adductor muscles?

it's bi-articulate & adds weak assistance to knee flexion

Which quad muscle suffers from bi-articulate insufficiencies?

rectus femoris

What are the similarities between all 3 hamstrings? What are the differences?

similarities: they all OG on ischial tuberosity, all 2-joint muscles (cross hip & knee), all do hip extension (& posterior pelvic rotation) & knee flexion differences: bicep femoris has 2 heads, insert on different areas around tibia ( semi's do internal rotation, bicep fem does external rotation)

Why do we NOT describe the hip as having the specific motions of horizontal adduction (flexion) and abduction (extension)?

there are not specific muscles in the hip joint that do these actions like we do in the shoulder -the muscles in hip joint just perform abd/adduction just do it in another plane - not specifically horizontal abd/adduction

In what plane of motion do hip internal and external rotation occur?

transverse plane

t/f: The tensor fasciae latae is important in helping direct the leg forward so that the foot is placed straight forward in walking and running. if false: correct the statement

true

t/f: the gracilis is the only 2-joint adductor if false: correct the statement

true