Hip

What nerves innervate the hip joint? (bring back sensory info)

femoral nerve and obturator nerve

Name the ligaments of the hip

iliofemoral pubofemoral ischiofemoral

The acetabulum is made up of what bones?

ilium, ischium, and pubic bones

True or False: NO ligaments of the hip joint attach to the back of the femur

True

True or False: the acetabulum projects inferiorly, anterior, and laterally

true

True or false: most of the blood suppy to the femoral head and neck is posterior

true

if the torsion angle is greater than 15 degrees, what occurs?

"toe in" walking; *excessive anteversion*

Describe the torsion angle

-"twisting of the neck in relationship to the rest of the shaft of the femur" -angle between the transverse axis of the femoral condyles and the axis of the femoral head and neck -normally 10-15 degrees anteverted (femoral head naturally points anteriorly)

Describe the iliofemoral ligament

-Y ligament of Bigelow -extends from anterior inferior iliac spine and anterior superior rim to the intertrochanteric line -*strongest* -prevents extension, and the upper fibers prevent ER

Describe the ischiofemoral ligament

-extends from posterior inferior rim to the apex of the greater trochanter -spirals anteriorly -partly covers neck -prevents extension and internal rotatoin

Describe the joint capsule of the hip joint

-extends from the acetabular rim to intertrochanteric line anteriorly -posteriorly: arched border cross anteriorly -synovial membrane protrudes posteriorly and acts like a bursa (obturator externus bursa)

Describe the pubofemoral ligament

-extends from the anterior inferior rim and the superior pubic ramus to the intertrochanteric line -deep to iliofemoral, covers neck of femur -prevents abduction, little external rotation, and extension

What is the angle of inclination of the hip?

-in the frontal plane, the angle of inclination is between the femoral neck and shaft. -normally *125/126 degrees* -at birth, 140-150 degrees

Describe the blood supply to the femoral head and neck

-obturator artery has an acetabular branch that runs through the ligamentum teres (minor supply to hip; more important in early development) -the deep femoral artery has a medial femoral circumflex artery and the ascending branch of the lateral femoral circumflex artery (majority of blood for hip) -retinacular arteries from the medial and lateral femoral circumflex arteries run parallel to the femoral neck

Describe coxa valga

-valga = bend outward -angle of inclination is >125 degrees

Describe coxa vara

-vara = "bend inward" -angle of inclination is <125 degrees

Approximately how much of the femoral head fits in the acetabulum

1/2

Describe what happens to the articular capsule in hip extension

In hip extension, the articular capsule is pulled taut (increases spiral), pulling the head of the femur into the acetabulum (this is why we have limited ROM in extension)

What is the labrum? What does it do?

Labrum is fibrocartilage lip on the rim of the acetabulum that deepens the socket and therefore increases stability. It is not a complete circle.

Describe the ligamentum teres

The ligamentum teres comes out of the acetabular notch and goes to the fovea on the head of the femur. *It provides little ot no stability for the hip joint*. It holds a branch of the obturator artery.

What is the transverse acetabular ligament?

a ligament that connects the labrum over the acetabular notch (where the labrum is incomplete)

Infants have how many degrees of anteversion?

about 30 degrees anteversion...this decreases by 6 years old

What ligaments and muscles increase the stability of the hip joint the MOST?

anterior ligaments (iliofemoral), and lateral rotators posterior to the joint

"spiraling" of the hip ligaments occurs during hip extension or hip flexion?

hip extension

Name the muscle tendon and the ligament that cover the posterior femoral neck

obturator externus tendon ishciofemoral ligament cover the posterior femoral neck

If the torsion angle is less than 15 degrees, what occurs?

retroversion

If the acetabular projects laterally OR postero-laterally, it is considered to be _________

retroverted

What kind of joint is the hip joint?

synovial - ball 'n socket

What is the acetabular anteversion angle?

the extent the acetabulum projects anteriorly; usually 15-20 degrees anteverted; this exposes the anterior head of the femur covered by capsule and muscle tendon (what muscle)?

Why does the angle of inclination shrink after birth?

weight of the body on the femoral neck pushes it downward