What movements do the hips perform?
extension, flexion, abduction, adduction, medial and lateral rotation
The hip bone is also called?
os coxae & the innominate (“unnamed”) bone
What are the three parts of the coxal bone?
ilium, ischium and pubis - these fuse at the acetabulum
Obturator Foramen is formed by?
Conjuction of ischium and pubis
What makes up the pelvis and what are the three articulations formed?
The pelvis is the bony ring made up by the two os coxae and the sacrum.
The three articulations found within this ring are the
-two sacroiliac joints
-pubic symphysis
What forms the sacroiliac joint?
auricular surfaces of ilium and sacrum form synovial part of the SI joint
What type of joint in the sacroiliac joint?
The sacroiliac joint is actually 2 types of joints:
A synovial joint inferiorly and a syndesmosis joint posteriosuperiorly
What can occur with the sacroiliac joint with age?
It may undergo stenosis (ossify)
Sacroiliac Ligaments?
Ventral and Dorsal Sacroiliac
-thickened regions of the SI joint capsule
Iliolumbar
-from iliac crest to TVP of L5
Interosseus sacroiliac
-syndesmotic portion of the joint (fibrous) between the iliac tuberosity and sacrum
**Sacrotuberous
-sacrum to ischial tuberosity
**sacrospinous
-sacrum to ischial spine, which forms the greater and lesser sciatic foramina
What limitations does the iliolumbar ligament create?
limits rotation and anterior gliding of L5 in relation to the sacrum.
limits side-bending of L5 in relation to the pelvis.
The interosseus ligaments provide stability to the sacrum, how?
downward compression of the sacrum, due to the weight of the upper body cause the interosseus ligaments to pull the ilium bones together to tighten the joint.
Anterior sacral rotation is limited by which ligaments?
sacrotuberous
sacrospinous
interosseus sacroiliac
What is nutation?
Nutation is rotation or tilting of sacrum around axis through interosseus ligaments (horizontal axis - 2nd sacral segment)
Nutation brings the iliac crests together and the ischial tuberosities further apart - this increases the size of the pelvic outlet
Anterior Nutation?
Promontory moves interior and anterior
Coccyx moves superior and posterior
-occurs during birth
(“Nutation” - generally refers to Anterior)
Posterior Nutation?
“Counter nutation” - oppositve of Anterior Nutation
Promontoy moves posterior and superior
Coccyx moves interior and anterior
Intertrochanteric line
separates the neck from the shaft of the femur, anteriorly.
Linea aspera
Ridge on posterior aspect of the femural shaft
Adductor tubercle
small prominence at superior part of the medical epicondyle (tagged on lab exams)
What type of joint is the hip joint?
The hip joint is a ball and socket synovial joint between the head of the femur and the acetabulum of the coxal bone
What connects the hip joint?
Transverse acetabular lig and acetabular labrum (c-shaped cartilage lining) - enlarges the articular surface
Ligamentum teres or ligament of femoral head - from head to transverse acetabular ligament
What are the 3 main ligaments that make up the main stabilizers of the hip joint? What are their actions?
Iliofemoral (the Y ligament of Bigalow) - limits hypertension of femur
Ischiofemoral - reinforces hip capsule posteriorly
Pubofemoral - reinforces hip capsule inferiorly
During extension what do the hip joint capsule ligaments do?
All 3 ligaments wind around the hip joint so that they tighten in extension
pubofemoral ligament helps
limit abduction of the hip
Flexion of the hip is limited primarily by?
The hamstring muscles
Femoral Neck derives blood from?
Medial and lateral circumflex arteries
The femoral head receives blood from?
Medical and lateral epiphyseal arteries
What is another name for the medial epiphyseal artery?
The arter of the ligamentum teres
Not everyone has this
What artery arises from the medial femoral circumflex artery?
the lateral epiphyseal artery
-this is easily disrupted by fracture and dislocation. This can lead to avascular necrosis of the femoral head.
Psoas Major
A: Lateral Flexion of the vertebral column, flexion of the femur from the hip
O: Bodies and TVPs of T12-L5
I: lesser trochanter of femur
N: L1-4
Psoas Minor
A: Weak flexor of the lumbar spine
O: Bodies of T12-L1
I: Pectineal line of the Pubis
N: L1
Iliacus
A: Flex femur
O: Iliac Fossa
I: Lesser trochanter
N: femoral n.
Gluteus Maximus
A: extend, laterally rotate the femur
O: Iliac crest and sacrum/coccyx
I: gluteal tuberosity and iliotibial tract
N: inferior gluteal n. (L5, S1-2)
Gluteus Medius
A: abduct, medially rotate femur, during gait, supports body on one leg while the other leg swings forward
O: dorsal ilium
I: greater trochanter
N: superior gluteal n. (L5, S1)
Gluteus Minimus
A: abduct, medially rotate femur; assists gluteus medius in supporting the body during gait.
O: dorsal ilium
I: greater trochanter
N: superior gluteal n. (L5, S1)
Tensor Fascia Lata
A: abduct, medially rotate, flex femur while keeping knee extended
O: ASIS, anterior Iliac crest
I: Iliotibial tract which extends down to the lateral condyle of tibia
N: superior gluteal n. (L4, 5)
Which two muscles insert onto the iliotibial tract?
Gluteus maximus and the tensor fascia lata
Which muscles are innervated by the superior gluteal nerve?
Gluteus medius, gluteus minimus and tensor fascia lata
Which muscles are considered the Lateral Rotators?
Piriformis, Superior and Inferior Gemelli, Obturator Internus (thick back of CT that splits gemelli), Quadratus femoris, Obturator externus (most deep, won’t see in lab)
Obturator Internus
A: Laterally rotate femur
O: obturator membrane
I: greater trochanter
N: nerve to obturator internus (L5,S1)
Superior and Inferior Gemelli
A: laterally rotate femur
O: ischium
I: greater trochanter
N: nerves to obturator inernus and quadratus femoris (L5,S1)
Quadratus Femoris
A: laterally rotate femur
O: ischial tuberosity
I: quadrate tubercle
N: nerve to quadratus femoris (L5,S1)
Obturator Externus
A: laterally rotate femur
O: obturator membrane (outer)
I: greater trochanter
N: obturator n. (L3,4)
Piriformis
A: abduct, laterally rotate femur
O: anterior sacrum
I: greater trochanter
N: S1,2
Which iliopsoas and gluteal muscles medially rotate and abduct the femur?
tensor fascia lata, gluteus medius, gluteus minimus
piriformis - abducts
Which iliopsoas and gluteal muscles laterally rotate the femur?
piriformis, obturator internus and externus, superior and inferior gemelli, quadratus femoris
iliacus and psoas
Which iliopsoas and gluteal muscles flex the femur?
tensor fascia lata, iliacus and psoas
Which muscle extends the femur?
gluteus maximus
Which muscles are innervated by the sciatic nerve?
hamstrings, 1/2 adductor magnus, muscles of leg/foot
How does the sciatic nerve travel?
L4,5 S1,2,3 rami exit greater sciatic foramen with the piriformis.
It then enters the thigh between the hamstrings and adductor magnus
Dividing into the common fibular and tibial branches
Which muscles are innervated by the superior gluteal nerve?
gluteus medius, gluteus minimus and tensor fascia lata
Where does the superior gluteal nerve exit?
It exits superior to the piriformis
Which muscle does the inferior gluteal nerve innervate?
Gluteus maximus
Where does the inferior gluteal nerve exit?
It exits inferior to the piriformis