Hip and Gluteal Region Flashcards
What is the acetabulum?
An incomplete ring of bone formed by the intersection of the ilium, ishium, and pubis at the triradiate cartilage
What completes the circle created by the acetabulum?
The transverse acetabular ligament
What is the acetabular foramen?
An opening formed between the ligament and the central acetabular fossa
The acetabular fossa houses a
Fat pad
The weight of the body is borne by articular cartilage on the ___ surface of the acetabulum
Lunate
What is the acetabular labrum and what does it do?
It is a ring of fibrocartilage that projects beyond the bony rim of the acetabulum
It helps improve the fit of the femoral head into the acetabulum
What is the structure of the synovial membrane?
It attaches around the head of the femur and extends down the neck of the femur and then reflects back to the rim of the acetabulum
What is the function of the synovial membrane?
It can bunch up and stretch out to accomodate the large range of movement of the femur
What is the structure and function of the zona orbicularis?
It is located in the fibrous joint capsule of the femur and wraps around the neck of the femur
It is smaller in diameter than the head of the femur, so it promotes joint stability
What accomodates the movement of the femoral head within the acetabulum?
Synovial folds
What is the purpose of the ligament of the head of the femur?
It limits the range of motion of the hip joint, but NOT through tension
What is the consequence of the ligament of the head of the feur being too thick to fit between the femoral head and acetabulum?
The range of motion of the hip joint is limited to the area defined by the central fat pad
What elements of the pelvis is the femur bound to?
Ilium
Ishium
Pubis
What ligaments attach the femur to the bones of the pelvis?
Iliofemoral
Pubofemoral
Ishiofemoral
The iliofemoral ligament attaches on the
anterior surface of the femur, along the intertrochanteric line
The pubofemoral ligament attaches on the
inferior aspect of the femoral neck
The ischiofemoral ligament attaches on the
Superior aspect of the femoral neck, continuing to the upper part of the intertrochanteric line
What happens to the femur-pelvis ligaments when a person is standing?
The ligaments are twisted, which exerts a force that pulls the head of the femur firmly into the socket formed by the acetabulum
What happens to the head of the femur when standing?
How is this corrected?
Part of the articular cartilage on the head of the femur is exposed on the anterior and superior aspect of the articular ball
To bring the articular surface into contact with the acetabulum requires flexing and abducting the femur
What is the true physiological position of the hip?
When the femur is flexed and abducted
The ligaments around the head of the femur are laxed when the hip is
Flexed
What happens to the ligaments of the hip when someone is in the seated position?
The ligaments are lax, which makes the hip joint particularly susceptible to posterior dislocations
Dislocations of the femur are prevalent ANTERIORLY between the
Iliofemoral and pubofemoral ligaments
Dislocations of the femur are prevalent POSTERIOLY between the
Iliofemoral and ishiofemoral ligaments
Parts of the femur/hip joint from deep to superficial
Acetabular membrane (located inside the synovial membrane)
Synovial membrane is inside the fibrous capsule of the joint (contains the zona orbicularis)
Fibrous capsule of joint is inside the tube of ligaments that bind the femur to the hip (iliofemoral, ischiofemoral, and pubofemoral ligaments)
These ligaments are surrounded by the muscles of the hip
The muscles of the hip are covered by fascia lata
Fascia lata is covered by subcutaenous fat and skin
What supplies the acetabulum?
Obturator atery- anterior and posterior branches
Blood is supplied to the femoral head by
Lateral femoral circumflex artery
Medial femoral circumflex artery
Both the lateral and medial femoral circumflex arteries branch from or near the
Profunda femoris artery
What are the two anastomoses of the lateral and femoral circumflex arteries
Circulate anastomosis that occur around the femur, below the greater troachanter
Both also give off ascending branches that anastomose around the femoral neck
What supplies the acetabulum?
Acetabular branches of the posterior obturator artery
What is fascia lata?
Outer layer of the deep fascia over the thigh
Fascia lata is anchored superiority in a ring that includes
Inguinal ligament
Iliac crest
Sacrum
Coccyx
Sacrotuberous ligament
Pubis
Fascia lata is inferiorly continuous with
Deep fascia of the leg (fascia cruris)
What is the iliotibial tract/band?
It is the thickened, lateral aspect of the fascia lata
The iliotibial tract/band is attached superiorly to
The tubercle of the crest of the ilium
The iliotibial tract/band is attached inferiorly to
The proximal part of the tibia
What is the function of the iliotibial tract?
To reduce bending load on the femur
Function of tensor fasciae lata
Stabilizes knee in extension
The obturator externus is innervated by
Obturator nerve, posterior division
Tensor fascia lata is innervated by
Superior gluteal nerve
Gluteus maximus is innervated by
Inferior gluteal nerve
Gleuteus medius and gluteus minimus are innervated by
Superior gluteal nerve
Piriformis muscle is innervated by
Nerve to piriformis
Obturator internuis is innervated by
Nerve to obturator internus
Superior gemellus is innervated by
Nerve to obturator internus
Inferior gemellus is innervated by
Nerve to quadratus femoris
Quadratus femoris is innervated by
Nerve to quadratus femoris
Femoral nerve and its sidekicks innervated
Iliacus and psoas
Common fibular sidekicks are
Gluteal nerves
Tibial nerve and its sidekicks innervate
Lateral rotators
Posterior division of obutrator nerve comes from
L3-L4
Superior gluteal nerve that innervates tensor fascia lata comes off
L4-S1
Inferior gluteal nerve that innervates gluteus maximus comes off
L5-S2
Superior gluteal nerve that innervates gluteus medius and minimus comes off
L5-S1
Nerve to piriformis comess off
S1-S2
Nerve to obturator internus comes off
L5-S2
Nerve to quadraus femoris comes off
L4-S1
Sidekicks to common fibular nerve include
Superior gluteal nerve
Inferior gluteal nerve
Nerve to piriformis
Sidekicks of tibial nerve include
Nerve to obturator internus
Nerve to quadratus femoris
Dorsiflexion (extension) of upper foot is done by
L4-S1 (common fibular)
Extension of upper leg is done by
L2-L4 (Femoral nerve)
Flexion of upper thigh done by
L1-L2 (Femoral nerve)
Flantarflexion (flexion) of bottom foot is done by
L4-S5, S1-S2 (Tibial nerve)
Flexion of bottom of leg done by
L5-S2 (Tibial nerve)
Extension of bottom thigh done by
L5-S2 (Common fibular)
What defines the inferior border of the buttock
Gluteal/natal fold
The most superficial muscle in the superior-lateral region of the buttock is the
Gluteus medius
Where does the gluteus maximus insert?
Deep distal 1/4 inserts on the femus
Remainder inserts on IT tract
Function of the gluteus maximus
Powerful extensor of flexed thigh
Laterally stabilizes hip and knee via IT tract
Laterally rotates and abducts thigh
Overall function of small glutes
Abduct femur
Pervents pelvic tilt
What do the anterior part of small glutes do?
Flex and internally rotate thigh
What do the posterior parts of the small glutes do?
Extend and laterally rotate thigh
What runs above the piriformis?
Superior gluteal artery, vein, and nerve
What runs below the piriformis?
Inferior gluteal artery, vein, and nerve
Sciatic nerve
Posterior femoral cutaneous nerve
Arterial supply to the pirifromis may include
Superior and inferior gluteal arteries
Lateral sacral artery
Circulate anastomosis involves ___ superiorly
Inferior gluteal artery
Circulate anastomosis invovles __ mediolaterally
Lateral and medial femoral circumflex arteries
Circulate anastomosis invovles ____ inferiorly
First perforating branch of the profunda femoris artery
What are the bursae of the hip?
Ischial bursae
Trochanteric burase
Gluteofemoral bursa
Ischial bursae separates
gluteus maximus from ischial tuberosity
Trochanteric burase separates
gluteus maximus from greater trochanter
Gluteofemoral bursa separates
IT tract from proximal attachment of hamstrings
What are the lateral rotators of the hip?
Piriformis
Obturator internus
Gemellus superior
Gemellus inferior
Quadratus femoris
Origin of piriformis
Anterior surface of sacrum
Origin of obturator internus
Deep surface of obutrator membrane and surrounding bone
Gemellus inferior origin
upper aspect of ischial tuberosity
Gemellus superior origin
External surface of ischial spine
Where do the piriformis, obutrator internus, gemellus supeior, and gemellus inferior insert
On greater trochanter of femur
What is the overall function of the piriformis, obturator internus, gemellus supeior, and gemellus inferior?
Laterally rotate extended femur
Abduct flexed femur
Origin of quadratus femoris
Lateral aspect of ischium
Insertion of quadratus femoris
Quadrate tubercle on intertrochanteric crest
Action of quadratus femoris
Strong lateral rotator of femur
Fibers of the obturator internus exit the pelvis through
Lesser sciatic foramen
What forms the lesser sciatic foramen?
Lesser sciatic notch
Sacrospinous ligament
Sacrotuberus ligament
Obutrator externus originates from
External surface of obturator membrane
Obturator externus inserts into
Trochanteric fossa
What is the function of obturator internus?
Laterally rotates thigh
What innervates the obturator externus
Obturator nerve
Sensory innervation of the buttock is done by
Cluneal nerves
Lateral branch of iliohypogastic nerve
What is the source of the superior and middle cluneal nerves?
Dorsal rami of the lumbar and sacral vertebrae
What is the source of the inferior cluneal nerve
Posterior femoral cutaneous nerve
Perforating cutaneous nerve overlaps with the
Posterior cutaneous nerve of the thigh
Perforating cutaneous nerve innervates
Skin over the medial aspect of the gluteal fold
Perforating cutaneous nerve is derived from
S2-S3
Perforating cutaneous nerve leaves the pelvic cavity by
Penetrating directly through the sacrotuberous ligament, after which it passes inferiorly around the lower border of the gluteus maximus
What is sciatica?
Symptoms of pain in the lower back, gluteal region, thigh, or leg
It caused by compression/irritation of sciatic nerve
What is piriformis syndrome?
Irritation of sciatic nerve by piriformis muscle
What are the extensors of the hip?
Gluteus maximus
What are the abductors of the hip?
Small glutes
What are the lateral rotators of the hip
Piriformis
Obturator internus
Gemelli
Quadratus femoris
