HK 302 - lecture 3

LE: hip and pelvis osteology/arthrology; some associated pathology

hip joint

• formed between the acetabulum and head of the femur

• acetabulum is the fusion of the ilium, ischium, and pubic bones

• deep ball-and-socket articulation

• synovial joint capsule

extracapsular ligaments

iliofemoral:

• strongest ligament in the body; the “Y” ligament"; prevents excessive hip extension and adduction

ischiofemoral:

• limits internal rotation

pubofemoral: limits abduction and extension

intracapsular ligament - ligamentum teres

connects the acetabulum to the fovea of the femur

• only stretched when the hip is dislocated

• conduit for foveal artery that supplies blood to femoral head

• aka: the round ligament

hip labrum

• fibrocartilaginous structure that lines acetabulum

• thicker superiorly

• can become damaged and painful with internal rotation of the hip

femur

longest, strongest, heaviest bone in the body; contributes to both hip and knee joints

head (femur)

articulates in the acetabulum of hip bone

neck (femur)

connects head to body

intertrochanteric line (femur)

anterior attachment for iliofemoral ligament

linea aspera (femur)

supracondylar lines

condyles (femur)

distal part of femur; articulate with tibia inferiorly

greater & lesser trochanter (femur)

proximal portion of femur below the neck

• greater is lateral

• lesser is medial

iliopsoas (iliacus and psoas major)

origin

• iliacus: superior 2/3 of iliac fossa

• psoas major: ventral surfaces of the transverse processes of all lumbar vertebrae

insertion:

• iliacus: just distal to the lesser trochanter

• psoas major: lesser trochanter of the femur

action:

• flexes the hip, flexes/anteriorly tips pelvis

• assists with hip lateral rotation

innervation: femoral nerve

hip adductors

pectineus, adductor magnus, adductor longus, adductor brevis, gracilis

pectineus

origin: superior ramus of the pubis

insertion: pectineal line of the femur

action: hip adduction

innervation: femoral and obturator nerves

adductor magnus

origin: inferior pubic ramus, ramus of the ischium, and ischial tuberosity

insertion: medial to the gluteal tuberosity, middle of the linea aspera, medial supracondylar line, and adductor tubercle

action: hip adduction

innervation: obturator and sciatic nerves

adductor longus

origin: anterior surface of the pubis at the junction of the crest and the symphysis

insertion: middle ½ of the medial lip of the linea aspera

action: hip adduction

innervation: obturator nerve

adductor brevis

origin: outer surface of the inferior pubic ramus

insertion: distal 2/3 of the pectineal line and proximal half of the medial lip of the linea aspera

action: hip adduction

innervation: obturator nerve

gracilis

origin: inferior half of the symphysis pubis and medial margin of the inferior pubic ramus

insertion: medial surface of the body of the tibia distal to the condyle

action: hip adduction; assists with hip flexion and medial rotation of the knee

innervation: obturator nerve

sports hernia

• aka: athletic pubalgia

• hip adductor or rectus abdominus avulsion from pubic rami

• different mechanism and structures involved rather than a “regular hernia: groin hernia (sports) vs extrusion of abdominal viscera (reg)

gluteus maximus

origin: posterior gluteal line of the ilium and posterior surface of the sacrum

insertion:

• proximal and superficial fibers blend into the IT band

• deep fibers insert into the gluteal tuberosity of the femur

action: extends and laterally rotates the hip

innervation: inferior gluteal nerve

gluteus medius

origin: external surface of the ilium, superficial to the gluteus minimus

insertion: oblique ridge of the lateral surface of the greater trochanter

action:

• abducts the hip

• anterior fibers assist with medial rotation and hip flexion

• posterior fibers assist with lateral rotation and hip extension

innervation: superior gluteal nerve

trendelenburg gait

weakness in gluteus medius leads to:

• uncompensated pattern with opposite hip drop

• compensated pattern with same side trunk lean

gluteus minimus

origin: external surface of the ilium between the anterior and inferior gluteal lines

insertion: anterior border of the greater trochanter

action: abducts, medially rotates the hip; assists with flexion (minimal)

innervation: superior gluteal nerve

piriformis

origin: pelvis surface of the sacrum between the first and fourth pelvic sacral foramina

insertion: superior border of the greater trochanter

action: hip lateral rotation; assist in hip extension

innervation: sacral plexus

piriformis syndrome

• numbness and tingling down leg

• more common in females than males

• treatment includes rehabilitation, medication, surgery in extreme situations

*piriformis is typically superficial to sciatic nerve - in around 20% of population, sciatic nerve pierces the piriformis muscle

quadratus femoris

origin: proximal part of the lateral border of the tuberosity of the ischium

insertion: proximal part of the quadrate line

action: hip lateral rotation

innervation: sacral plexus

obturator internus

origin: internal surface of the obturator foramen

insertion: medial surface of the greater trochanter proximal to the trochanteric fossa

action: hip lateral rotation

innervation: sacral plexus

obturator externus

origin:

• external surface of the pubic and ischial rami

• outer surface of obturator membrane

insertion: trochanteric fossa of femur

action: hip adduction and lateral rotation

innervation: obturator nerve

gemellus superior

origin: external surface of the spine of the ischium

insertion: medial surface of the greater trochanter of the femur

action: hip lateral rotation

innervation: sacral plexus

gamellus inferior

origin: proximal part of the ischial tuberosity

insertion: with the tendon of the obturator internus into the medial surface of the greater trochanter

action: hip lateral rotation

innervation: sacral plexus

role of lateral hip rotators at knee and foot

• control of internal and external rotation at the hip will impact the amount of varus and valgus stress at the knee

• common to see lateral rotators not working well and allowing internal rotation