C. Hip Muscles

Primary Hip Flexors

• iliopsoas

• sartorius - combined hip flexion, ER, abduction

• TFL

• Rectus Femoris

• Adductor Longus

• Pectineus

Secondary Hip Flexors

• adductor brevis

• gracilis

• gluteus minimus (anterior fibers)

Primary Hip Adductors

• Pectineus

• Gracilis

• adductor Longus

• Adductor Brevis

• adductor magnus

Secondary Hip Adductors

• LH of Biceps Femoris

• Gluteus Maximus (inferior/posterior fibers)

• Quadratus Femoris

• Obturator Externus

Primary Hip IRs

Don’t have any

Secondary Hip IRs

• gluteus minimus & medius (anterior fibers)

• TFL

• Adductor Longus

• Adductor Brevis

• Pectineus

Primary Hip Extensors

• gluteus maximus

• biceps femoris (LH)

• semitendinosus

• semimembranosus

• adductor magnus (posterior head)

Secondary Hip Extensors

• gluteus medius (middle and posterior fibers)

• adductor magnus (anterior head)

Primary Hip Abductors

• gluteus medius

• gluteus minimus

Secondary Hip Abductors

• piriformis

• sartorius

• rectus femoris

• gluteus maximus (ant/sup fibers)

Primary Hip ERs

• gluteus maximus

• piriformis

• obturator internus

• gemellus superior

• gemellus inferior

• quadratus femoris

Secondary Hip ERs

• gluteus medius & minimus (posterior fibers)

• obturator externus

• sartorius

• biceps femoris (LH)

Internal Snapping Hip Syndrome

Where the iliposoas tendon snaps over the femoral head or anterior pelvis, causing a snapping sensation

Where does Internal Snapping Hip Syndrome most commonly occur?

distal portion of the iliopsoas tendon, especially as it crosses the femoral head or anterior brim of the pelvis

Who commonly experiences Internal Snapping Hip Syndrome?

Dancers and others who perform frequent hip flexion

• mnemonic: West Side Story dancers have internal need to snap and flex their hip

Is Internal Snapping Hip Syndrome always painful?

No, it's often benign unless it becomes painful or disabling

Internal Snapping Hip Syndrome Treatment

• Surgical partial release or

• Tendon lengthening to reduce mechanical irritation.

Psoas Major - Flexor

Origin

Sides of T12–L5 vertebrae and discs between them; TPs of all lumbar vertebrae

Psoas Major - Flexor

Insertion

Lesser trochanter of femur

Psoas Major - Flexor

Innervation

Anterior rami of L1, L2, L3

Iliacus - Flexor

Origin

iliac crest

iliac fossa

ala of sacrum

anterior sacroiliac ligaments

psoas major tendon

lesser trochanter

femur distal to it

Iliacus - Flexor

Innervation

Femoral nerve (L2, L3)

Sartorius - Flexor

Origin

ASIS and superior part of notch inferior to it

Sartorius - Flexor

Insertion

Superior part of medial surface of tibia (as part of pes anserinus)

Sartorius - Flexor

Innervation

Femoral nerve (L2, L3)

TFL - flexor

origin

ASIS

anterior part of iliac crest

TFL - Flexor

iliotibial tract, which attaches to lateral condyle of tibia

TFL - Flexor

N

superior gluteal nerve (L5, S1)

Rectus Femoris - Flexor

O

AIIS and ilium superior to acetabulum

Rectus Femoris - Flexor

I

quad tendon

Rectus Femoris - Flexor

N

Femoral nerve (L2, L3)

may receive a branch from obturator nerve

Pectineus - Adductor

O

superior ramus of pubis

Pectineus - Adductor

I

pectineal line of femur, just inferior to lesser trochanter

pectineus - adductor

N

femoral nerve (L2, L3)

Adductor Longus - Adductor

O

Body of pubis inferior to pubic crest

Adductor Longus - Adductor

I

middle third of linea aspera of femur

Adductor Longus - Adductor

obturator nerve and branch of anterior division (L2, L3, L4)

Gracilis - Adductor

O

body and inferior ramus of pubis

gracilis - adductor

I

superior part of medial surface of tibia (as part of pes anserinus)

Gracilis - adductor

N

obturator nerve (L2, L3)

adductor Brevis - adductor

O

body and inferior ramus of pubis

adductor brevis - adductor

I

pectineal line and proximal part of linea aspera of femur

adductor brevis - adductor

N

obturator nerve and branch of anterior division (L2, L3, L4)

Adductor magnus - adductor

O

adductor part: inferior ramus of pubis and ramus of ischium

hamstring part: ischial tuberosity

adductor magnus - Adductor

I

adductor part: gluteal tuberosity, linea aspera, and medial supracondylar line

hamstring part: adductor tubercle of femur

adductor magnus - adductor

N

adductor part: obturator nerve (L2, L3, L4) and branches of posterior division

hamstring part: tibial part of sciatic nerve (L4)

Gluteus Maximus - extensor

O

Ilium posterior to posterior gluteal line, dorsal surface of sacrum and coccyx, and sacrotuberous ligament

Gluteus Maximus - extensor
I

Most fibers end in the iliotibial tract, which inserts into the lateral condyle of the tibia; some fibers insert on the gluteal tuberosity

Gluteus Maximus - extensor

N

Inferior gluteal nerve (L5, S1, S2)

Biceps Femoris (Long Head)

O

Ischial tuberosity

Biceps Femoris (Long Head)

I

Lateral side of the head of the fibula

Biceps Femoris (Long Head)

N

Tibial division of sciatic nerve (L5, S1, S2)

Anterior Pelvic Tilt force couple muscles

hip flexors and lumbar extensors

How does the anterior pelvic tilt force couple work?

Hip flexors rotate the pelvis anteriorly; back extensors pull in the opposite direction, creating a force couple around the M-L axis.

What muscles create the force couple for posterior pelvic tilt?

hip extensors and abdominals

What limits posterior pelvic tilt?

hip flexors and capsular ligaments

What effect does posterior pelvic tilt have on lumbar lordosis

It reduces lumbar lordosis

Which hip adductor acts as a hip extensor regardless of joint position?

The posterior fibers of the adductor magnus

What happens to the torque potential of most adductors within 40–70° of hip flexion?

Their torque potential decreases

When do the adductors have better leverage for flexion or extension?

Outside of 40–70° of hip flexion

What happens outside the 40–70° arc of hip flexion?

Adductors have better leverage for either hip flexion or extension.

How do adductors behave near full hip flexion?

They are mechanically prepared to extend the hip.

How do adductors behave near full hip extension?

They are mechanically prepared to flex the hip

What happens to internal rotators when the hip is flexed to 90°?

Their torque potential increases due to a longer internal rotation moment arm.

Why do internal rotators become more effective at 90° hip flexion?

Muscles like glute medius and minimus shift from a parallel to perpendicular line of force relative to the AOR, increasing their leverage.

What happens to some external rotators at ~60° of hip flexion?

They switch function and begin acting as internal rotators

Which muscle group is most active in resisting a forward lean in standing?

Hamstrings

Why do hamstrings resist forward lean more than glute max?

Forward lean increases hamstring’s moment arm and decreases glute max’s, making hamstrings more mechanically effective

Why does the nervous system favor hamstrings over glute max during forward lean?

It holds glute max in reserve for powerful extension activities.

Which plane has the greatest overall torque potential at the hip?

Sagittal plane

What is the torque potential order of hip muscle groups from greatest to least?

Greatest to least torque potential:

• Extensors > Flexors (Sagittal)

• Adductors > Abductors (Frontal)

• Internal rotators > External rotators (Horizontal)

ext > flx > add > abd > IR > ER

EFDBIE

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