Lower Ext 1

Lower limb has 30 bones

** TEST QUESTION Sartorius is also called Tailor’s
muscle

locomotion and balance

1. Femoral region (thigh)
2. Knee and leg region (between the knee joint and ankle joint)
3. Ankle Region (tarsal bones)
4. Foot

Gluteus maximus = cheeks

Natal/ gluteal cleft = crack

Gluteal folds = bottom of cheek

• Sartorius (lateral)
• Adductor longus (medial)
• Inguinal ligament
(superior)

Femoral nerve

-Bony ring of sacrum and right and left hip bones
-Joined at pubic symphysis

Sesamoid bone

Quadraceps fermoris and the knee joint capsule

Tendons

Tibia

Fibula

Does NOT do pronation or supination

Talus = ankle. Found between the tibia and fibula. Articulates with both.

Calcaneus = heel. Attachment for Calcaneal tendon. Carries the talus.

The matatarsals are homologous to the metacarpals

Band of connective tissue

Superficical fascia is attached to the dermis of skin

Deep fascia forms the intermuscular septa

Superfical fascia is made of areolar tissue with fat. It determines the shape of the body. It surrounds organs, glands, and neurovasular bundles. It also conserves body heat

Fascia lata

Pelvis and inguinal ligament

The thickened ILIOTIBIAL TRACT

The gap in front of the thigh and below inguninal ligament is called the Saphenous opening

1. Great saphenous vein
2. Small branches of femoral artery
3. Lymph vessels

The falciform margin. Lies anterior to femoral vessels

Cribriform fascia

Proximal region of femoral triangle

1. Anterior abdominal wall below umbilical
2. Lower anal canal
3. External genitalia

1. Buttox
2. Back below iliac crest

The great saphenous vein is formed by the dorsal venous arch
of the foot, and the dorsal vein of
the great toe

The great saphenous vein It ascends up the medial side of
the leg, passing anteriorly to
the medial malleolus at the ankle,
and posteriorly to the medial
condyle at the knee

The great saphenous vein terminates by
draining into the femoral vein
immediately inferior to the inguinal
ligament

Surgically, the great saphenous vein
can be harvested and used as a
vessel in coronary artery bypasses.

Iliopsoas, rectus femoris, sartorius. Adductor muscles

Gluteus maximus, hamstrings

Gluteus medius and minimus, sartorius, tensor fascia
lata, piriformis, upper fibers of gluteus maximus

Adductor muscles, pectineus, gracilis

Piriformis, obturator internus and externus, superior
and inferior gemelli, quadratus femoris, gluteus
maximus

Anterior fibers of gluteus medius and minimus, tensor
fascia lata

All are needed

1. Gulteus maximus
2. Gluteus medius
3. Gluteus minimus
4. Tensor fasia lata

The gluetus medius, gluetus minimus, and tensor fascia lata are all supplied by the superior gluteal nerve (L4-S1). The gluetus maximus is supplied by the Inferior Gluteal nerve (L5-S2).

Extension, lateral
rotation, abduction.
Climbing, running
rising from sitting
position

Abduction, medial
rotation. Tilts the pelvis
when walking

Abduction, medial
rotation

Flexion and medial
rotation. Tenses the
fascia lata

O: Iliac crest, ASIS
I: Iliotibial tract

1. Piriformis
2. Superior gemellus
3. Obturator internus
4. Obturator externus
5. Inferior gemellus
6. Quadratus femoris

Ventral rami of S1, S2
(sacral plexus)

Sacral plexus (L5-S2)

Sacral plexus (L5-S2)

Posterior branch of
obturator nerve (L2,3,4)

Nerve to the quadratus
femoris (L4-S1

Nerve to the quadratus

Lateral rotation

Piriformis and Obturator Internus

Obturator Externus

The glut maximus is the extensor of the thigh

The glut medius does pelvic tilt relative to insertion when foot is planted

The major lateral rotator is the Piriformis.

1. Psoas major
2. Iliacus
3. Iliopsoas
4. Sartorius
5. Quadriceps femoris (4 muscles)
6. Articularis genus

Lumbar plexus (L2, L3)

Flexion of the thigh;
flexion of the trunk
*****sitting up from lying
down position

Femoral nerve

Flexion of the thigh/trunk

L1-L3 and part of femoral nerve

***Chief flexor of the thigh. Advance limb when walking

Femoral nerve (L2,3,4)

Flexion, abduction and
lateral rotation of the
thigh. Flexion and
medial rotation of the
leg

Femoral nerve (L2, 3, 4)

1. Rectus femoris
2. Vastus Lateralis
3. Vastus Medialis
4. Vastus Intermedius

Extension of the leg and flexion of thigh

1. Pectineus
2. Gracilis
3. Adductor longus
4. Adductor brevis
5. Adductor magnus

Adduction

-Femoral nerve (L2-L4)
-Accessory obtruator nerve (L2,3,4)

Adduction, flexion of the knee and medial rotation of hip

Anterior branch of obtruator

Flexion of the knee and medial rotation of hip

Adduction, assists in lateral rotation and flexion

Anterior branch of obturator

Adduction; assists in lateral
rotation and flexion

Posterior division of obturator (adductor part)
Tibial nerve (extensor part)

Adduction and extension of the thigh

Watch video

L1 – L4

S1 – S4

L4 – L5

Lumbosacral trunk (L4-L5) + Sacral plexus (S1-S4) =
LUMBOSACRAL PLEXUS

The lumbosacral plexus is formed by the ventral rami of L2-S3

Nerves that contain fibers from the superior rami of the plexus (L2 through L4)
innervate muscles in the anterior and medial thigh region that act on the hip and
knee joints

Nerves that contain fibers from the inferior rami of the plexus (S1 through S3)
innervate muscles of the leg that act on the ankle and foot joints.

The tibial and common fibular nerves travel through the gluteal region and thigh in a common connective
tissue sheath and together are called the SCIATIC NERVE.

The common fibular nerve divides in the proximal leg into superficial and deep fibular nerves.

L4

L5

S1

Obturator l2-l4

Femoral L2-L4

Common peroneal or fibular (L4-S2)

Tibial (L4-S3)

Superior gluteal (L4-S1)

Inferior gluteal (L5-S2)

Sciatic nerve (L4-S3)
Condition is siatica

1. Hamstring group
2. Adductor magnus

The hamstring and quadriceps
muscle groups are particularly
at risk for muscle strains
because they cross both the hip
and knee joints

Compartment syndrome is a devastating condition where an
osseofascial compartment pressure
rises to a level that decreases
perfusion. Causes are things like trauma, burns, tight cast, crush injury.