Chapter 9: Leg Day of Hip & Lower Limb

The limb is made of how many body segments?

6

How do the 6 spinal nerves innervate?

3 superior and 3 inferior

What nerve innervates the anterior quadrant of the hip-thigh?

Femoral L2-L4

What nerve innervates the medial quadrant of the hip-thigh?

Obturator L2-L4

What nerve innervates the lateral quadrant of the hip-thigh?

Fibular + Gluteal L5-S2

What nerve innervates the posterior quadrant of the hip-thigh?

Tibial L5-S2

The Os Coxae is a fusion of what 3 bones?

Ilium, ischium, pubis

Anterior quadrant muscles attach to ______ & are innervated by_______?

Front ilium

Femoral nerve

Medial quadrant muscles attach to ______ & are innervated by_______?

Pubis

Obturator nerve

Lateral quadrant muscles attach to ______ & are innervated by_______?

Back of ilium

Fibular & gluteal

Posterior quadrant muscles attach to ______ & are innervated by_______?

Ischium

Tibial nerve

Why do lower limb muscles spiral?

1: Limbs start as little paddles

2: There's a knee and ankle, then

3: The foot turns forward, causing muscles to spiral across the front of the limb

Hip-Thigh: Anterior Muscles

1: Iliacus

2: Psoas Major

3: Sartorius (pes anserinus)

4: Rectus femoris

5: Vastus muscles (medialis, lateralis, intermedius)

6: 1/2 Tensor Fascia Latae

Hip-Thigh: Anterior Attachments

Anterior ilium + Femur + Patella

Hip-Thigh: Anterior Action

Flex the hip; Extend the knee

Hip-Thigh: Anterior Nerve

Femoral L2-L4

Hip-Thigh: Lateral Muscles

1: 1/2 Tensor Fascia Latae

2: Gluteus muscles (maximus, medius, minimus)

3: Piriformis

Hip-Thigh: Lateral Attachments

Posterior ilium (gluteal surface) + Femur (greater trochanter)

Hip-Thigh: Lateral Action

Abduction of the hip

Hip-Thigh: Lateral Nerve

Fibular & gluteal (superior + inferior) L5-S2

Hip-Thigh: Medial Muscles

1: Pectineus

2: Gracilis

3: Adductor muscles (Brevis, Longus, Magnus)

Hip-Thigh: Medial Attachments

Pubis + Femur (Linea Aspera)

Hip-Thigh: Medial Action

Adduction + medial rotation of the hip

Hip-Thigh: Medial Nerve

Obturator L2-L4

Hip-Thigh: Posterior Muscles

1: Biceps femoris (short and long head)

2: Semitendinosus

3: Semimembranosus

Hip-Thigh: Posterior Attachments

Ischium (ischial tuberosity) + Femur or Tibia & Fibula

Hip-Thigh: Posterior Actions

Extend the hip; Flex the knee

Hip-Thigh: Posterior Nerve

Tibial L5-S2 (except Biceps Femoris Short Head is innervated by Fibular Nerve L5-S2)

What is the femoral triangle?

A triangle shaped region that separates the anterior from the medial quadrants

What are the 3 parts to the femoral triangle?

Inguinal Ligament (superiorly)

Sartorius Muscle (laterally)

Adductor Longus (medially)

Where are each 3 parts of the femoral triangle located?

Inguinal Ligament: Superior from Anterior Superior Iliac Spine to pubic tubercle

Sartorius Muscle: Lateral edge

Adductor Longus: Medial Edge

What does the femoral triangle include in it?

Nerves

Artery

Vein

Lymphatics

(in that order)

What is the largest muscle group of the body in terms of mass?

Gluteal muscle group

Put the gluteal glutes from superficial to deep

Maximus, Medias, Minimus

Where is the piriformis located?

Deep under the gluteus maximus

Gluteal muscles can extend the hip, but only if what?

The hip is hyperflexed first

What is included in the suprapiraform portion?

Superior gluteal a., v., n

What is included in the infrapiraform portion?

Sciatic n.

Inferior gluteal a., v., n.

Internal pudendal a., v.

Pudendal n

What is included in the Lesser Sciatic Foramen?

Internal pudendal a., v.

Pudendal n

What is Pes Anserinus?

A place where 3 quadrants come together. It's an important stabilizer of the medial aspect of the knee joint.

What 3 quadrants are included in Pes Anserinus?

Sartorius, Gracilis, Semitendinosus

What is the position of all 3 quadrants of Pes Anserinus?

Sartorius - Superficial to gracilis

Gracilis - Distal to medial condyle of tibia

Semitendinosus - Distal to gracilis

Knee-to-Ankle: Anterior Muscle

1/2 Tibialis Anterior

Knee-to-Ankle: Anterior Attachments

Tibia + Tarsals/Metatarsals

Knee-to-Ankle: Anterior Actions

Dorsiflexion + Inversion of foot

What nerve innervates the anterior quadrant of the knee-to-ankle?

Fibular L4-L5 (innervated by the Femoral nerve as well because L4)

Knee-to-Ankle: Lateral Muscles

1/2 Tibialis Anterior

Extensor Digitorum Longus

Extensor Hallucis Longus

Fibularis Longus

Fibularis Brevis

Knee-to-Ankle: Lateral Attachments

Fibula + Phalanges/Metatarsals

Knee-to-Ankle: Lateral Action

Extension of digits + Eversion of foot + Plantar flexion

What nerve innervates the lateral quadrant of the knee-to-ankle?

Fibular L2-S5

Knee-to-Ankle: Medial Muscles

1/2 Tibialis Posterior

Knee-to-Ankle: Medial Attachment

Tibia + Tarsals/metatarsals

Knee-to-Ankle: Medial Action

Plantar flexion + inversion of foot

What nerve innervates the medial quadrant of the knee-to-ankle?

Tibial L4-L5 (innervated by the Obturator nerve as well because L4)

Knee-to-Ankle: Posterior Muscles

1/2 Tibialis Posterior

Gastrocnemius

Soleus

Plantaris

Popliteus

Knee-to-Ankle: Posterior Attachment

Femur + Calcaneous via the calcaneal tendon/phalanges

Knee-to-Ankle: Posterior Actions

Plantar flexion + Knee Flexion

What nerve innervates the posterior quadrant of the knee-to-ankle?

Tibial L5-S2

Describe the piriformis muscle & location

Triangle shaped; Under gluteus maximum

What is the location of all 3 gluteal muscles?

Medius: Along the top superior ridge

Maximus: Along the back

Minimus: Deep underneath the medius

The sciatic nerve passes under what muscle?

Gluteus maximus

Why is the gluteus medius muscle important clinically?

Best site for injection because of the large muscle mass. This site is located away from the gluteal arteries as well as the sciatic and gluteal nerves.

What two nerves combine to form the sciatic nerve?

Tibial nerve & fibular nerve

When stuck in heavy traffic you may experience a cramp in the anterior portion of the leg. Why?

There is only a single muscle that performs dorsiflexion but many that do plantar flexion