Lower Limb Anatomy

4 characteristics of synovial joints

Articular cartilage, synovial membrane, joint cavity, joint capsule

Lumbosacral joint

B/w L5 and S1, cartilaginous, stabilized by iliolumbar ligaments

Sacroiliac joints

B/w lateral sacrum and medial iliac bones, synovial, nonaxial, stabilized by sacroiliac ligaments

What do sacroiliac ligaments do

Limit inferior dislocation of sacrum

What do sacrotuberous and sacrospinous ligaments do

Limit anterior dislocation of sacrum and transfer weight to LL

Hip joint

B/w head of femur and acetabulum, synovial

What is the acetabular labrum

Rim of cartilage, increases hip join stability

What is the anterior ligament on the hip and what does it do

iliofemoral ligament (Y), limits hip extension

What is the posterior ligament on the hip and what does it do

ischiofemoral ligament, increases stability

Pubic Symphysis

B/w L and R pubic bones, cartilaginous

Superficial fascia

Loose CT, holds fat & water, protective layer, path for superficial vessels and nn

Deep fascia

Dense CT, no fat or water, surrounds and compartmentalizes mm groups, mm attachment

What is deep fascia called in the thigh

Fascia lata

What is deep fascia called in the leg

Crural fascia

What is the action of a muscle

What happens when m contracts

Gluteus maximus m attachments

Posterior superior ilium, sacrum, sacrotuberous ligament to iliotibial tract, gluteal tuberosity on femur

Gluteus maximus innervation

Inferior gluteal nerve

Gluteus maximus action

power hip extension, lateral rotation, abduction

Gluteus maximus function

Walking- limits hip flexion, running and climbing stairs- hip extension

Tensor fascia latae m attachments

Iliac crest to iliotibial tract

Tensor fascia latae innervation

Superior gluteal nerve

Tensor fascia latae action

Hip flexion, medial rotation , abduction

Tensor fascia latae function

Standing/running/walking- laterally stabilize hip and knee

Gluteus medius and minimus mm attachments

Gluteal surface of ilium to greater trochanter of femur

Gluteus medius and minimus innervation

Superior gluteal nerve

Gluteus medius and minimus action

abduction and medial rotation

Gluteus medius and minimus function

Walking/running- limits hip adduction

Hip intrinsic mm attachment

Posterior ischium to posterior femur

Hip intrinsic mm innervation

Individual spinal nn

Hip intrinsic mm action

Hip lateral rotation adn abduction

Hip intrinsic mm function

Proprioception

List hip intrinsic mm from superior to inferior

Piriformis, superior gemellus, obturator internus, inferior gemellus, quadratus femoris

Differences and similarities between cranial and spinal nn

Both have somatic and autonomic function, cranial has special sense function

What is a reflex arc

Stereotypical motor event driven by a sensory stimulus

What are the 5 points of a typical reflex arc

Receptor, sensory neuron, interneuron, motor neuron, target organ

What are interneurons

Communicate b/w L and R sides, and can travel up the spinal cord

How many pairs of spinal nn are there

31 bilateral pair

What is the somatic function of spinal nn

Body walls and limbs

What is the autonomic function of spinal nn

Sympathetic

Where do the spinal nn emerge from

Intervertebral foramina

What is the relationship between spinal nn and bony vertebrae

Same number in each segment except cervical, one more n than vertebrae

What is a nerve plexus

Network/joining of spinal nerves

What makes up the lumbosacral plexus

Anterior rami of spinal nerves L1-S4

What nn make up the lumbosacral plexus

Femoral, obturator, superior gluteal, inferior gluteal, sciatic

What does femoral n innervate

Anterior thigh mm

What does obturator n innervate

Medial thigh mm

What does superior gluteal n innervate

Gluteus medius, minimus, and tensor fascia latae

What does inferior gluteal n innervate

Gluteus maximus

Paresis

weakness in voluntary movement

Paralysis

Complete loss of voluntary movement

What does sciatic n innervate

posterior thigh mm

What 2 portions does the sciatic nerve split into

Tibial and common fibular

What does the tibial n innervate

Posterior leg mm

What 2 portions does the common fibular n split into

Superficial fibular n and deep fibular n

What does superficial fibular n innervate

lateral leg mm

What does deep fibular n innervate

Anterior leg mm

Anastomosis

Joining of any 2 vessels with different origins

Collateral circulation

Collateral vessels and their anastomoses

What is a key feature of venous supply

One way valves

Features of deep vv

Same name as a they run with, venae comitantes

Features of superficial vv

Own name

Great saphenous v path

Dorsal venous arch to medial leg and thigh to femoral vein

Lesser saphenous v path

Dorsal venous arch to posterior leg to popliteal v

What are bursae

Synovial sacs that reduce friction

Describe patella

Sesamoid bone, develops in quadriceps tendon, connects to tibia via patellar ligament

Functions of patella

Decrease friction, increase leverage, protect the knee joint anteriorly, keeps tendons from fraying, femoral obliquity

Describe menisci

Cartilage, low blood supply, thicker on outer edges

Functions of menisci

Shock absorber, decrease friction, allows for movement, increases stability of joint

Medial meniscus features

Incomplete ring, firmly attached to tibia, anchored ot medial collateral ligament

Lateral meniscus features

weakly attached to tibia, more complete ring

Function of collateral ligament

Limit rotation of femur on tibia

Function of lateral collateral ligament

Limit adduction of tibia

Function of medial collateral ligament

Limit abduction of tibia

Function of anterior cruciate ligament

Limits anterior movement of tibia

Function of posterior cruciate ligament

Limits posterior movement of tibia

Functions of cruciate ligaments

Limit knee rotation and hyperextension

Thigh muscles overall function

Propulsion

Anterior thigh innervation

Femoral n

Iliopsoas m distal attachment

Lesser trochanter

Psoas m proximal attachment

T12-L5 vertebrae

Iliacus m proximal attacahment

Iliac fossa

Iliopsoas m action

Primary hip flexor

Quadriceps femoris mm action

Collectively flex hip and extend knee

Quadriceps femoris mm distal attachment

Tibial tuberosity

Rectus femoris m proximal attachment

Anterior inferior iliac spine

Vastus mm proximal attachment

Femur

Sartorius m attachments

Anterior superior iliac spine to medial proximal tibia

Sartorius m action

Hip flexion, knee flexion, hip abduction, hip lateral rotation

Posterior thigh mm action

Hip extension, knee flexion

Posterior thigh mm innervation

Sciatic n

Posterior thigh mm proximal attachment

Ischial tuberosity

Biceps femoris m distal attachment

Head of fibula

Biceps femoris short head proximal attachment

Posterior femur

Semitendinosus m distal attachment

Medial proximal tibia

Semimembranosus m distal attachment

medial condyle of tibia

Medial thigh mm action

Hip adduction

Medial thigh mm innervation

Obturador n (mostly)

Medial thigh mm attachments

Pubis to femur

What does injury to obturator n cause

Instability in pelvis because it can’t resist abduction

Pectineus m attachments

Superior pubic ramus to pectineal line