L6 Gluteal Region, Psoterior Thigh, And Leg

Question 1

LE has

Answer 1

Hip joint btw thigh and pelvis
Os coxa
Sacrum
Coccyx

Knee joint btw femur and tibia and fibula
Tibia = larger and medial
Fibula = strut bone

Ankle connects foot and leg
Tarsals, metatarsals, phalanges

Question 2

Bipedal stance is allowed because

Answer 2

The axes of rotation of the pelvis and hip are anterior to the transverse plane and the axes of rotation of knee and ankle are posterior to transverse plane in lateral view

They balance each other out and it keeps us stable

Erector spinae and iliopsoas have a role in this

Question 3

Gait cycle

Answer 3

One cycle of swing and stance by one limb

Pick a LE to follow

Starts w/ heel strike (initial contact) foot dorsiflexed

Foot becomes flat , forward propulsion is moving through out

Movement moves through medial side of foot through big toe

(^stance phase)

Toe off/push off (preswing) foot plantarflexed

Swing foot through air in forward motion so you can’t touch down on heel strike again (swing phase)

Question 4

Limb rotation does what in development

Answer 4

As limbs develop- they come out laterally and then come forward (clapping hands and feet)

UE move laterally

LE move medially

Moves anterior compartment of embryonic lower limb to posterior side of body
(Still flexing, but posterior now!)

Question 5

Lumbosacral plexus

Answer 5

Contributions from L2-S3

Anterior (embryonically) division nerves are in posterior compartment

Posterior (embryonically) division nerves are in anterior compartment

Made up of ANTERIOR RAMI (SE, SA mainly)

Posterior compartment nerves:
superior and inferior gluteal n.
Nerve to piriformis
^ those two called sacral plexus (gluteal region)

Sciatic nerve (huge, not a real nerve, branches in 2
Common fibular n.
Tibial n. (Posterior thigh and leg)

Question 6

Hip joint

Answer 6

Btw femur and acetabulum of os coxa bone

All axes of rotation (stability over wide range of movement

Ligaments:
Iliofemoral
Pubofemoral

Movements: 
  Flex
  Extend 
  Abduction
  Adduction 
  Medial rotation 
  Lateral rotation 
  (All sane is shoulder)

Question 7

Gluteal muscles mainly act on the

Answer 7

Hip

Gluteus Maximus
Gluteus medius and minimus (work together)

Question 8

Gluteus Maximus

Answer 8

Posterior to hip joint

A: lateral rotation, hip extension

N: inferior gluteal n

Extending powerfully from flexion

Question 9

Gluteus medius and minimus

Answer 9

Cross anterior/posterior axis and transverse axis

A: hip abduction, anterior fibers medial rotation

N: superior gluteal n. (Also innervates tensor fasciae latae which is more anterior hip abduction/medial rotation/ flexion)

Steadies pelvis on one leg when opposite leg is raised

Question 10

Piriformis

Answer 10

Landmark that divides between structure ms that emerge from superior gluteal region and inferior gluteal region

Nothing goes through it typically

Anything superior = superior gluteal n

Anything inferior= inferior gluteal n

Sciatic passes inferior to piriformis but doesn’t innervate anything in gluteal region

Question 11

Innervation to gluteal region

Answer 11

Scaral plexus

Inferior and superior gluteal n

Small lateral rotators innervated by branches of sacral plexus

Motor- from posterior division nerves to gluteal region

Sensory- from superficial gluteal nerves

Question 12

Trendelenberg test

Answer 12

Person asked to stand on one leg

Gluteus medius and minimus typically contract as soon as contralateral foot leaves floor preventing pelvis from tipping to unsupported side

Positive sign= lesion to superior gluteal nerve on opposite side where sagging occurs

Question 13

Piriformis syndrome

Answer 13

Sciatic n really composed of two nerves (tibial and common fibular) wrapped in same epineurium

Doesn’t have typical emergence

Common fibular can pierce through piriformis or emerge superior to piriformis

If pierces, can be impinged and you’ll see loss of function downstream

Question 14

Gluteal region in locomotion

Answer 14

Hip extensors (gluteus Maximus) help with deceleration (reverse forward swing) during heel strike

Hip abductors of contralateral side stabilize pelvis to prepare for swing phase

Question 15

Compartments of thigh

Answer 15

Anterior
Posterior
Medial

Deep fascia - sleeve around all muscles
Thickening of fascia on lateral side =iliotibal tract “IT band”

Tibial n.

Main actions: flexors of knee, extend hip(if cross that joint)

Question 16

Knee

Answer 16

Patella - large sesamoid bone (develops in tendon)

Tensor fasciae latae inserts on IT band

Medial(tibial) collateral ligament woven in with
Medial meniscus (injury to 1= injury to both)
Medial condyle

Lateral(fibular) collateral ligament
Lateral meniscus
Lateral condyle

Cruciate ligaments - anterior and posterior cross each other (btw condyles)

Question 17

Knee articulation btw femur and tibia

Answer 17

Fibula doesn’t participate

Hinge shaped synovial - only transverse axis

Only flexion and extension

Femur condyles are incongruent w tibia some rotation occurs when knee is flexed

Question 18

Posterior thigh muscles

Answer 18

Hamstrings: semitendinosus, semimembranosus, biceps femoris (long head)
Common origin from ischial tuberosity
A: extend hip , flex knee
N: tibial division of sciatic n.

Biceps femoris (short head) not hamstring lower origin
A: flex knee
N: common fibular division of sciatic n.

Question 19

Tibial division of sciatic n

Answer 19

Emerges inferior to piriformis

Passes deep to long head of biceps femoris

Motor innervation to hamstrings (except short head)

Passes through popliteal fossa (knee pit) to posterior leg separates in inferior 1/3 of thigh into common fibular (laterally) and tibial n

Sensory info for posterior thigh travels through sacral plexus NOT sciatic n

Question 20

Posterior thigh in locomotion

Answer 20

Knee flexors work in balance with quadriceps to decelerate extension of the knee during swing phase

Also helps clear the foot during swing phase so toes don’t drag on the ground

Question 21

posterior compartment of the leg

Answer 21

Superficial and deep groups

Tibia(medial) fibula (lateral)

Tibial n.

Main action: plantarflexion of foot, flexion of toes, inversion

Question 22

Foot joints

Answer 22

Ankle joint 
Transverse tarsal joint 
Tarsometatarsal (TMT) joint 
Metatarsophalangeal (MTP) joint 
Proximal interphalangeal (PIP) joints 
Distal interphalangeal (DIP) joints 

Lateral malleolus (bones projection fibula) 
Medial malleolus ( bones projection tibia) 
  Tibia and fibula participate in ankle

Tarsals
Metatarsals
Phalanges

Question 23

Ankle joint

Answer 23

Hinge shaped synovial

Only transverse axis

Dorsi flexion and plantarflexion

When plantarflexed some wobble adduction, abduction, inversion, and eversion in unstable position

Heel bone = calcaneous

Question 24

Intertarsal joints

Answer 24

Subtalar joint - where talus rests on calcaneus
Plane shaped synovial
Anteroposterior axis
Inversion and eversion

Transverse tarsal joint 
  Calcaneocuboid anteriorly 
  Talonavicular posteriorly 
  Plane shaped synovial 
  Anteroposterior axis
  Inversion and eversion

Question 25

Superficial posterior leg

Answer 25

Triceps Surae

Gastrocnemius two headed calf
A: plantarflex foot / flexes knee a little

Deep to that soleus
Tiny plantaris

All three insert on calcaneous and calcaneal/Achilles’ tendon

N: Tibial n.

A: plantarflex foot

Question 26

Deep posterior leg muscles

Answer 26

Popliteus
Unlocks knee when in extended position too long

Tibialis posterior
A: plantarflex and inverts foots

Flexor digitorium longus
A: flexes lateral toes

Flexor hallucis longus
A: flex big toe/hallux

All tibial n

Also a lot function in supporting the foot