L6 Gluteal Region, Psoterior Thigh, And Leg Flashcards
LE has
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
Bipedal stance is allowed because
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
Gait cycle
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)
Limb rotation does what in development
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!)
Lumbosacral plexus
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)
Hip joint
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)
Gluteal muscles mainly act on the
Hip
Gluteus Maximus
Gluteus medius and minimus (work together)
Gluteus Maximus
Posterior to hip joint
A: lateral rotation, hip extension
N: inferior gluteal n
Extending powerfully from flexion
Gluteus medius and minimus
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
Piriformis
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
Innervation to gluteal region
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
Trendelenberg test
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
Piriformis syndrome
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
Gluteal region in locomotion
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
Compartments of thigh
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)
Knee
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)
Knee articulation btw femur and tibia
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
Posterior thigh muscles
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.
Tibial division of sciatic n
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
Posterior thigh in locomotion
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
posterior compartment of the leg
Superficial and deep groups
Tibia(medial) fibula (lateral)
Tibial n.
Main action: plantarflexion of foot, flexion of toes, inversion
Foot joints
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
Ankle joint
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
Intertarsal joints
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
Superficial posterior leg
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
Deep posterior leg muscles
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
