MSK Lower Limb Flashcards
Which muscles are found in the anterior compartment of the thigh?
Iliopsoas
Quadriceps
Sartorius
Pectineus
Which two muscles make up the ialipsoa?
Iliacus
Psoas major
Which four muscles make up the quadriceps?
Vastus lateralis
Vastus intermedius
Vastus medialis
Rectus femoris
What is the innervation for all the muscles in the anterior compartment of the thigh?
Femoral nerve
What are the nerve roots of the femoral nerve?
L2-4
Actions of iliopsoas?
Flexion of thigh at hip joint
->unlike other anterior thigh muscles, the iliopsoas does not perform extension at the knee joint
I know I just said the anterior thigh muscles are innervated by the femoral nerve and majority are!
But what is the psoas major innervated by?
Anterior rami of L1-3
The quadricep muscles mostly have the same action.
What is the collective action of the vastus lateralis. intermedius and medialis and the rectus femoris?
Extension of knee joint
Secondary function of stabilising patella
What is the additional action of the rectus femoris?
Flexion of hip joint
->only quad muscle which crosses both hip and knee
Longest muscle in the body?
Sartorius
Actions of sartorius?
Flexor at hip and knee
Also abductor and lateral rotator at hip
Actions of pectineus?
Adduction and flexion at hip joint
The muscles of the medial compartment of the thigh are also known as what?
The adductors
Which muscles are found in the medial compartment of the thigh?
Gracilis
Obturator externus
Adductor brevis
Adductor longus
Adductor magnus
What is the nerve supply to the adductor muscles in the medial compartment of the thigh?
Obturator nerve
Which muscle is the largest in the medial compartment of the thigh?
Adductor magnus
->comes from, the name
There are two parts to the adductor magnus muscle. What are the two components?
Adductor component
Hamstring component
There is different innervations for the adductor and hamstring component of the adductor magnus muscle.
What is the innervation for the adductor component?
Obturator nerve
->this make sense as the adductors are supplied by the obturator so makes sense for the adductor component to be too
There is different innervations for the adductor and hamstring component of the adductor magnus muscle.
What is the innervation for the hamstring component?
Tibial component of sciatic nerve
->again, matches the innervation of hamstrings
Action of adductor component of adductor magnus in the medial compartment of the thigh?
Adduction and flexion of thigh
Action of hamstring component of adductor magnus in the medial compartment of the thigh?
Adduction and extension of hip
->again makes sense as hamstrings are posterior and have a role in extension
Function of adductor longus?
Adduction of thigh
Function of adductor brevis?
Adduction of thigh
->well isn’t that a surprise
Action of obturator externus?
Adduction and lateral rotation of thigh
Action of gracilis?
Adduction of thigh
Flexion of leg at knee
And just to make sure it’s sunk in- what is the innervation of the adductor compartment muscles?
Obturator muscle
Muscles in the posterior compartment of the thigh?
Biceps femoris
Semitendonous
Semimembranous
aka hamstrings
The biceps femoris has two heads. Which is considered a part of the hamstrings?
Long head
Action of biceps femoris?
Flexion at knee
Extension at hip
Lateral rotation at hip and knee
Action of semitendonous muscle?
Flexion of leg at knee
Extension of thigh at hip
Medial rotation at hip and knee
Action of semimembranous?
Flexion of leg at knee
Extension of thigh at hip
Medial rotation at hip and knee
->so both of the semi muscles have a role is medial rotation at hip and knee (maybe think m=m)
Okay, so the innervation of the posterior compartment of the thigh differs a bit.
What is the innervation of the long head of the hamstrings aka long head of biceps femoris, semitendonous and semimembranous?
Tibial part of the sciatic nerve
What is the innervation of the short head of the biceps femoris?
Common fibular part of sciatic nerve
Which of the hamstrings sits deeper than the others?
Semimembranous sits under semitendonous
Name the muscles in the anterior compartment of the leg.
Tibialis anterior
Extensor digitorum longus
Extensor hallucis longus
Fibularis tertius
->wee bit more confusing cos usually the extensors are in the posterior compartment but switches for the leg ig
Innervation of all the muscles in the anterior compartment of the leg?
Deep fibular nerve
Action of tibialis anterior, one of the anterior leg muscles?
Dorsiflexion and inversion of foot
Action of extensor digitorum longus, one of the anterior leg muscles?
Extension of lateral four toes
Dorsiflexion of foot
Action of extensor hallucis longus, one of the anterior leg muscles?
Extension of great toe
Dorsiflexion of foot
->basically, common action for anterior compartment is dorsiflexion of foot and each muscle has another function
Action of fibular tertius, one of the anterior leg muscles?
Eversion of foot
Dorsiflexion of foot
Nerve roots of deep fibular nerve?
L4-S2
Name the two muscles in the lateral compartment of the leg.
Fibularis longus
Fibularis brevis
What are the two muscles in the lateral compartment of the leg innervated by?
Superficial fibular nerve
What is another name for the fibular nerve?
Peroneal nerve
Action of fibularis longus?
Eversion of foot
Plantarflexion of foot
Action of fibularis brevis?
Eversion of foot
There are two layers of muscles in the posterior compartment of the leg- superficial and deep.
Name the three superficial posterior leg muscles.
Gastrocnemius
Soleus
Plantaris
What is the innervation for all the muscles in the posterior compartment of the leg- superficial and deep?
Tibial nerve
What is the action of the gastrocnemius, one of the superficial posterior compartment muscles in the leg?
Plantarflexion at ankle
Flexion at knee
What is the action of the soleus, one of the superficial posterior compartment muscles in the leg?
Plantarflexion of the foot at the ankle
What is the action of the plantaris, one of the superficial posterior compartment muscles in the leg?
Plantarflexion at ankle
Flexion at knee
Which muscle sits superficial to the soleus?
Gastrocnemius
Name the four muscles in the deep layer of the posterior compartment of the leg.
Popliteus
Flexor digitorum longus
Flexor hallicus longus
Tibialis posterior
As mentioned before, what will be the innervation for these deep muscles of the posterior compartment of the leg?
Tibial nerve
Action of popliteus?
Unlocks knee joint basically to flexion can occur by laterally rotating femur
Action of the flexor digitorum longus?
Flexion of lateral four toes
Action of flexor hallicus longus?
Flexion of great toe
Action of tibialis posterior?
Inversion and plantarflexion of foot
Muscles of the foot, like the hand, can be divided into intrinsic and extrinsic muscles.
We have already discussed the extrinsic muscles as they arise from the anterior, lateral and posterior compartments of the leg.
What are the two intrinsic muscles located within the dorsum of the foot?
Extensor digitorum brevis
Extensor hallucis brevis
What is the innervation for the extensor digitorum brevis and extensor hallucis brevis?
Deep fibular nerve
->remember, can also be known as the peroneal nerve
Action of the extensor digitorum brevis in the dorsum of the foot?
Extension of lateral four toes
Action of the extensor hallucis brevis in the dorsum of the foot?
Extension of great toe
Okay, in the plantar aspect of the foot, there are ten muscles divided into four layers from superficial to deep.
Name the three muscles in the first layer (most superficial).
Abductor hallucis
Flexor digitorim brevis
Abductor digit minimi
Innervation of abductor hallucis?
Medial plantar nerve
Action of abductor hallucis?
Abduction and flexion of great toe
Innervation of flexor digitorum brevis?
Flexion of lateral four toes at PIP joints
Innervation of abductor digit minimi?
Lateral plantar nerve
Action of abductor digiti minimi?
Abduction and flexion of little toe
Name the two muscles in the second layer of the plantar aspect of the foot.
Quadratus plantae
Lumbricals
Innervation of quadratus plantae?
Lateral plantar nerve
Action of quadratus plantae?
Assists in flexion of lateral four toes
->assists flexor digitorum longus
Innervation of lumbricals of foot?
Medial lumbrical = medial plantar nerve
Lateral lumbricals= lateral plantar nerve
Action of the lumbricals of the foot?
Flexion at MTP joints
Extension at IP joints
Name the three muscles in the third layer of the foot
Flexor hallicus brevis
Adductor hallucis
Flexor digiti minimi brevis
->btw with the muscles of the foot, they are pretty dificult to identify on the specimens we have so idk how much they will ask
Innervation of adductor hallucis of the foot?
Deep branch of lateral plantar nerve
Innervation of flexor hallucis brevis of foot?
Medial plantar nerve
Innervation of flexor digiti minimi brevis of foot?
Superficial branch of lateral plantar nerve
Action of flexor hallucis brevis of foot?
Flexion of great toe at MTP joint
Action of adductor hallucis of foot?
Adduction of great toe
Action of the flexor digiti minimi brevis of the foot?
Flexion of little toe at MTP joint
Name the two muscles in the fourth layer of the plantar foot (deep layer).
Dorsal and plantar interossei
Innervation of the plantar interossei of the foot?
Lateral plantar nerve
Innervation of the dorsal interossei of the foot?
Lateral plantar nerve
Action of the plantar interossei of the foot?
Adduction of lateral three digits (PAD)
Flexion at MTP joints
Action of the dorsal interossei of the foot?
Abduction (DAB) of lateral four digits
Flexion at MTP joints