MSK-anatomy-HARC Flashcards
which cranial nerve supplies the muscles of facial expression?
-cranial nerve VII—>the facial nerve
what are the muscles of facial expression responsible for?
- moving the skin to provide facial expression
- act as sphincters around the eyes and mouth
what are the muscles of mastication responsible for?
moving the mandible at the Temporomandibular joint
which cranial nerve supplies the muscles of mastication?
cranial nerve V – the trigeminal nerve
where are the muscles of mastication derived from?
pharyngeal arch I
what are the different branches of the trigeminal nerve and what types of nerves are they?
- Ophthalmic (V1)- sensory
- Maxillary (V2)- sensory
- Mandibular (V3)- sensory & motor to muscles of mastication
name the branches of the facial nerve?
Temporal Zygomatic Buccal Marginal mandibular Cervical
how many cervical vertebrae are there?
7
how many cervical spinal nerves are there?
8
how many thoracic vertebrae and spinal nerves are there?
12
how many lumbar vertebrae and spinal nerves are there?
5
how many sacral vertebrae and spinal nerves are there?
5
how many coccygeal vertebrae are there?
3/4
how many coccygeal spinal nerves?
1
what forms the coccyx?
3/4 coccygeal vertebrae are fused
what are the roles of intervertebral discs?
- act as shock absorbers by keeping vertebrae separated when there is impact
- provide flexibility to spine-facilitating flexion and extension
what is the the annulus fibrosis made up of?
- made of fibrocartilage
- tough and collagenous
what is the role of the annulus fibrosis?
prevents over-rotation of the vertebrae
what is the nucleus pulposus made up of?
jelly-like- mainly composed of water & loose network of collagen
what is the role of the nucleus pulposus?
allows discs to withstand forces of compression and torsion
which cervical vertebrae is atlas?
C1
what is different about atlas compared with other cervical vertebrae?
C1 is only cervical vertebra that has no spinous process
which cervical vertebrae is axis?
C2
does C2 have a spinous process?
yes-bifid spinous process
what is the joint between skull base and C1 called?
Atlanto-occipital joint
which movements occur at the Atlanto-occipital joint?
Flexion & extension occurs at this joint between the skull & C1 (e.g. when you nod & say yes)
what is the joint between c1 and c2 called?
Atlanto-axial joint
what does the articulation between c1 and c2 allow?
allows you to shake your head left & right (eg. when you shake your head & say no)
how is c1 arranged above c2?
C1 slotted over C2 (anterior arch of C1 slots over the dens process of C2)
what is the role of the ligamentum nuchae?
limits hyperflexion of neck, keeps your head from dropping
what is the role of suprapinous ligament?
strong, fibrous cord that helps maintain upright position of head and (limit hyperflexion of the whole vertebral column)
what is the role of the interspinous ligament?
limit flexion by restricting separation of spinous process
what is the role of the ligamentum flavum?
maintains upright posture, helps preserve normal curvature and straightens column after flexion (elasticity can reduce with old age)
what is the role of anterior longitudinal ligament?
limits extension
what is the role of posterior longitudinal ligament?
limits flexion
the temporalis muscle is innervated by which muscle? a-Facial nerve b-Ophthalmic nerve c-Mandibular nerve d-Maxillary nerve e-Superficial temporal nerve
c-mandibular nerve
which of these structures does not pass through the jugular foramen? a-CN IX b-Internal jugular vein c-CN XII d-CN X e-CN XI
c-CN XII
which bone of the forearm does the capitulum articulate with?
articulates with radius (round head)
which bone of the forearm does the trochlea articulate with?
articulates with ulna
what are the 4 rotator cuff muscles?
SITS
- supraspinatus
- infraspinatus
- teres minor
- subscapularis
what is the role of supraspinatus?
initiation of abduction
what is the role of the infraspinatus?
lateral rotation of humerus
what is the role of the teres minor?
lateral rotation of humerus
what is the role of the subscapularis?
medial rotation of humerus
where is the innervation of the upper limb derived from?
derived from brachial plexus
what is the order of the brachial plexus?
roots—>trunks—->divisions—->cords—–>terminal nerves
what are the different roots of the brachial plexus?
c5 c6 c7 c8 t1
what are the different terminal nerves of the brachial plexus?
- musculocutaneous
- median
- radial
- ulnar
where are the cords of the brachial plexus arranged?
around 2nd part of axillary artery
what is the median nerve formed by?
lateral and medial cords
what is the musculocutaneous nerve formed by?
lateral cord
what is the radial nerve formed by?
posterior cord
what is the ulnar cord formed by?
medial cord
which roots form musculocutaneous nerve?
c5/6/7
only nerve with no t1
which roots form median nerve?
c6/ c7/ c8/ t1
which roots form radial nerve?
c5/ c6/ c7/ c8/ t1
which roots form ulnar nerve?
c7/ c8/ t1
what are the muscles in the anterior compartment of the upper arm?
BBC
- biceps brachii
- brachialis
- coracobrachialis
which nerve innervates the anterior compartment of the upper arm?
musculocutaneous nerve
what is the role of the biceps brachii?
flexor & supinator of the forearm + weak flexor of humerus
what is the role of the brachialis?
flexor of forearm
what is the role of the coracobrachialis?
flexor and adductor of humerus
which muscles make up the posterior compartment of the upper arm?
medial, lateral & long heads of triceps brachii
which nerve innervates the posterior compartment of the forearm?
radial nerve
what is the role of triceps brachii?
extension of forearm
what are the 3 ligaments of the elbow joint?
- radial collateral ligament
- annular ligament
- ulna collateral ligament
what are the primary muscles of supination?
- Biceps brachii
- Supinator (posterior- deep layer)
what are the primary muscles of pronation?
- Pronator quadratus (anterior- deep layer)
- Pronator teres (anterior- superficial layer)
are muscles in the anterior compartment of forearm extensors or flexors?
flexors
which nerve innervates the anterior compartment of the forearm?
median nerve
EXCEPT for flexor carpi ulnaris & medial half of flexor digitorum profundus (innervated by ulnar nerve
what are the 3 deep muscles of the anterior compartment of the forearm?
- Pronator quadratus
- Flexor digitorum profundus
- Flexor pollicis longus
what is the middle muscle of the anterior compartment of the forearm?
Flexor digitorum superficialis
what are the 4 superficial muscles of the forearm?
- Pronator teres
- Palmaris longus
- Flexor carpi ulnaris
- Flexor carpi radialis
are the muscles of the posterior compartment of the forearm extensors or flexors?
extensors
which nerve innervates the posterior compartment of the forearm?
radial
what are the 5 deep muscles of the posterior compartment of the forearm?
- Supinator
- Extensor pollicis brevis
- Extensor pollicis longus
- Extensor indicis
- Abductor pollicis longus
what are the 7 superficial muscles of the posterior compartment of the forearm?
- Brachioradialis
- Extensor carpi radialis longus
- Extensor carpi radialis brevis
- Extensor carpi ulnaris
- Extensor digitorum
- Extensor digiti minimi
- Anconeus
what is the role of the flexor digitorum profundus?
- > inserts on distal phalanges
- > flexes distal interphalangeal joints
what is the role of the Flexor digitorum superficialis?
- > inserts on middle phalanges
- > flexes proximal interphalangeal joints
what is the common origin of anterior superficial muscles of forearm: Pronator teres,
Palmaris longus,
Flexor carpi ulnaris,
Flexor carpi radialis?
medial epicondyle of humerus
what is the common origin of the posterior muscles of forearm: Extensor carpi radialis brevis Extensor carpi ulnaris Extensor digitorum Extensor digiti minimi Anconeus?
lateral epicondyle of humerus
where does posterior muscle of forearm- brachioradialis originate from?
originates from lateral supracondylar ridge of humerus
where does posterior muscle of forearm- extensor carpi radialis longus originate from?
supracondylar ridge of humerus
name the 8 carpal bones?
- scaphoid
- lumate
- triquetrum
- pisiform (is a sesamoid bone)
- hamate (has a hook)
- capitate (largest)
- trapezoid
- trapezium
what kind of joint is a wrist joint?
condyloid
which 4 bones are involved in the articulation of the wrist joint?
radius, scaphoid, lunate + triquetrum
how do carpal bones articulate with radius?
Carpal bones form a convex surface, which articulates with the concave surface of the radius and articular disc
what is carpal tunnel syndrome caused by?
caused by compression of median nerve
which vein of the upper limb is a common site of venepuncture?
median cubital vein
what is median cubital vein formed by?
cephalic & basilic veins
which nerve innervates the dorsum of the hand (posterior)?
mainly radial
which nerve innervates the palm of the hand (anterior) and tips of digits?
mainly median
which part of the hand does the ulnar nerve innervate?
Ulnar side (5th digit & medial half of 4th)
what does damage to radial nerve cause?
wrist drop
does the radial nerve innervate intrinsic muscles of hand?
no
which muscles in anterior compartment of forearm does the median nerve not innervate?
flexor carpi ulnaris & medial half of flexor digitorum profundus
what would happen is the median nerve was severed at the elbow?
can’t flex 2nd & 3rd digits (Benediction sign)
does the ulna nerve supply thenar muscles ?
no-median nerve does
when do ulna nerve injuries commonly occur?
when the medial epicondyle fractures
Which cord of the brachial plexus gives rise to the radial nerve? a-Lateral b-Posterior c-Medial d-Median e-Anterior
b-posterior
Which of these muscles causes medial rotation of the humerus? a-Biceps brachii b-Teres minor c-Supraspinatus d-Subscapularis e-Deltoid
d-subscapularis
Which of these muscles is NOT innervated by the radial nerve? a-Brachioradialis b-Abductor pollicis brevis c-Medial head of triceps brachii d-Extensor digitorum e-Supinator
b-Abductor pollicis brevis
what are the differences between male and female pelvis?
Larger sub-pubic angle in female pelvis (90-100) (70 in males) & wider pelvic inlet
-> adapted for childbirth
what type of joint is the hip joint?
Ball-and-socket joint
what is the socket of the hip joint?
acetabulum
what is the ball of the ball and socket joint?
head of femur
what is the blood supply to the femoral head?
the medial & lateral circumflex branches (of the profunda femoris)
what does the lumbosacral plexus give rise to?
femoral, sciatic and obturator nerves
what are the different classifications of hip muscles?
- extrinsic hip muscles
- intrinsic hip muscles
- hip adductors
- hip flexors/knee extensors
- hip extension/ knee flexion
name the extrinsic muscles of the hip and their function?
Iliacus + psoas major muscles
-> iliacus
-Allows hip flexion
name the superficial intrinsic muscle of the hip and its function?
Superficial = gluteus maximus
-> most powerful hip extensor
name the deep intrinsic muscles of the hip and their function?
Deep = gluteus medius & gluteus minimus
-> both abduct hip
what is excessive hip drop caused by?
Excessive hip drop is primarily a result of weakness in the gluteus medius
how many compartments of the thigh are there?
3
anterior, posterior & medial
which compartment of the thigh are the hip adductors?
medial
name the most powerful hip adductor?
Adductor magnus
which nerve innervates the hip adductors?
obturator nerve (L2 – L4)
what compartment of the lower limb are the hip flexors and knee extensors?
anterior
which 4 muscles make up the quadriceps?
- Rectus femoris
- Vastus lateralis
- Vastus medialis
- Vastus intermedius (located underneath rectus femoris)
which nerve innervates the quadriceps?
Innervated by femoral nerve (L2 – L4); motor to quadriceps & sartorius
what is the function of the sartorius and the rectus femoris?
hip flexion
knee extension
what is the function of the vastus medialis?
knee extension
which compartment of the lower limb are hip extensors and knee flexors?
posterior compartment
hamstrings
which 3 muscles make up the posterior compartment of lower limb (hamstrings)?
- Biceps femoris (long & short heads)
- Semi-tendinosis
- Semi-membranosis
which nerve innervates the posterior compartment of the thigh (hamstring)?
Innervated by sciatic nerve (L4 – S3); motor to hamstrings and ALL muscles of leg & foot
which nerves does the sciatic nerve split into?
-> sciatic nerve splits into common peroneal & tibial nerves in popliteal fossa
what is the function of biceps femoris?
- hip extension
- knee flexion
- lateral rotation
describe the function of semi-membranous muscle?
- hip extension
- knee flexion
- lateral rotation
what type of joint is the knee joint?
synovial hinge joint
which movements occur at the knee joint?
flexion/ extension but some rotation and translation
which 3 bones make up the knee joint?
femur, tibia and patella
what are the 2 articulations of the knee joint?
tibiofemoral joint & patellofemoral joint
what are some of the primary stabilising features of the knee joint?
liagments: ACL PCL MCL LCL
what are the secondary stabilising features of the knee joint?
muscles-hamstrings
what movement does the ACL (anterior cruciate ligament) resist?
-resists anterior tibial translation
OR
-resists posterior femoral translation
what movement does PCL (posterior cruciate ligament) resist?
-resists posterior tibial translation
OR
-resists anterior femoral translation
what movements do the lateral and medial collateral ligaments control?
control the side to side motion of your knee and brace it against unusual movement
what shape is the medial menisci and how does this affect mobility?
- C-shaped
- less mobile
- more risk of injury
what shape is the lateral menisci and how does this affect mobility?
- almost O-shaped
- more mobile
- less risk of injury
what are menisci made of?
rings of fibrocartilage
how many compartments is the lower leg split into?
3
- anterior
- posterior
- lateral
what is the role of the lateral compartment of the lower leg?
eversion of the foot
which nerve innervates the lateral compartment of the lower leg?
superficial fibular nerve
which two muscles are in the pair of foot evertors?
- fibularis longus (attached to 1st metatarsal)
- fibulairs brevis (attached to 5th metatarsal)
where do tendons pass into the foot?
behind the lateral malleolus
what movements are the muscles in the anterior component of the lower leg responsible for?
- dorsiflexion, inversion of ankle
- extension of toes
which nerve innervates the muscles in the anterior component of the lower leg?
deep fibular nerve
which muscles are in the anterior component of the lower leg?
- tibialis anterior
- fibularis tertius
- extensor hallucis longus
- extensor digitorum longus
what is the role of tibialis anterior?
- primary dorsiflexor
- primary invertor-as attached to medial surface of foot
what is the role of the fibularis tertius?
the third evertor
what is the role of extensor hallucis longus and extensor digitorum longus?
toe extensors
what movements are the muscles in the posterior component of the lower leg responsible for?
plantarflexion, inversion, flexion of toes
which nerve innervates the posterior component of the lower leg?
tibial nerve
which muscles are in the superficial layer of the posterior component of the lower leg?
- > triceps surae (gastrocnemius + soleus)
- >plantaris
which muscles are in the deep layer of the posterior component of the lower leg?
tibialis posterior, popliteus & toe flexors
where does the gastronemius attach?
to posterior femur
what is the roles of the muscles making up the triceps surae?
- powerful plantarflexors
- gastronemius=knee flexor
what is the role of the plantaris?
plantarflexor and knee flexor
where does the plantaris insert?
next to calcaneal tendon
what is the role of tibilais posterior?
plantar flexion and inversion of ankle
what is the role of flexor hallicus longus and flexor digitorum longus?
toe flexors
hallicus=big toe only
digitorum=toe 2-5
what is the role of the popliteus?
medial rotation of knee
name the tarsal bones
-talus
-calcaneus
-navicular
((-medial
-intermediate
-lateral (cuneiform))
-cuboid
Tiger Cubs Need MILC
where is the talocrural joint?
between talus and leg
where is the subtalar joint?
between talus and calcaneum
what kind of joint is the talocrural joint?
-Synovial hinge between talus and crus (bones of the leg)
what movements does the talocrural joint allow?
Uniaxial – one movement only, these movements are dorsi and plantar flexion
what does the irregular shape of the talus mean for dorsi and plantar flexion?
Irregular shape of talus means bones are more congruent in dorsiflexion than plantarflexion
- > more stable in dorsiflexion
- > more risk of injury in plantarflexion
which movements does the subtalar joint allow?
Allows eversion & inversion
Inversion – 35 degrees; equivalent to supination of hand
Eversion – 20 degrees; equivalent to pronation of hand
name the 2 types of ankle ligaments
medial
lateral
what are the features of medial ankle ligament?
- deltoid lig
- single
- strong
- thick ligament
- more stable
what are the features of lateral ankle ligaments?
- numerous
- thinner
- weaker
- more hyperinversion injuries
which muscle is the most powerful hip extensor? a-Gluteus medius b-Rectus femoris c-Biceps femoris d-Gluteus medius e-Gluteus maximus
e
Which of the following structures resists posterior tibial translation? a-Medial collateral ligament b-PCL c-Lateral collateral ligament d-ACL e-Sartorius
b