Interval 7: Axilla, Arm, Thigh Flashcards
Main (general) functions of the pectoral girdle
-connect upper limb to axial skeleton
5 muscles clavicle provides attachment for
Pectoralis major Deltoid Trapezius Sternocleidomastoid Subclavius
________ is the first bone in the body to ossify.
- Clavicle
- Has both intramembranous and endochondral modes of ossification
T/F: Clavicle is a long bone so it therefore has a medullary cavity
-False; it is a long bone but it lacks a medullary cavity
The clavicle is the most frequently broken bone in the body. In particular, which part of the bone is the weakest?
- Junction of its medial 2/3s and lateral 1/3
- also the point where medial and lateral curvatures meet
Why is “separation of the shoulder” following tearing of the acromioclavicular and/or coracoclavicular ligaments a misnomer?
-It is the acromio-clavicular joint which is separated and not the shoulder joint
4 muscles that connect the upper limb to the anterior and lateral thoracic wall
- Pectoralis major
- Pectoralis minor
- Serratus anterior
- Deltoid
Functions of Pectoralis Major
-Major flexor, adductor, and medial rotator of the arm
Functions of pectoralis minor
-protracts, depresses, and stabilized the scapula against thoracic wall
Serratus anterior functions
- protracts and rotates scapula
- stabilizes medial border of scapula against the thoracic wall
Innervation of serratus anterior
-long thoracic nerve
-Deltoid functions
-can flex, extend, or abduct the arm depending which fibers activates
Innervation of anterior compartment of arm vs posterior compartment
- Anterior: musculocutaneous nerve
- Posterior: radial nerve
3 muscles of arm anterior compartment and 1 muscle of posterior compartment of arm
-Anterior: Biceps branchii. Brachialis, Coracobrachialis
Posterior: Triceps Brachii
Biceps brachii function
- flexion of arm
- flexion and suppination of forearm at elbow joint
Brachialis function
-flexion of forearm at elbow
Coracobrachialis function
-flexion of the arm
Triceps brachii function
-major extensor of the arm and forearm
Upper limb is innervated by the brachial plexus, which is formed by an intermingling of ventral rami from the ________ spinal nerves
-C5-T1
Erb-Duchenne Syndrome results from a lesion of what?
-C5 and C6 ventral rami of the superior trunk of the plexus
What musculature is usually affected in Erb-Duchenne Syndrome?
- proximial musculature in the upper limb
- muscles acting at the shoulder and elbow
What infamous position will the upper limb reside in in Erb-Duchenne Syndrome?
- “waiter’s tip position”
- results from a loss of abduction and a weakness of flexion and lateral rotation at glenohumeral joint
- the arm is adducted, extended, and medially rotated
T/F: Rhomboid muscles, levator scapulae muscle, and the serratus anterior muscle are affected in Erb-Duchenne Syndrome.
False; they are unaffected because the nerves that supply these muscles arise from ventral rami proximal to the lesion
Klumpke’s Paralysis results from?
-Compression of the C8 and T1 VR in the inferior trunk of the plexus
Patients with Klumpke’s Paralysis experience weakness of what muscles which results in what clinical manifestations?
- Intrinsic hand muscles innervated by C8 or T1 fibers in the median and ulnar nerves
- results in combination of an ape hand and a claw hand
Patients with Klumpke’s Paralysis may have difficulty performing what task?
-Making a fist
What pathologies may cause Klumpke’s Paralysis?
- cervical rib or Pancoast tumor
- may be in conjunction with other symptoms of thoracic outlet syndrome
List the 10 collateral nerves arising from the roots, trunks, and cords of the plexus
- suprascapular nerve C5,6
- lateral pectoral nerve C5,6,7
- medial pectoral nerve C8,T1
- medial brachial cutaneous nerve C8,T1
- medial antebrachial cutaneous nerve C8,T1
- upper subscapular nerve C5,6
- thoracodorsal nerve C6,7,8
- lower subscapular nerve C5,6
- dorsal scapular nerve C5
- long thoracic nerve C5,6,7
Suprascapular nerve
C5,6
supplies supraspinatus and infraspinatus muscles
lateral pectoral nerve
- C5,6,7
- supplies pectoralis major at mainly its clavicular head
medial pectoral nerve
- C8,T1
- supplies pectoralis minor then passes through it to innervate the pectoralis major
Medial brachial cutaneous nerve
C8,T1
supplies skin on medial aspect of arm
Medial antebrachial cutaneous nerve
C8,T1
supplies skin on medial aspect of forearm
upper subscapular nerve
- C5,6
- supplies upper part of subscapularis muscle
thoracodorsal nerve (middle subscapular nerve)
- C6,7,8
- supplies latissimus dorsi
lower subscapular nerve
- C5,6
- supplies lower part of subscapularis muscle and teres major muscle
dorsal scapular nerve
- C5
- supplies levator scapulae, rhomboid major, and rhomboid minor
long thoracic nerve
- C5,6,7
- supplies serratus anterior muscle
Musculocutaneous nerve
- C5,6, and 7?
- supplies coracobrachialis, biceps brachii, and brachialis muscles
- continues as lateral antebrachial cutaneous to supply skin of lateral aspect of forearm
Median nerve
- C6,7,8,T1
- supplies superficial muscles in anterior forearm, including flexor carpi radialis, palmaris longus, flexor digitorum superficialis, and pronator teres
Medial nerve supplies all muscles in anterior forearm except…
- brachioradial (radial nerve)
- flexor carpi ulnaris and medial half of flexor digitorum profundus (ulnar nerve)
Ulnar nerve
- C8, T1
- innervates flexor carpi ulnaris muscle and medial half of flexor digitorum profundus
Axillary nerve
- C5,6
- innervates deltoid and teres minor and skin covering deltoid
Radial nerve
- C5,6,7,8,(T1)
- innervates 3 heads of triceps brachii, brachioradialis, and extensor carpi radialis longus and skin of posterior arm
Borders of axilla
- Medial: rib cage and serratus anterior
- Anterior: pectoralis major and minor
- Posterior: scapula and subscapularis, latissimus dorsi and teres major
- Lateral: arm
What forms the anterior and posterior axillary fold?
- Anterior: lateral portion of pectoralis major
- Posterior: latissimus dorsi and teres major
The thyrocervical trunk of subclavian artery gives rise to what 2 arteries before continuing on to form the axillary artery?
- Suprascapular artery
- Transverse cervical artery
Suprascapular artery supplies..
-supraspinatus and infraspinatus muscles
Transverse cervical artery supplies…
- its superficial branch supplies the trapezius
- deep branch (dorsal scapular artery) supplies rhomboids and levator scapulae
The axillary artery is divided into 3 parts by the _______.
-pectoralis minor
Superior thoracic artery
- first branch from axillary artery
- supplies first 2 intercostal spaces and serratus anterior
Thoracoacromial artery
-supplies anterior wall of axilla, including pectoralis major and minor, deltoid, clavicle, and acromioclavicular joint
Lateral thoracic artery
- supplies serratus anterior, pectoral muscles, and breast
- courses with long thoracic nerve
Subscapular artery
- largest branch of axillary artery
- gives rise to circumflex scapular artery which supplies teres minor, major, and infraspinatus muscle
- gives rise to thoracodorsal artery which supplies latissimus dorsi
Posterior circumflex humeral artery
- arises adjacent to subscapular artery
- supplies deltoid, teres major and minor, and long head of triceps
Anterior circumflex humeral artery
- smaller than posterior
- supplies muscles in anterior arm
Brachial artery continues from the axillary at lower border of ____________.
- Teres major
- supplies anterior and posterior aspects of the arm
Profunda brachial artery
-supplies triceps brachii muscle and contributes to collateral circulation at elbow
What arises from brachial artery in cubital fossa to supply forearm and hand?
-radial and ulnar arteries
Superficial veins draining hand/arm
-cephalic vein and basilic vein
Where does the cephalic vein arise from and drain into?
- arise from lateral aspect of venous network
- drains into axillary vein
Where does the basilic vein arise from and drain into?
- arise from medial aspect of venous network
- joins with the brachial vein to form the axillary vein
3 pairs of antagonistic muscles of pelvis and thigh
- iliopsoas and gluteus maximus
- posterior femoral group- hamstrings vs. quadriceps femoris
- deep gluteal muscles vs. medial femoral group
All muscles of anterior thigh are innervated by the ________ nerve except for what muscle?
- Femoral nerve
- Psoas major
4 parts of quadriceps femoris
- rectus femoris
- vastus lateralis
- vastus medialis
- vastus intermedius
Roles of rectus femoris vs. vastus muscles of quadriceps
-RF: is only part to cross both hip and knee joint, so it flexes thigh at hip joint and extends leg at knee joint
V: only cross knee joint, so extend leg at knee
Psoas major muscle
- flexes thigh
- innervated by anterior rami of L1 and L2
Iliacus
-flexes thigh in conjunction with psoas major
Sartorius
- crosses both hip and knee joints
- flexes, abducts, and laterally rotates thigh at hip joint
- flexes leg at knee joint
Pectineus
- adducts and flexes at thigh
- assists with medial rotation of thigh
5 muscles of anterior thigh
- quadriceps femoris
- psoas major
- iliacus
- sartorius
- pectineus
Borders of femoral triangle
- superior: inguinal ligament
- medial: adductor longus
- lateral: sartorius
Contents from lateral to medial of femoral triangle
- femoral neve
- femoral artery
- femoral vein
- deep inguinal lymph nodes
Adductor canal extends from…
- aka subsartorial canal
- extends from apex of the femoral triangle to adductor hiatus in tendon of adductor magnus
Purpose of adductor canal
-providers intermuscular passage for femoral artery and vein, saphenous nerve, and nerve to vastus medialis
The adductor canal is bounded anteriorly and laterally by _________ and posteriorly by ________ and medially by __________.
- AL: vastus medialis
- P: adductus longus and adductus magnus
- M: sartorius
Superiorly to the adductor canal, the great saphenous vein pierces the deep fascia of the thigh at an opening in the fascia lata called ________.
- Saphenous opening
- enters this opening to join the deep venous system of the lower limb at femoral vein
What is the longest muscle in the body?
-Sartorius
Proximally in the thigh, the femoral artery gives off what branches?
- medial and lateral circumflex arteries
- deep femoral (profunda femoris) arteries
With one exception (name it), the medial thigh muscles are innervated by what nerve?
- hamstring portion of adductor magnus
- Obturator nerve
Muscles of the medial thigh (5 of them)
- adductor longus
- adductor brevis
- adductor magnus
- Gracilis
- Obturator externus
Adductor longus
-adducts thigh
Adductor brevis
-adducts thigh and slightly flexes thigh
Adductor magnus
- Adductor part: adducts and flexes thigh (obturator n)
- Hamstring portion: extends thigh (tibial part of sciatic n)
Gracilis
-adducts thigh, flexes leg, helps rotate leg medially
Obturator externus
- laterally rotates thigh
- steadies head of femur in acetabulum
Immediately below and contihuous to pectineus is the ________.
-adductor longus
What is the most medial thigh muscle?
-Gracilis
What artery supplies medial and posterior thigh?
-Profunda femoral artery gives rise to 4 perforating arteries which supply medial thigh and pass through adductor magnus to supply the muscles in posterior thigh
Cruciate Anastomosis contributions
- inferior gluteal artery
- medial and lateral circumflex femoral arteries
- first perforating artery
Cruciate Anastomosis is important for collateral circulation if which artery becomes occluded?
-Femoral artery
Popliteal gives rise to 5 genicular arteries which supply ______________.
-Knee joint
Collateral circulation contributors of the knee
- 5 genicular branches of popliteal artery
- descending genicular branch of femoral artery
- descending branch of lateral circumflex femoral artery
- anterior recurrent branch of anterior tibial artery
Where does the obturator artery arise and where does it supply?
- usually arises from internal iliac artery and passes through obturator foramen into medial compartment of the thigh
- supplies obturator externus, pectineus, adductors of thigh, and gracilis
Superficial system of veins of lower limb
. great saphenous
-small saphenous
Great saphenous vein drains into the _______ after passing through the saphenous hiatus, a fault in the fascia lata
-femoral vein
Small saphenous vein drains into the _____________.
-popliteal vein
The musculocutaneous nerve pierces what muscle?
-coracobrachialis
Cutaneous innervation of the median nerve
-lateral 3.5 digits and their corresponding finger tips
Ulnar nerve cutaneous innervation
-medial 1.5 digits and the dorsal side of those digits
Femoral nerve spinal segments
-L2,3,4
Lateral femoral cutaneous nerve spinal cord segments
-L2,3
Spinal cord segments making up obturator nerve
-L2,3,4
Where does the saphenous nerve arise from and what types of fibers does it contain?
- from femoral nerve
- cutaneous only
Spinal segments making up Superior gluteal nerve
-L4, L5, S1
Spinal segments making up inferior gluteal nerve
-L5, S1, S2
Spinal segments making up posterior femoral cutaneous nerve
S1,S2,S3
Spinal segments making up sciatic nerve
-L4-S3
Spinal segments making up common fibular nerve
-L4, L5, S1, S2
Spinal segments making up tibial nerve
-L4, L5, S1, S2, S3
spinal segments making up nerve to obturator internus and superior gemellus
-L5, S1, S2
spinal segments making up nerve to quadratus femoris and gemellus inferior
-L4, L5, S1
Where do lumbosacral nerves exit?
-through the greater foramen
Which nerve is medially and laterally located within the sciatic nerve?
- lateral: common fibular n
- medial: tibial nerve
What bones move in pronation/supination?
- only the radius
What muscles are innervated by the anterior interosseous n and what nerve is this a branch of?
- flexor pollicis longus
- flexor digitorum profundas (lateral 1/2)
- pronator quadratus
- *deep muscles of anterior forearm
- branch of median nerve
What is the deep branch of the radial nerve called?
-posterior interosseous nerve
