Anatomy

Question 1

Describe the rotator cuff muscles. Attachments, innervations, and actions. What happens with injury to the rotator cuff?

Answer 1

Rotator cuff muscles are:
-Supraspinatus: O-Supraspinous fossa of scapula; I-greater tubercle of humerus; Fxn: Abduction; Innervation- Suprascapular n.
-Infraspinatus: O-infraspinous fossa of scapula; I-greater tubercle of humerus; Fxn: ext. rotation and stabilize; Innervation-Supraspcapular n.
-Teres minor: O-lateral border of scapula; I-greater tubercle of humerus; Fxn: ext. rotation and stablize; Innervation-axillary n
-Subscapularis: O-Subscapular fossa; I-lesser tubercle of hermus; Fxn: internal rotation; Innervation - Upper and Lower subscapular n.
They make up the muscles of the shoulder and are involved with rotating the shoulder.
The most commonly injured muscle is the supraspinatus muscle of the 4 usually d/t repetitive use or in elders when they strain to open a stuck window.
Injury will cause pain when trying to reach overhead.
Pain can be acute or chronic and multiple tests can be used to test the injury.

Question 2

Brachial plexus: understand the components and how they are formed. Know the terminal branches. What muscle group does each terminal branch innervate?

Answer 2

Musculocutaneous nerve: Anterior flexor Arm Compartment (Bicep brachii, brachialis, corcaobrachialis)
Axillary nerve: deltoid and teres minor (C5-C6)
Median nerve: flexor compartment of forearm, thenar mm, lumbricals 1 & 2
Radial nerve: all extensors of the arm and forearm
Ulnar nerve: supplies flexor carpi ulnaris, FDP tendons 3 & 4, rest of intrinsic hand mm

Question 3

Injury to superior trunk?
Injury to inferior trunk?
Injury to posterior cord?

Answer 3

Superior: C5 and C6 affected but ventral rami and dorsal scapular nerve is not affected; motorcyle horse riding, baby pulled too hard during delivery.
Erb Duchenne palsy and hand hangs medially rotated.
Inferior: Kumpke paralysis d/t ulnar nerve; usually d/t grabbing tree limb when falling or child birth pulled on UE
Posterior cord: C5-T1 affected; poorly fitting crutches
cx Saturday Night palsy - radial nerve affected: not able to extend elbow, wrist, fingers, thumb cxing “wrist drop”

Question 4

Cubital fossa boundaries and contents.

Carpal tunnel boundaries and contents.

Answer 4

Cubital fossa: between epidcondyles, brachioradialis, prontator teres

floor: supinator, brachilias
roof: bicipital aponeurosis
contents: biceps brachii tendon, brachial artery, median nerve, radial ulnar aa, superficial vv

carpal tunnel: flexor retinaculum attached to:
scaphoid and trapezium (laterally)
pisiform and hook of hamate (medially)
has 9 flexor tendons and median nerve.

Question 5

Muscles for elbow:

pronation, supination, flexion, extension and nerves?

Answer 5

pronation: pronator teres-median n; pronator quadratus-median n.
supination: supinator - radial n
flexor: bicep brachii - musculocutaneous n
extension: tricep - radial n

Question 6

Lumbosacral plexus - components and how they are formed. Motor branches and which muslce compartments they innervate.

Answer 6

lumbar: L1-L3, superior L4
sacral: lumosacral turnk (inf L4 and L5) + S1 and S4.
obturator: adductor m of thigh, med rotation of hip
femoral: anterior motions of hip an dknee
sciatic: posterior thign, leg, adn sole of foot
superior and inferior gluteal

Question 7

Common fibular nerve injury?
What are causes?
What muscles are affected?
What can actions are lost?
Superior gluteal nerve injury?
What is positive trendelenberg sign?

Answer 7

• Superficial peroneal n – lateral compartment (loss of eversion)
• Deep peroneal n – anterior compartment (loss of dorsiflexion)
o Paralysis of anterior and lateral compartments of the leg
o “Foot drop” due to loss of dorsiflexion & eversion
o “Steppage gait” – raise foot to clear ground
o Affects the gluteal medius m and gluteus minimus m
• When standing on one leg, weak side = pelvis drops on unsupported leg

Question 8

What muscles adducts thigh?
abducts thigh?
flex thigh?
extend thigh?
flex knee?
extend knee?
invert foot?
evert foot?
plnatarflex
dorsiflex
support medial longitudinal arch of foot
nerves?

Answer 8

adducts thigh: obturator n.
-adductor magnus
-adductor brevis
-adductor longus
-gracilis
abducts thigh: *superior gluteal n.
-gluteal minimis
-gluteal medias
flex thigh: *femoral n. 
-pectineus
-iliopsoas
-sartorius
extend thigh:
-gluteus maximus*inferior n. 
flex knee:
-semitendinosus*tibial div sciatic n.
-semimebranosis*tibial
-bicep femoris *long head:  tibial div sciatic n.; short head: common fibular div sciatic n 
extend knee: *femoral n
-quadriceps femoris
invert foot:
-tibialis anterior*deep fibular 
-tibalis posterior *tibial n.
evert foot: *superficial fibular
-peroneus longus 
-peroneus brevis 
plantarflex: *tibial
1. Gastrocnemius 
2. Soleus
3. Plantaris 
dorsiflex: *superifical fibular 
1. Tibial Anterior *deep fibular 
medial longitudinal arch of foot: *tibial
-tibalis posterior

Question 9

Normal and abnormal curvature of spine

Answer 9

Kyphosis
Abnormal convex posteriorly 
•	Humpback 
•	Elder female > male
Lordosis
Abnormal concave posteriorly
•	Either cervical or lumbar region
•	Happens when person gains abdominal weight (getting fat or pregnancy)
Scoliosis	
Abnormal sideway curvature
•	Can be fixed surgically
•	Puberty female > male

Question 10

Muscles in the suboccipital region?
Make up the suboccipital triangle?
Innervation?
In the suboccipital triangle?

Answer 10

• rectus capitis posterior major, minor and obliquus inferior and superior
• rectus capitis posterior major and obliquus inferior and superior
• suboccipital n
• vertebral artery and suboccipital nerve