Brachial Plexus and Peripheral Nerve Anatomy Flashcards
2 minnesregler for anatomy
RTDCB
Vertikalt:MARMU
How many vertebrae and roots?
C7 vertebrae but c( roots going out over the vertebrae
draw plexus in 20s
C5-T1, and RTDCB. 2 arrows and a straight line in the middle
T: Upper T gives 2 nerves (Supras, Subcl)
R: Dorsal Scapular from C5 + LTN C5-7
D: Strike is better than a spare
C: Lateral 1 LP
Posterior 3 Subscap: sup, mid/TD, inf
Anterior 3 MP,MBC,MABC
B: 2 waves and 1 long wave
MARMU
Trunk names?
Upper (C5-6)
Middle (C7)
Lower (CC8-T1)
Division names
Anterior (ant muscles/preaxillary compartment)
Posterior (postaxillary…)
Cords/fascicles
- Lateral (from Anterior div compartment)
- Posterior (post div)
- Medial (ant fr lower cord)
Relation to axillary artery
M-shape
Lateral and medial cord gives musculocut, lateral root to median n.
Medial cord gives ulnar n and medial root to median n
Nerves from roots?
Dorsoscapular n (C5) Longt Thorasic Nerve C5-7
Nerves from Trunks
Upper trunk:
Suprascap
Subclavius
Nerves from division
None
Nerves from Cords
Lateral: Lat Pectoral n (Communication with med. pect.)
Posterior: Lower, Middle (TD), Upper subscap
Medial: Medial AnteB + Brachial cut n
Medial Pectoral n
Trauma mekanism upper plexus inj
Extreme/violoent lateral flexion + simultaneously depressed shoulder
Or oblique force pushing arm and head in opposite direction
Shoulder dystocia, MC accident falling on shoulder
C5-6 inj called?
Symtoms?
Muscles affected?
Erb-Duchene paralysis
- arm hangs limply at the side internally rotated
- Pronated forearm (Waiters tip position)
Deltoid, supra/infraspinatus, biceps, brachialis, m. supinator
Rhomboids, levator scapulae, Serratus ant if avulsion
Lower Brachial plexus inj
- trauma mechanism?
- eponym?
- symtoms?
Extreme abduction; holding on to at three falling or delivery pulled by the arm
Klumpke´s paralysis - partial lower plexus injury
Clawing, supinated extended wrist
Intrinsic minus hand ulnar FDP + FCU weakness, , C8 +T1 numbness, T1 injury may give Horner syndrome (mitosis, ptosis)
C8-T1 calles
Klumpkes paralysis
Claw hand
Serratus anterior innervation
Long Thoracic Nerve
(protracts and upperly rotates scapula. Keeps the scapula tight against the thoracic cage during arm movement)
Axillary nerve innervates
- Deltoid (ant->flex, mid->abd, post->ext)
- T minor (ext rotation)
+ upper brachial lateral cutaneous nerve (post surface)
Through Quadrangular space
Radial nerve course?
Post chord, Triangular interval, dorsal radial groove, lat intermuscular septum, between BR/Brachialis, lat epicondyle, cubital fossa, divides, between supinator 2 heads/frohses arcade after division. Followed by a. profunda brachi. Superficial branch goes deep to BR and out subcutaneous 9cm prox to wrist between BR/ECRL.
(Ext kompartment (all) + dorsolat. skin arm + BR + Sup)
Tri, Post. Cut., Inferior lateral cut, post/lat antecbrachi cut, Anc, BR, ECRL
Deep branch: ECRB, Sup ->PIN (after sup): EDC, EDM, ECU, APL, EPB, EPL, EIP
Sup branch: skin
Musculocutanous nerve
Flexor compartment
1. Coracobrachialis (shoulder flex + add shoulder)
2. Brachialis (flex elbow)
3. Biceps brachi (flex + sup)
+ LABCN Lateral Antebrachial Cutaneous Nerve
Ulnar nerve innervation?
- FCU
- 1/2 FDP
- Sens ulnar 1/3 of hand
- Hypothenar muscles
- All intrinsic hand muscles incl deep FPB head except:
- Thenar, 1st two lumbricals,
Median nerve innervation?
Branches: PT, FCR, PL, FDS, AIN (under PT), palmar skin branch, motorbranch to thumb, digital nerves
AIN: radial 1/2 FDP, FPL, PQ
Motor branch to thumb: LOAF
- *L**ateral 2 lumbricals
- *O**pponens
- *A**bductor pollicis brevis
- *F**lexor pollicis brevis (superficial head)
AIN (along interosseous membrane)
All flexor muscles except FCU + 1/2 FDP
Recurrent branch of median nerve (thenar motor)
Sens
Dorsal scapular nerve
c5!
Rhomboids (Maj + min)+ lev scapula
Suprascapular nerve
Upper trunk
Supraspin, infraspin, shoulder joint
Subclavius
upper trunk
subclavius m
superis clavicle
