Arm Anatomy And Ulnar Nerve Transposition

Front 1

Nerve conduction that will likely need operative management

Back 1

<40 m/sec

Front 2

Simple decompression:

Back 2

Simple decompression:
IV anesthetic and 6-10cm incision along the course of the ulnar nerve midway between medial epicondyle and olecranon. Avoid injury to medial antebrachial cutaneous nerve.
Most Superficial Layer of Volar Forearm Muscles:
Brachioradialis from lateral epicondyle
Pronator teres from superior aspect of medial condyle
From common flexor tendon radial to ulnar: FCR, Palmaris Longus, FCU

Front 3

How do the nerves cross the elbow:

Back 3

Median: Anterior to Medial Epicondyle
Radial: Anterior to Lateral Epicondyle
Ulnar: Posterior to Medial Epidcondyle
Musculocutaneous: anterior to belly of brachialis (deep to biceps brachii, with Brachial artery)

Front 4

Describe the arteries around the elbow

Back 4

Brachial artery runs antecubital between biceps brachialis and bracialis with musculocutaneous nerve
Brachial artery divides into radial and ulnar arteries
Ulnar artery first gives off anterior recurrent ulnar artery, then common interosseous artery (which will divide into A&P IO A’s) and then posterior ulnar recurrant artery.

Front 5

Where does the radial artery run in the forearm

Back 5

Deep to brachioradialis, superficial to supinator, pronator teres, fds, and fpl

Front 6

When does the AIN split off of the median nerve? Where does it run?

Back 6

Early in forarm, immediately past proximal pronator terres
Runs with Anterior IO Artery (From Common IOA, from Ulnar A from Brachial A) deep to FPL and FDS

Front 7

Between what structures is the median nerve found in the proximal forearm

Back 7

Deep to FDS but superficial and nestled between FDP and FPL

Front 8

What vessel runs with the radial nerve as it comes around the elbow

Back 8

Recurrent radial artery on its way back to the Deep Brachial Artery (please confirm)

Front 9

Where does the Radial nerve divide into deep and superficial

Back 9

Divided by supinator immediately distal to elbow

Front 10

Which is superficial FDS or FPL

Back 10

FDS; FPL can be thought of as being the same level as FDP (Deep muscles)
NB: FCU is deep to FDS, but visible as a superficial muscle due to its medial position

Front 11

Basalic and Cephalic Ceins:

Back 11

Basilic is medial; Cephalic is lateral and runs with lateral antebrachial cutaneous nerve (from musculocutaneous nerve)

Front 12

Where does pronator teres attach:

Back 12

Superior aspect of medial humeral condyle as well as an ulnar head which attaches medial to the coranoid

Front 13

What makes up the common flexor tendon:

Back 13

Pronator teres (also has individual humeral head attachments), FCR, Palmaris Longus, FCU, FDS (also has heads for ulnar and radial attachments)

Front 14

What two structures does the radial artery run between in the distal forearm

Back 14

Extensor carpi radialis and flexor carpi radialis

Front 15

lateral antebrachial cutaneous nerve – what does it come from and where does it run?

Back 15

Terminal branch of musculocutaneous nerve
Emerges laterally from space superficial to brachialis and deep to biceps
Runs superficial to brachioradialis with cephalic vein

Front 16

What wraps nicely around the flexor muscle mass?

Back 16

Bicepital aponeurosis

Front 17

What nerve runs along with the brachial artery in the upper arm?

Back 17

Median

Front 18

With what artery does the median nerve run in the forearm?

Back 18

None
Well that’s not true. After Ulnar nerve comes up from beneath pronator teres and median nerve come down from over pronator teres they join together for a little while, but the ulnar artery courses across FDP (beneath FDS) to go join ulnar nerve, leaving the median nerve all alone.

Front 19

AIN Artery and Nerve – Whence Cometh?

Back 19

AIOA from Common IOA from Ulnar A from Brachial A (other division of Brach is Radial)
AIN from median nerve
Ulnar Artery & AIOA run inferior to pronator teres
Median Nerve & AIN run superior to pronator teres

Front 20

What is the course of the median antebrachial vein

Back 20

Drains palmar venous system, runs proximally on the volar/ulnar aspect of forearm. Usually ends in bailic vein or Median cubital vein

Front 21

Median cubital vein

Back 21

Vein, superficial even to the biceps aponeurosis which connects basilica with cephalic ceins

Front 22

Origin of Cephalic vs Basilic Veins:

Back 22

Basilic: colelcts from the ulnar side of the dorsum of hand, cephalic from the most medial side. NB: Median antebrachial vein collects palmar hand.

Front 23

Deep AND Superficial muscles of the extensor forearm from radial to ulnar

Back 23

Weirdos: Extnsor Capri Radialis Longus and ECRB (attached at common extensor site) are intereting because they start out as more superficial then dive deep beneath APL and EPB

Extensor Digitorum, Extensor Digiti Minimi, Extensor Carpi Ulnari (immediately adjacent to flexor carpi ulnaris)
Deep: (Supinator which dives deep to ECRB) APL, EPB, EPL, Extensor Indicis

Front 24

Where do the PIN and PIA run relative to the muscles?

Back 24

Between the Superficial (ED, EDM, ECU) and Deep (APL, EPB, EPL, EI) Muscular Layers of the Extensor Compartment

Front 25

Alright lets try to make some menumonitics for the Brachial Plexus becoming terminal branches

Back 25

PAR: Posterior becomes axillary and Radial
MUM: Medial becomes Ulnar and Median
LMM: Lateral becomes Musculocutaneous and Median
MLM: Median is from Medial and Lateral

Front 26

Profunda brachii:

Back 26

Dives posteriorly via inferior to teres major, deep to triceps between long and short heads (triceps hiatus) with radial nerve in radial groove until it pierces lateral intermuscular septum and descends between brachialis and biceps brachialis before becoming/anastomosing with recurrent radial artery

Front 27

What nerve runs with the brachial artery in the upper arm?

Back 27

Median, and medial Brachial Cutaneous all seem to run with artery together
Ulnar chills with it proximally, but then gets left behind in the posterior compartment while all the cool kids migrate anteriorly

Front 28

What arteries run around the elbow and what do they anastamose between

Back 28

First off Brachial artery is head honcho
Anterior and Posterior Ulnar Recurrent Arteries
Anterior returns just lateral to trochlea, but anterior to medial epicondyle and becomes inferior ulnar collateral artery (joins brachialis distally)
Posterior URA runs posterior to ulna, posterior to medial epicondyle (with ulnar nerve) and joins brachial artery proximally
Recurrent Radial Artery becomes Deep Brachial Artery: ascends with radial nerve, including joining it in the spiral groove
Recurrent IO Artery becomes Middle Collateral artery

Front 29

Fromont’s sign:

Back 29

Cannot hold onto paper between thumb and index except with AIN tip to tip pinch

Front 30

What Cervical levels is the ulnar nerve representative of:

Back 30

C8 & T1

Front 31

Where does the ulnar nerve run in the upper arm:

Back 31

posteromedial to the brachial artery, posterior to the intermuscular septum, anterior to the medial head of the triceps muscle

Front 32

Where does the medial intermuscular septum of the humerus start and end?

Back 32

Continuous band from coracobrachialis muscle to medial epicondyle

Front 33

Arcade of Struthers

Back 33

band of deep brachial fascia that attaches to IM septum and covers ulnar nerve approximately 8 cm proximal to medial epicondyle

Front 34

What nerve is associated with the ulnar nerve at the elbow:

Back 34

medial antebrachial cutaneous nerve passes posterior to ulnar nerve at or proximal to epicondyle

Front 35

Define the cubital tunnel

Back 35

fascial layer extending from flexor carpi ulnaris and arcuate ligament of Osborne (between the two heads of the FCU the humeral and ulnar)

Front 36

Special relationship between FCU and ulnar nerve:

Back 36

ulnar nerve runs between the muscle’s ulnar and humeral heads beneath the arcuate ligament of Osborne which connects the two

Front 37

Where can the ulnar nerve be compressed at the elbow?

Back 37

Arcade of struthers, the IM septum, the FCU fascia, the ancoenus epitrochlearis, Osborne’s ligament, fascial bands within FCU distally

Front 38

In situ decompression:

Back 38

6-10 cm incision along the course of ulnar nerve midway between medial epicondyle and olecranon
NB: avoid/protect MABC nerve
Deep branch of MABC crosses the incision about 3.5 cm distal to medial epicondyle
Proximal branch crosses 1.5 cm proximal to medial epicondyle and often runs with intramuscular septum
Identify IM septum proximally and find the ulnar nerve beneath it – decompress from well above medial epicondyle through cubital tunnel.
Expose between FCU heads and release leading tendinous edge of FCU
Run elbow thru ROM to assure no compression
If subluxattes: consider transfer

Front 39

Subcutaneous anterior transposition:

Back 39

Start like in situ, but extend the incision to 15 cm to accommodate transposition .
Be sure to protect MABC branches
Follow ulnar nerve through FCU, preserve motor branches to FCU and FDP
Carefully lift nerve from bed with accompanying longitudinal vascular supply, ligating segmental feeding vessels, neurolysis of motor branches to keep it mobile.
Inspect to make sure its free for real
Anchor it anteriorly by tacking subcu tissue to fascia or elevate a small flap of flexor-pronator fascia based on the medial epicondyle and sew it to overlying dermis to create a barrier.x

Front 40

Intramuscular transposition:

Back 40

Same as subcutaneous transposition except that a groove is dissected into muscle in line with new nerve course. 3 weeks of immobilization and do not allow unrestricted activity until 10 weeks.
Detractors site: potential compromise of flexor-pronator muscle strength and increased scarring