Upper Limb Nerves By: Rameez and Kashif
NERVES
Axillary
C5C6
Musculocutaneous C5C7
Median C5T1
Ulnar C8T1
Radial C5T1
SENSORY SUPPLY
Lateral Arm
Lateral Forearm
Lateral 3 ½ digits : Lateral Palm
Medial 1 ½ digits : Medial Palm. Medial Forearm
Dorsum of hand over 1st web and anatomic snuffbox. Posterior arm and forearm
MOTOR FUNCTIONS
Deltoid Abduct Shoulder 15 110 degrees. Teres Minor Lateral rotation of shoulder
All the muscles of Anterior Compartment of Arm. BBC Bracialis , Biceps Brachii , Coracobracialis. > Flex Elbow >Supination (Biceps)
A. Forearm: All the muscles in the Anterior Compartment of forearn except 1 ½ muscle by ulnar nerve (flexor carpi unlaris and ulnar half of flexor digitorum profundas) > Flex wrist and All digits > Pronation Hand : 1,2 LOAF
1st n 2nd Lumbricals(Digit 2&3) >Flex MCP and Extend PIP & DIP
A. Forearm Anterior Compartment : 1 ½ muscle not supplied by the median nerve Flexor Carpi Ulnaris and Ulnar half of the Flexor Digitorum Profundus . > Flex wrist ( weak ) and Digits 4 and 5. Hand : 3,4 LOAF
3rd & 4th Lumbricals Hypothenar Muscles ( OAF digiti minimi )
Posterior Compartment Muscles of the Arm and Forearm. >Extend MCP , wrist and elbow Joints. > Supination (Supinator muscle )
Thenar Compartment Oppoonens Pollicis (thumb opposition) , Abductor Pollicis brevis , Flexor Pollicis Brevis
All interossei (DAB + PAD ) >also assist lumbricals in digits 25. Adductor Pollicis (thumb adduction)
MANI FESTATION OF INJURY
Adduction & Medial Rotation Loss of sensation of lateral arm.
Extended elbow and Pronated forearm.
*Weakened wrist flexion with ulnar deviation
*Loss of pronation *Absence of flexion at Lat. 3 digits “ hand of benediction * Loss of thumb opposition “ape hand” * Loss of 1st 2 lumbricals *thenar atrophy *loss of sensation over thenar eminance and dorsal and palmar aspects of lateral 3.5 fingers with proximal lesion. Median Claw(Extending Digits)
*Weakened wrist flexion with radial deviation
* Loss of hypothenar muscle ( atrophy ), 3rd & 4th lumbricals ( weak interphalengeal extension ), all interossi ( loss of abduction and adduction of digits 25 ) Adductor pollicis ( loss of thumb adduction ). Loss of sensation over medial 1.5 fingers including hypothenar eminance. Ulnar Claw (on extending fingers) *Always remember that the distal lesion will cause problems in extending the fingers. Proximal lesions will prevent in Flexing the Fingers.
Loss of extension at the MCP ,wrist and elbow . Weak or no supination Decreased grip strength (wrist extension necessary for maximal action of flexors). Loss of sensation over arm,forearm and dorsal hand and dorsum of thumb. Wrist Drop
Ape hand and Pope’s Blessing (on making fist)
CAUSES O F INJURY TO NERVES
Surgical Neck Fracture of Humerus
Anterior Dislocation of Humeral head
Erbs palsy: (When Axillary, Musculocutaneous and Suprascapula nerves are all injured)
Upper trunk Compression
Erbs Palsy: (When Axillary, Musculocutaneous and Suprascapula nerves are all injured)
s
Carpal Tunnel Compression
Supracondylar fracture of humerus
Pronator teres syndrome
Dislocated lunate
Fracture of medial epicondyle of humerus
Fracture of hook of hamate
fracture of clavicle
Klumpke`s palsy: Total Claw Hand
Saturday night palsy
Midshaft fracture of humerus
Sublaxation of radius
Dilocated humerus