Human Anatomy Vol 1

Klumpke's Porolysis

Site of injury: Lower trunk of the brachial plexus.

Cause of injury: Undue abduction of the arm, as in

clutching something with the hands after a fall from a

height, or sometimes in birth injury.

Nerae roots inoolued; Mainly T1 and partly C8.

Muscles

o Intrinsic muscles of the hand (T1).

o Ulnar flexors of the wrist and fingers (C8).

Deformity and position of the hand. Claw hand due to

the unopposed action of the long flexors and extensors

of the fingers. In a claw hand there is hlperextension

at the metacarpophalangeal joints and flexion at the

interphalangeal joints.

Disability

. Complete claw-hand (Fig. a.U).
o Cutaneous anaesthesia and analgesia in a narrow
zone along the ulnar border of the forearm and hand.
o Horner's symdrome if T1 is injured proximal to white
ramus communicans to first thoracic sympathetic
ganglion (Fig. a.13). There is ptosis, miosis, alhydrosis,
enophthalmos, and loss of cilio-spinal reflex-may
be associated. This is because of injury to syrnpathetic
fibres to the head and neck that leave the spinal cord
through nerve T1 (Fig. a.18).
o Vasomotor changes: The skin area with sensory loss
is warmer due to arteriolar dilation. It is also drier
due to the absence of sweating as there is loss of
sympathetic activity.
o Trophic changes: Long standing case of paralysis
leads to dry and scaly skin. The nails crack easily
with atrophy of the pulp of fingers.

Injury to the Nerve to Serrotus Anlerior (Nerve of Bell)

Causes

L Sudden pressure on the shoulder from above.
2 Carrying heavy loads on the shoulder.

AXILLA

Fig. 4.18: Horner's syndrome

D rmity: Winging of the scapula, i.e. excessive

prominence of the medial border of the scapula.

Normally, the pull of the muscle keeps the medial

border against the thoracic wall.

Disahility

. Loss of pushing and punching actions. During
attempts at pushing, there occurs winging of the
scapula (see Fig. 2.72).
o Arm cannot be raised beyond 90o, i.e. overhead
abduction is not possible as it is performed by the
serratus anterior muscle.

Mnemonics

Axillary artery branches "Slap The Lawyer Save

Patient":

'lst part gives (^1) branch; 2nd part 2branch; and 3rd
part (^3) branches.
Superior thoracic branch of 'lst part
Thoracoacromial branch of 2nd part
Lateral thoracic branch of 2nd part
Subscapular branch of 3rd part
Anterior circumflex humeral branch of 3rd part
Posterior circumflex humeral branch of 3rd part
Thoracoa,cromial artery branches ,ABCD':
Acromial
Breast (pectoral)
Clavicular
Deltoid
Brachial plexus branches: "My Aunt Ragged My
Uncle':
From lateral to medial:

. Musculocutaneous
. Axillary
. Radial
. Median
. Ulnar
Brachial plexus "Really Tired Drink Coffee Now":
Roots (ventral rami) Cs-T.l
Trunks (upper, middle, lower)
Divisions (3 anterior and 3 posterior)
Cords (lateral, posterior, medial)
Nerves (branches)

ll

E

=o

CL

CL

f

.9

oo)

Fig. 4.17: Complete claw-hand a