Human Anatomy Vol 1

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UPPER LIMB

The deep fascia covering the pectoralis major muscle is
called the pectoral fascia. It is thin and closely attached
to the muscle by numerous septa passing between the
fasciculi of the muscle. It is attached superiorly to the
clavicle, and anteriorly to lhe sternum. Superolaterally,
it passes over the infraclavipular fossa and deltopectoral

groove to become continuous with the fascia covering
the deltoid. lnferolaterally, the fascia curves round the
inferolateral border of the pectoralis major to become
continuous with the axillary fascia. lnferiorly, it is
continuous with the fascia over the thorax and the
rectus sheath.

Dissection

ldentify the extensive pectoralis major muscle in the
pectoral region and the prominent deltoid muscle on
the lateral aspect of the shoulder joint and upper arm.
Demarcate the deltopectoral groove by removing the
deep fascia. Now identify the cephalic vein, a small
artery and few lymph nodes in the groove.
Clean the fascia over the pectoralis major muscle
and look for its attachments. Divide the clavicular head
of the muscle and reflect it laterally. Medial and lateral
pectoral nerves will be seen supplying the muscle.
Make a vertical incision^5 to^6 cm from the lateral
border of sternum and reflect its sternocostal head
laterally.
ldentify the pectoralis minor muscle under the central
part of the pectoralis major. Note clavipectoral fascia
extending between pectoralis m,inor muscle and the
clavicle bone.
ldentify the structures piercing the clavipectoral
fascia: These are cephalic vein, thoracoacromial artery
and lateral pectoral nerve. lf some fine vessels are also
seen, these are the lymphatic channels.
Also, identify the serratus anterior muscle showing
serrated digitations on the side of the chest wall.

Introduction
Muscles of the pectoral region are described in
Tables 3.1 and 3.2. Some additional features are given
below.

Peclorolis Mojot

a. Bones and cartilages; Sternum, ribs, and costal
cartilages.
b. Fnscia: Clavipectoral.
c. Muscles: Subclavius, pectoralis minor, serratus
anterior, intercostals and upper parts of the biceps
brachii and coracobrachialis.
d. Vessels: Axillary.
e. Neraes: Cords of brachial plexus with their branches.

The muscle is inserted by a bilaminar tendon into the
lateral lip of the intertubercular sulcus of the humerus.

Supraclavicular

lnternal mammary
Humerus Opposite
breast

Fig. 3.16: Lymphatic spread of breast cancer

Vertebral body lnferior vena cava
Venous
plexus
within
veftebral
body Anterior vertebral part venous of externalplexus

Basivertebral vein

Segmental vein
Dura mater
Epidural plexus

Posterior part of
external vertebral
venous plexus

Fig. 3.17: Veftebral system of veins
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