MindMap Gallery Anatomy Deep Dive: Muscles of the Pectoral Region Explained
Discover the intricate anatomy of the pectoral region, including the pectoralis major and minor, and their connections to movements and nerve supply. This detailed exploration provides essential knowledge for students, medical professionals, and fitness enthusiasts interested in the biomechanics and function of chest muscles.
Edited at 2022-03-24 22:15:27The arm is a complex structure composed of bones, muscles, nerves, blood vessels, and other tissues. Understanding the anatomy of the arm is essential for medical professionals and anyone interested in the human body. Here's an overview of the key anatomical components of the arm.
Discover the intricate anatomy of the pectoral region, including the pectoralis major and minor, and their connections to movements and nerve supply. This detailed exploration provides essential knowledge for students, medical professionals, and fitness enthusiasts interested in the biomechanics and function of chest muscles.
Dive deep into the anatomy of the axilla with our detailed guide, highlighting the complex structure of the armpit and its significance in the human body. Explore the various walls of the axilla, the important blood vessels, nerves like the brachial plexus, and the lymph nodes critical for immune response. This guide is essential for medical students, healthcare professionals, and anatomy enthusiasts interested in the intricacies of human anatomy and the pivotal role of the axillary region.
The arm is a complex structure composed of bones, muscles, nerves, blood vessels, and other tissues. Understanding the anatomy of the arm is essential for medical professionals and anyone interested in the human body. Here's an overview of the key anatomical components of the arm.
Discover the intricate anatomy of the pectoral region, including the pectoralis major and minor, and their connections to movements and nerve supply. This detailed exploration provides essential knowledge for students, medical professionals, and fitness enthusiasts interested in the biomechanics and function of chest muscles.
Dive deep into the anatomy of the axilla with our detailed guide, highlighting the complex structure of the armpit and its significance in the human body. Explore the various walls of the axilla, the important blood vessels, nerves like the brachial plexus, and the lymph nodes critical for immune response. This guide is essential for medical students, healthcare professionals, and anatomy enthusiasts interested in the intricacies of human anatomy and the pivotal role of the axillary region.
muscles of the pectoral region
pectoralis major
origin
by two heads
Sternocostal head:
anterior surface of the sternum.
Upper 6 costal cartilages.
External abdominal oblique aponeurosis.
clavicular head:
from anterior surface of the medial 1/2 of the clavicle.
nerve supply(double)
Lateral and medial pectoral nerves.
insertion
The upper fibers are twisted and inserted downward forming the anterior lamina.
The lower fibers are twisted and inserted upward forming the posterior lamina.
actions
Adduction and medial rotation of the arm.
Flexion of the arm by clavicular head.
Elevates the ribs during deep inspiration.
Sternocostal part acts together with latissimus dorsi, teres major and deltoid: draw the trunk up during climbing and gymnastic.
subclavius
origin
from the upper surface of first rib and first costal cartilage
insertion
into subclavian groove on the lower surface of the clavicle
nerve supply
nerve to sublcavius from upper trunk of brachial plexus ( C 5&6)
action
fixation of the clavicle during movments of the shoulder girdle
serratus anterior
origin
by fleshly digitations from the upper eight ribs.
The first digitation takes origin from the 1st and 2nd ribs.
insertion
anterior surface of the medial border of the scapula.
a) The first digitation: anterior surface of the superior angle
b)The 2nd and 3rd digitations: anterior surface of medial border
c)The lower five digitations: anterior surface of inferior angle
nerve supply
long thoracic nerve (nerve of Bill C5, 6, &7) passes superficial to the muscle
actions
Protraction of the scapula (pulls the scapula forward with pectoralis minor)
Lower 5 digitations, Abduction of the arm above 90 degree,acting with the trapezius muscle
Fixation of the scapula during movement of the upper limb
pectoralis minor
origin
from the 3rd,4th and 5th ribs
insertion
superior surface of the coracoid process
nerve supply
medial pectoral nerve
actions
protraction the scapula (forward movment)
depression the shoulder
elevates the ribs during deep inspiration
please check out slide 13 ***
d) Lymphatics vessels
c) Lateral pectoral Nerve
b) Thoraco-acromial Artery
a) Cephalic Vein
The structures pierced the fascia:
Attachments:
4- Laterally, the coracoid process.
3- Medially, the first rib.
2- Inferiorly, it splits to enclose pectoralis minor, then fuse together to form suspensory ligament of the axilla. It attaches to the axillary fascia
1- Superiorly, it splits into two laminae which enclose subclavius and attached to the margins of subclavian groove.
• Clavipectoral Fascia
• Test of the muscle: ask the patient to push the wall with the outstretched hand. If the muscle is affected the winging is increased
• A protrusion of the medial border of the scapula away from the posterior chest wall.
• Winging of the scapula, due to paralysis of the muscle
• It descends in the midaxillary line on the superficial surface of the muscle
Injury of the long thoracic nerve
Deltopectoral groove between deltoid and pectoralis major containing: 1- Cephalic Vein.2- Deltoid branch of thoracoacromial Artery.
It is the only muscle of the upper limb supplied by 5 segments from brachial plexus.
SO the anterior fold of the axilla is higher than the posterior fold
Pectoral region is the region in front of the upper part of the chest, its Muscles connecting the chest wall to the arm