Lecture 26 Axilla and Breast Flashcards
What is the axilla?
- the axilla is essentially the region that we think of as the deep compartment of the armpit
Where is the axilla located?
- inferior to the glenohumeral joint at the junction of the arm and thorax
Is the axilla an important passageway for neurovascular structures?
- yes
What is the shape of the axilla?
- pyramid shaped
What types of fascia does the axillary region contain?
- superficial and deep
What is significant about the fascia of the pectoral region?
- consists of superficial and deep layers that define borders, invest muscles, and create potential spaces
What nerves travel through the superficial fascia?
- supraclavicular nerves (C3 and C4 spinal nerves)
- anterior and lateral branches of intercostal nerves
What muscle is contained in the superficial fascia of the axilla?
- platysma muscle
- (muscle over lower mandible, neck and upper thoracic/shoulder region; a very superficial skeletal muscle that is mostly subcutaneous)
What fascias are considered deep?
- pectoral fascia
- axillary fascia
- clavipectoral fascia
- deltoid fascia
What does the pectoral fascia do?
- attaches to clavicle and sternum; invests pectoralis major muscle; continous with fascia of anterior abdominal wall
What fascia will become the axillary fascia?
- pectoral fascia
What fascia forms the floor of axilla?
- axillary fascia
What fascia is deep to the pectoralis major muscle?
- clavipectoral fascia
What connects the subclavius muscle and pectoralis minor?
- costocoracoid membrane
What fascia is the costocoracoid membrane a part of?
- clavipectoral fascia
what becomes the suspensory ligament of axilla?
- clavipectoral fascia
What does the clavipectoral fascia do?
- invests subclavius and pectoralis minor muscles
- attaches to clavicle
- becomes suspensory ligament
What are the features of the deltoid fascia?
- attaches to clavicle, acromion, and spine of scapula
- continous with pectoralis fascia
- compartmentalizes scapular muscles
What does the suspensory ligament of axilla connect?
- the axillary fascia and clavipectoral fascia
What are the borders of the clavipectoral triangle?
- deltoid (lateral)
- pectoralis major (medial)
- middle 1/3 of clavicle (superior)
What is the function of the clavipectoral triangle?
- allows passage of neurovascular structures between axilla and pectoral region
What does the clavipectoral triangle contain?
- cephalic vein
- deltopectoral lymp nodes
- deltoid branch of thoracoacromial artery (from axillary a.)
What is the superior boundary of the axillary?
- clavicle
What are the walls of the axilla?
- apex (clavicle)
- lateral wall (shoulder joint/arm)
- base (fossa/armpit)
- medial wall (ribs)
What makes up the apex of the axilla?
- clavicle
- scapula
- 1st rib
What does the apex contain?
- the cervicoaxillary canal
What is the passageway for neurovascular structures from the neck to the upper limb?
- the cervicoaxillary canal
what makes up the base of the axilla?
- skin and superficial fascia (axilla fossa aka armpit)
- anterior axillary fold (lateral border of pec. major muscle)
- posterior axillary fold
- chest wall