Editing Axilla (section)

===Boundaries===
Anatomically, the boundaries of the ''axilla'' are:

{| class="wikitable"
|  ||  ''superiorly'': by the outer border of [[first rib]], superior border of [[scapula]], and posterior border of [[clavicle]]<ref name="titleAnaesthesia UK :AnaesthesiaUK: Applied anatomy for upper limb blocks">{{cite web|url=http://www.anaesthesiauk.com/article.aspx?articleid=100359 |title=Anaesthesia UK :AnaesthesiaUK: Applied anatomy for upper limb blocks |access-date=2007-12-23 |url-status=usurped |archive-url=https://web.archive.org/web/20081016012019/http://www.anaesthesiauk.com/article.aspx?articleid=100359 |archive-date=2008-10-16 }}</ref> ||
|-
| ''medially'':  [[serratus anterior muscle|serratus anterior]]<ref name="titleLAB #4 PECTORAL REGION & Introduction to the Axilla">{{cite web |url=http://anatomy.iupui.edu/courses/gross-D501/Lab%20Instructions/Lab%204%20pectoral2%20%20region.htm |title=LAB #4 PECTORAL REGION & Introduction to the Axilla |access-date=2007-12-23 }}</ref>  and by the [[rib]]cage
|| ''anteriorly'': by the [[pectoralis major muscle|pectoralis major]], [[pectoralis minor muscle|minor]],<ref name="titleDissector Answers - Axilla and Arm">{{cite web|url=http://anatomy.med.umich.edu/limbs/axilla_ans.html#2o |title=Dissector Answers - Axilla and Arm |access-date=2007-12-23 |archive-url=https://web.archive.org/web/20071210033208/http://anatomy.med.umich.edu/limbs/axilla_ans.html |archive-date=2007-12-10 |url-status=dead }}</ref> and [[subclavius muscle|subclavius]]<ref name="titleLAB #4 PECTORAL REGION & Introduction to the Axilla"/>

''posteriorly'': by the [[subscapularis muscle|subscapularis]] above, and [[teres major]] and [[latissimus dorsi]] below<ref name="titleLAB #4 PECTORAL REGION & Introduction to the Axilla"/> 
|| ''laterally'': by the [[humerus]] and the surrounding muscles of the arm [[coracobrachialis muscle|(coracobrachialis]] and [[biceps brachii muscle|biceps brachii]])<ref>{{Cite book|last1=Stingl|first1=Josef|title=Regional Anatomy|last2=Grim|first2=Miloš|last3=Druga|first3=Rastislav|publisher=Galén|year=2012|isbn=978-80-7262-931-2|location=Prague|pages=95|display-authors=1}}</ref>
|-
|  || ''floor/base'': by the skin<ref name="titleAnaesthesia UK :AnaesthesiaUK: Applied anatomy for upper limb blocks"/> (visible surface of axilla) ||
|}
The lower posterior boundary is called the '''posterior axillary fold''' and this is a compound structure consisting of the [[latissimus dorsi]] and [[teres major]] muscles.<ref name="NormanAnatomy|lesson3axilla">{{NormanAnatomy|lesson3axilla}}</ref> It can descend after weight loss.<ref name=pmid17602378>{{cite journal |doi=10.1055/s-2007-965236 |pmid=17602378 |title=Body Contouring of the Arms and Brachioplasty |journal=Handchirurgie · Mikrochirurgie · Plastische Chirurgie |volume=39 |issue=3 |pages=168–72 |year=2007 |last1=Hurwitz |first1=D. |last2=Neavin |first2=T. }}</ref>

The anterior boundary is called the '''anterior axillary fold''' and this is rounded in shape and formed by the lower border of the [[pectoralis major]]. 
Some sources also include the [[pectoralis minor]].<ref name="NormanAnatomy|lesson3axilla"/> It can elongate after weight loss.<ref name=pmid17602378/>

The contents of the axilla include the [[axillary vein]] and [[Axillary artery|artery]], as well as the [[brachial plexus]], [[lymph nodes]] and fat.
The axilla is the space between the side of the [[thorax]] and the upper arm.