Editing Forearm (section)

{{short description|Region of the upper limb between the elbow and the wrist}}
{{About|the body part|other uses}}
{{Infobox anatomy
| Name        = Forearm
| Latin       = antebrachium
| Image       = Forearm labeled.png
| Caption     = The forearm is highlighted in magenta
| Width       = 150px
| Caption2    =
| Precursor   =
| System      =
| Artery      =
| Vein        =
| Nerve       =
| Lymph       =
}}
The '''forearm''' is the region of the [[upper limb]] between the [[Elbow-joint|elbow]] and the [[wrist]].<ref>{{cite book |author=WebMD |chapter=forearm |chapter-url=https://books.google.com/books?id=t8UfI3BH78wC&pg=PA166 |page=166 |year=2009 |title=Webster's New World Medical Dictionary |edition=3rd |publisher=Houghton Mifflin Harcourt |isbn=978-0-544-18897-6}}</ref> The term forearm is used in [[anatomy]] to distinguish it from the [[arm]], a word which is used to describe the entire appendage of the upper limb, but which in anatomy, technically, means only the region of the upper arm, whereas the lower "arm" is called the forearm. It is [[Homology (biology)|homologous]] to the region of the [[Human leg|leg]] that lies between the [[knee]] and the [[ankle]] joints, the [[Human leg#Structure|crus]].

The forearm contains two long [[bone]]s, the [[Radius (bone)|radius]] and the [[ulna]],<ref>{{cite web|url=https://www.lecturio.com/concepts/forearm/|title=Forearm|website=The Lecturio Medical Concept Library|access-date=2021-06-22}}</ref> forming the two radioulnar joints. The [[Interosseous membrane of forearm|interosseous membrane]] connects these bones. Ultimately, the forearm is covered by skin, the anterior surface usually being less hairy than the posterior surface.

The forearm contains many muscles, including the flexors and extensors of the [[wrist]], flexors and extensors of the digits, a flexor of the elbow ([[brachioradialis]]), and [[pronator]]s and [[supinator]]s that turn the hand to face down or upwards, respectively. In cross-section, the forearm can be divided into two [[fascial compartment]]s. The posterior compartment contains the extensors of the hands, which are supplied by the [[radial nerve]]. The anterior compartment contains the flexors and is mainly supplied by the [[median nerve]]. The flexor muscles are more massive than the extensors because they work against gravity and act as anti-gravity muscles. The [[ulnar nerve]] also runs the length of the forearm.<ref>{{cite web |url=https://www.ncbi.nlm.nih.gov/books/NBK536975/ |title=Anatomy, Shoulder and Upper Limb, Forearm Muscles|last1=Mitchell  |first1=Brittney  |last2=Whited |first2=Lacey |publisher=StatPearls Publishing LLC. |date=2020-08-15 |website=National Center for Biotechnology Information, U.S. National Library of Medicine |access-date=22 June 2021}}</ref>

The [[Radial artery|radial]] and [[Ulnar artery|ulnar arteries]] and their branches supply the blood to the forearm. These usually run on the anterior face of the radius and ulna down the whole forearm. The main superficial veins of the forearm are the [[Cephalic vein|cephalic]], [[Median antebrachial vein|median antebrachial]] and the [[basilic vein]]. These veins can be used for cannularisation or [[venipuncture]], although the [[cubital fossa]] is a preferred site for getting blood.