Editing Anatomical snuffbox

{{Short description|Indent on back of hand between tendons}}
{{Infobox anatomy
| Name        = Anatomical snuffbox
| Latin       = fovea radialis
| Greek       = 
| Image       = Anatomical snuffbox IMG 6853 a.jpg
| Caption     = Anatomical snuffbox
| Width       = 
| Image2      = Gray424.png
| Caption2    = The mucous sheaths of the tendons on the back of the wrist. (Anatomical snuffbox not labeled, but visible at right.)
| Precursor   = 
| System      = 
| Artery      = [[Radial artery]]
| Vein        = [[Cephalic vein]]
| Nerve       = [[Radial nerve]]
| Lymph       = 
}}
The '''anatomical snuff box''' or '''snuffbox''' or '''foveola radialis''' is a triangular deepening on the [[Anatomical terms of location#Relative directions|radial]], [[Dorsum (biology)|dorsal]] aspect of the [[hand]]—at the level of the [[carpal bones]], specifically, the [[Scaphoid bone|scaphoid]] and [[Trapezium (bone)|trapezium]] bones forming the floor. The name originates from the use of this surface for placing and then sniffing powdered [[tobacco]], or "[[Snuff (tobacco)|snuff]]."<ref>{{Citation |last=Hallett |first=Sasha |title=Anatomy, Shoulder and Upper Limb, Hand Anatomical Snuff Box |date=2025 |work=StatPearls |url=https://www.ncbi.nlm.nih.gov/books/NBK482228/# |access-date=2025-01-10 |place=Treasure Island (FL) |publisher=StatPearls Publishing |pmid=29489241 |last2=Jozsa |first2=Felix |last3=Ashurst |first3=John V.}}</ref> It is sometimes referred to by its [[French language|French]] name ''tabatière''.

==Structure==
===Boundaries===
* The medial border (ulnar side) of the snuffbox is the [[tendon]] of the [[extensor pollicis longus]]
* The lateral border (radial side) is a pair of parallel and intimate tendons, of the [[extensor pollicis brevis]] and the [[abductor pollicis longus]].<ref name="titleChapter 10: THE FOREARM">{{cite web |url=http://www.dartmouth.edu/~humananatomy/part_2/chapter_10.html#chpt_10_muscles_back |title=Chapter 10: THE FOREARM |access-date=2008-01-05 | archive-url= https://web.archive.org/web/20071209190234/http://www.dartmouth.edu/~humananatomy/part_2/chapter_10.html| archive-date= 9 December 2007 | url-status= live}}</ref> (Accordingly, the anatomical snuffbox is most visible, having a more pronounced concavity, during thumb [[Extension (kinesiology)|extension]].)
* The [[Anatomical terms of location#Proximal and distal|proximal]] border is formed by the [[Radial styloid process|styloid process]] of the [[Radius (bone)|radius]]
* The [[Anatomical terms of location#Proximal and distal|distal]] border is formed by the approximate apex of the schematic snuffbox [[isosceles]] triangle.
* The floor of the snuffbox varies depending on the position of the wrist, but both the [[Trapezium (bone)|trapezium]] and primarily the [[scaphoid]] can be palpated.

=== Neurovascular anatomy ===
Deep to the tendons which form the borders of the anatomical snuff box lies the [[radial artery]], which passes through the anatomical snuffbox on its course from the normal radial pulse detecting area, to the proximal space in between the first and second [[metacarpals]] to contribute to the [[Superficial palmar arch|superficial]] and [[deep palmar arch]]es. In the anatomical snuffbox, the radial artery is closely related (<2&nbsp;mm) with the [[superficial branch of radial nerve]] near the styloid process of radius in 48%, while in 24% the radial artery is openly related to the [[lateral cutaneous nerve of forearm]].<ref>{{Cite journal|last=Robson|first=A. J.|last2=See|first2=M. S.|last3=Ellis|first3=H.|date=2008|title=Applied anatomy of the superficial branch of the radial nerve|journal=Clinical Anatomy|volume=21|issue=1|pages=38–45|doi=10.1002/ca.20576|issn=1098-2353|pmid=18092362}}</ref> The [[cephalic vein]] arises within the anatomical snuffbox, while the [[Superficial branch of radial nerve|dorsal cutaneous branch]] of the [[radial nerve]] can be palpated by stroking along the extensor pollicis longus with the dorsal aspect of a fingernail.

==Clinical significance==
The radius and scaphoid articulate deep to the snuffbox to form the basis of the wrist joint. In the event of a fall onto an outstretched hand (FOOSH), this is the area through which the brunt of the force will focus. This results in these two bones being the most often fractured of the wrist. In a case where there is localized [[Tenderness (medicine)|tenderness]] within the snuffbox, knowledge of wrist anatomy leads to the speedy conclusion that the fracture is likely to be of the [[Scaphoid bone|scaphoid]]. This is understandable as the scaphoid is a small, oddly shaped bone whose purpose is to facilitate mobility rather than confer stability to the wrist joint {{citation needed|date=July 2015}}. In the event of inordinate application of force over the wrist, this small scaphoid is likely to be the weak link {{citation needed|date=July 2015}}. [[Scaphoid fracture]] is one of the most frequent causes of medico-legal issues.

An anatomical anomaly in the vascular supply to the scaphoid is the area to which the blood supply is first delivered. Blood enters the scaphoid distally. Consequently, in the event of a fracture the proximal segment of the scaphoid will be devoid of a vascular supply, and will—if action is not taken—avascularly [[necrosis|necrose]] within a sufferer's snuffbox. Due to the small size of the scaphoid and its shape, it is difficult to determine, early on, whether or not the scaphoid is indeed fractured with an x-ray. Further complications include; carpal instability (ligament disruption) and fracture-dislocations.

==Additional images==
<gallery>
File:Gray416.png|Tendons of forefinger and vincula tendina.
File:Gray573.png|The veins on the dorsum of the hand.
File:Gray1237.svg|Palm of left hand, showing position of skin creases and bones, and surface markings for the volar arches.
File:Anatomical snuff box2.jpg|A particularly cavernous anatomical snuff box.
File:Schematic drawing of anatomical snuffbox.png|Schematic drawing of anatomical snuffbox.
</gallery>

==See also==
* [[Anatomical terminology]]
* [[Anatomical terms of bone]]
* [[Cephalic vein]]

==References==
{{Reflist}}

==External links==
{{Commons category|Anatomical snuff box}}
*[http://www.instantanatomy.net/arm/surface/snuffbox.html "Instant Anatomy"]

{{Superficial anatomy of limbs}}
{{Muscles_of_upper limb}}

{{DEFAULTSORT:Anatomical Snuff Box}}
[[Category:Hand]]
[[Category:Anatomy]]