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==Background==
[[File:Gray817.png|thumb|Deep palmar nerves]]
*Each digit is innervated by 4 nerves
**2 Dorsal (10 and 2 o'clock positions)
**2 Ventral - palmar or plantar (4 and 8 o'clock positions)

==Indications==
*Need to anesthetize entire digit (finger or toe)
**[[Laceration repair]]
**[[joint dislocations|Dislocation]]/[[fracture]] reduction
**[[analgesia|Pain control]] for traumatic injury
**[[Paronychia]]
**[[Felon]]
**[[Nail trephination]] or removal

==Contraindications==
*Overlying skin infection
*Distortion of landmarks

==Equipment Needed==
*PPE
*Local anesthetic
*27-30ga needle
*5-10 mL Syringe
*Iodine or chlorhexadine prep

{{Maximum doses of anesthetic agents}}

===[[Epinephrine]] in Digital Block===
*Previously, "conventional wisdom" argued that it is unsafe to use epinephrine in digital local anesthesia.
*However, many studies going back more than a decade have shown that using local anesthetic with epinephrine is safe for use in digits.<ref>Denkler K. A comprehensive review of epinephrine in the finger: to do or not to do. Plast Reconstr Surg. 2001 Jul;108(1):114-24.</ref><ref>Krunic AL, Wang LC, Soltani K, Weitzul S, Taylor RS. Digital anesthesia with epinephrine: an old myth revisited. J Am Acad Dermatol. 2004 Nov;51(5):755-9.</ref><ref>Chowdhry S, Seidenstricker L, Cooney DS, Hazani R, Wilhelmi BJ. Do not use epinephrine in digital blocks: myth or truth? Part II. A retrospective review of 1111 cases. Plast Reconstr Surg. 2010 Dec;126(6):2031-4</ref>
*A Cochrane Review concurs that no adverse effects have been reported, but notes that the level of evidence is poor and further high quality studies are required.<ref>Prabhakar H, Rath S, Kalaivani M, Bhanderi N. Adrenaline with lidocaine for digital nerve blocks. Cochrane Database Syst Rev. 2015 Mar 19;3</ref>

==Procedure==
===Traditional Technique<ref name="Block1">Harness NG. Digital block anesthesia. J Hand Surg Am. 2009 Jan;34(1):142-5.</ref><ref name="AEM">Hill RG Jr, Patterson JW, Parker JC, et al. Comparison of transthecal digital block and traditional digital block for anesthesia of the finger. Ann Emerg Med. 1995 May;25(5):604-7.</ref>===
[[File:Digital nerves.png|thumb|Cross sectional anatomy of digit with four nerves (dark circles) shown. Note that palmar nerves are more medial than dorsal nerves. Arrow shows needle trajectory of traditional technique.]]
*Cleanse skin at proximal, dorsal aspect of the digit to be anesthetized, including web space
*Introduce the needle at the base of the digit near the MCP joint, lateral to the midline of the digit.
*Advance the needle around the bone towards the ventral side of the digit - stop if skin tenting is noted
*Inject ~1mL of anesthetic to block ventral digital nerve
*As needle is withdrawn, inject additional ~1mL of anesthetic to block dorsal digital nerve
*Repeat on opposite side of digit

===Transthecal Technique<ref name="TTB">Hart RG, Fernandas FA, Kutz JE. Transthecal digital block: an underutilized technique in the ED. Am J Emerg Med. 2005 May;23(3):340-2.</ref>===
'''Described for finger blocks - most effective in 2nd-5th digits'''<br>
'''Contraindicated if flexor tendon involvement or infection (e.g. felon, tenosynovitis, etc)''' 
*With hand supinated, locate flexor tendon of finger to be anesthetized
*Cleanse skin over the distal palmar crease and proximal digital crease

*Method 1
**Insert needle 90 degrees to the skin at the proximal digital crease
**Advance until needle hits bone, then withdraw 2-3mm
**Redirect needle 45 degrees to the skin with needle pointing distally (towards finger tip)
**Slowly inject anesthetic - initially no resistance, progressive resistance felt as tendon sheath fills (~1.5-3mL)
*Method 2
**Insert needle at 45 degrees to the skin just distal to the distal palmar crease
**Advance into flexor tendon sheath
**Slowly inject anesthesic - if resistance to injection felt, withdraw needle slightly

==Complications==
*Damage to surrounding structures
*Bleeding
*Infection
*Accidental intravascular injection of anesthetic

==See Also==
*[[Nerve Blocks (Main)]]

==External Links==

===Videos===
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==References==
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[[Category:Procedures]]