An extensor expansion (extensor hood,[1]dorsal expansion, dorsal hood, dorsal aponeurosis[citation needed]) is the special connective attachments by which the extensor tendons insert into the phalanges.
Extensor expansion
Extensor expansion covers the tendon of extensor digitorum tendons over the proximal phalanges
These flattened tendons (aponeurosis) of extensor muscles span the proximal and middle phalanges.[2]
At the distal end of the metacarpal, the extensor tendon will expand to form a hood, which covers the back and sides of the head of the metacarpal and the proximal phalanx.
A single median band passes down the middle of the finger along the back of the proximal phalanx, inserting into the base of the middle phalanx.
A band known as the retinacular ligament runs obliquely along the middle phalanx, and connects the fibrous digital sheath on the anterior side of the phalanges to the extensor expansion.
Functionedit
The extensor expansion allows for contractile forces from the extensor compartment muscles to be transferred to the phalanges. It also balances the forces across the phalanges.[1]
Referencesedit
^ abBlankenbaker, Donna G.; Davis, Kirkland W.; Sonin, Andrew; Crim, Julia R., eds. (2016-01-01), "Extensor Tendon Injury, Wrist and Fingers", Diagnostic Imaging: Musculoskeletal Trauma (Second Edition), Diagnostic Imaging, Elsevier, pp. 468–473, doi:10.1016/b978-0-323-39253-2.50118-x, ISBN978-0-323-39253-2, retrieved 2021-01-04
^"eMedicine - Hand, Tendon Lacerations: Extensors : Article by D Glynn Bolitho, MD, PhD, FACS". Retrieved 2008-01-20.[failed verification]
^Kyung Won, PhD. Chung (2005). Gross Anatomy (Board Review). Hagerstown, MD: Lippincott Williams & Wilkins. p. 43. ISBN0-7817-5309-0.
External linksedit
lesson5musofpostforearm at The Anatomy Lesson by Wesley Norman (Georgetown University)
Hand kinesiology at the University of Kansas Medical Center
extensor, expansion, extensor, expansion, extensor, hood, dorsal, expansion, dorsal, hood, dorsal, aponeurosis, citation, needed, special, connective, attachments, which, extensor, tendons, insert, into, phalanges, covers, tendon, extensor, digitorum, tendons,. An extensor expansion extensor hood 1 dorsal expansion dorsal hood dorsal aponeurosis citation needed is the special connective attachments by which the extensor tendons insert into the phalanges Extensor expansionExtensor expansion covers the tendon of extensor digitorum tendons over the proximal phalangesTA22502Anatomical terminology edit on Wikidata These flattened tendons aponeurosis of extensor muscles span the proximal and middle phalanges 2 At the distal end of the metacarpal the extensor tendon will expand to form a hood which covers the back and sides of the head of the metacarpal and the proximal phalanx Contents 1 Bands 2 Function 3 References 4 External linksBands editThe expansion soon divides into three bands lateral bands pass on either side of the proximal phalanx and stretch all the way to the distal phalanx The lumbricals of the hand extensor indicis muscle 3 dorsal interossei of the hand and palmar interossei insert on these bands A single median band passes down the middle of the finger along the back of the proximal phalanx inserting into the base of the middle phalanx A band known as the retinacular ligament runs obliquely along the middle phalanx and connects the fibrous digital sheath on the anterior side of the phalanges to the extensor expansion Function editThe extensor expansion allows for contractile forces from the extensor compartment muscles to be transferred to the phalanges It also balances the forces across the phalanges 1 References edit a b Blankenbaker Donna G Davis Kirkland W Sonin Andrew Crim Julia R eds 2016 01 01 Extensor Tendon Injury Wrist and Fingers Diagnostic Imaging Musculoskeletal Trauma Second Edition Diagnostic Imaging Elsevier pp 468 473 doi 10 1016 b978 0 323 39253 2 50118 x ISBN 978 0 323 39253 2 retrieved 2021 01 04 eMedicine Hand Tendon Lacerations Extensors Article by D Glynn Bolitho MD PhD FACS Retrieved 2008 01 20 failed verification Kyung Won PhD Chung 2005 Gross Anatomy Board Review Hagerstown MD Lippincott Williams amp Wilkins p 43 ISBN 0 7817 5309 0 External links editlesson5musofpostforearm at The Anatomy Lesson by Wesley Norman Georgetown University Hand kinesiology at the University of Kansas Medical Center nbsp This human musculoskeletal system article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Extensor expansion amp oldid 998235925, wikipedia, wiki, book, books, library,
