The flexor digitorum longus muscle is situated on the tibial side of the leg. At its origin it is thin and pointed, but it gradually increases in size as it descends. It serves to flex the second, third, fourth, and fifth toes.
The flexor digitorum longus runs along the medial posterior side of the lower leg and aids in flexions of the toes (apart from the big toe).
The flexor digitorum longus muscle arises from the posterior surface of the body of the tibia, from immediately below the soleal line to within 7 or 8 cm of its lower extremity, medial to the tibial origin of the tibialis posterior muscle. It also arises from the fascia covering the tibialis posterior muscle.
The fibers end in a tendon, which runs nearly the whole length of the posterior surface of the muscle. This tendon passes behind the medial malleolus, in a groove, common to it and the tibialis posterior, but separated from the latter by a fibrous septum, each tendon being contained in a special compartment lined by a separate mucous sheath. The tendon of the tibialis posterior and the tendon of the flexor digitorum longus cross each other, in a spot above the medial malleolus, the crural tendinous chiasm.[1][2][3] It passes through the tarsal tunnel.[4]
It passes obliquely forward and lateralward, superficial to the deltoid ligament of the ankle-joint, into the sole of the foot, where it crosses over the tendon of the flexor hallucis longus at the level of the navicular bone at a location known as the knot of henry[5] (also referred to as plantar tendinous chiasm),[1][2][3] and receives from it a strong tendinous slip.
It then expands and is joined by the quadratus plantæ muscle, and finally divides into four tendons, which are inserted into the bases of the last phalanges of the second, third, fourth, and fifth toes, each tendon passing through an opening in the corresponding tendon of the flexor digitorum brevis muscle opposite the base of the first interphalangeal joint.
VariationEdit
Flexor accessorius longus digitorum, not infrequent, origin from fibula, or tibia, or the deep fascia and ending in a tendon which, after passing beneath the laciniate ligament, joins the tendon of the long flexor or the quadratus plantæ.
FunctionEdit
Similar to the flexor hallucis longus and tibialis posterior muscles, the flexor digitorum longus muscle functions to plantar flex and invert the foot. The flexor digitorum longus muscle is responsible for the movement and curling of the second, third, fourth and fifth toes. This muscle makes it possible for the toes to grip the surface of floors, which is important when it comes to maintaining postural balance on surfaces that are rough or uneven. The other deep muscles are the flexor hallucis longus and tibialis posterior; the tibialis posterior is the most powerful of these deep muscles. All three muscles are innervated by the tibial nerve which comprises half of the sciatic nerve.
Clinical significanceEdit
After passing through the tarsal tunnel, the flexor digitorum longus tendon must curve around a bony landmark called the sustentaculum tali. Flexor digitorum longus pain can occur with a trip and fall on uneven surface when the toes are not able to grip the surface totally. One can also injure the flexor digitorum longus muscle while running on a beach in the sand without any footwear, making the muscle vulnerable at the calcaneus attachment for injuries. In case of flexor digitorum longus pain or strain, the patient will find it tough to walk and will have excruciating pain in the feet and ankles. Support braces along with warm compresses are the most preferred way of treating flexor digitorum longus pain or strain.
ReferencesEdit
This article incorporates text in the public domain from page 485 of the 20th edition ofGray's Anatomy(1918)
^ abWalter Thiel (1997) Photographic atlas of practical anatomy - Volume 1, Part 1 - p.348
^ abJohannes Sobotta, Reinhard Putz, Reinhard Pabst (1997) Sobotta Atlas of Human Anatomy: Thorax, abdomen, pelvis, lower limb, p.331
^ abJan Langman, Martinus Willem Woerdeman (1982) Atlas of medical anatomy p.323
^Gujar, Bansari; Flores, Raymond H. (2015-01-01), Hochberg, Marc C.; Silman, Alan J.; Smolen, Josef S.; Weinblatt, Michael E. (eds.), "81 - Entrapment neuropathies and compartment syndromes", Rheumatology (Sixth Edition), Philadelphia: Mosby, pp. 671–682, doi:10.1016/b978-0-323-09138-1.00081-4, ISBN978-0-323-09138-1
^Knipe, Henry. "Knot of Henry | Radiology Reference Article | Radiopaedia.org". Radiopaedia. Retrieved 20 October 2020.
External linksEdit
Wikimedia Commons has media related to Flexor digitorum longus muscles.
Anatomy photo:15:st-0403 at the SUNY Downstate Medical Center
flexor, digitorum, longus, muscle, flexor, digitorum, longus, muscle, situated, tibial, side, origin, thin, pointed, gradually, increases, size, descends, serves, flex, second, third, fourth, fifth, toes, view, from, belowdetailsoriginposterior, surface, body,. The flexor digitorum longus muscle is situated on the tibial side of the leg At its origin it is thin and pointed but it gradually increases in size as it descends It serves to flex the second third fourth and fifth toes Flexor digitorum longus muscleView from belowDetailsOriginPosterior surface of the body of the tibiaInsertionPlantar surface base of the distal phalanges of the four lesser toesArteryposterior tibial arteryNerveTibial nerveActionsFlexion of the four smaller digitsAntagonistExtensor digitorum longus Extensor digitorum brevisIdentifiersLatinMusculus flexor digitorum longusTA98A04 7 02 052TA22667FMA51071Anatomical terms of muscle edit on Wikidata Contents 1 Structure 1 1 Variation 2 Function 3 Clinical significance 4 References 5 External linksStructure Edit The flexor digitorum longus runs along the medial posterior side of the lower leg and aids in flexions of the toes apart from the big toe The flexor digitorum longus muscle arises from the posterior surface of the body of the tibia from immediately below the soleal line to within 7 or 8 cm of its lower extremity medial to the tibial origin of the tibialis posterior muscle It also arises from the fascia covering the tibialis posterior muscle The fibers end in a tendon which runs nearly the whole length of the posterior surface of the muscle This tendon passes behind the medial malleolus in a groove common to it and the tibialis posterior but separated from the latter by a fibrous septum each tendon being contained in a special compartment lined by a separate mucous sheath The tendon of the tibialis posterior and the tendon of the flexor digitorum longus cross each other in a spot above the medial malleolus the crural tendinous chiasm 1 2 3 It passes through the tarsal tunnel 4 It passes obliquely forward and lateralward superficial to the deltoid ligament of the ankle joint into the sole of the foot where it crosses over the tendon of the flexor hallucis longus at the level of the navicular bone at a location known as the knot of henry 5 also referred to as plantar tendinous chiasm 1 2 3 and receives from it a strong tendinous slip It then expands and is joined by the quadratus plantae muscle and finally divides into four tendons which are inserted into the bases of the last phalanges of the second third fourth and fifth toes each tendon passing through an opening in the corresponding tendon of the flexor digitorum brevis muscle opposite the base of the first interphalangeal joint Variation Edit Flexor accessorius longus digitorum not infrequent origin from fibula or tibia or the deep fascia and ending in a tendon which after passing beneath the laciniate ligament joins the tendon of the long flexor or the quadratus plantae Function EditSimilar to the flexor hallucis longus and tibialis posterior muscles the flexor digitorum longus muscle functions to plantar flex and invert the foot The flexor digitorum longus muscle is responsible for the movement and curling of the second third fourth and fifth toes This muscle makes it possible for the toes to grip the surface of floors which is important when it comes to maintaining postural balance on surfaces that are rough or uneven The other deep muscles are the flexor hallucis longus and tibialis posterior the tibialis posterior is the most powerful of these deep muscles All three muscles are innervated by the tibial nerve which comprises half of the sciatic nerve Clinical significance EditAfter passing through the tarsal tunnel the flexor digitorum longus tendon must curve around a bony landmark called the sustentaculum tali Flexor digitorum longus pain can occur with a trip and fall on uneven surface when the toes are not able to grip the surface totally One can also injure the flexor digitorum longus muscle while running on a beach in the sand without any footwear making the muscle vulnerable at the calcaneus attachment for injuries In case of flexor digitorum longus pain or strain the patient will find it tough to walk and will have excruciating pain in the feet and ankles Support braces along with warm compresses are the most preferred way of treating flexor digitorum longus pain or strain References Edit This article incorporates text in the public domain from page 485 of the 20th edition of Gray s Anatomy 1918 a b Walter Thiel 1997 Photographic atlas of practical anatomy Volume 1 Part 1 p 348 a b Johannes Sobotta Reinhard Putz Reinhard Pabst 1997 Sobotta Atlas of Human Anatomy Thorax abdomen pelvis lower limb p 331 a b Jan Langman Martinus Willem Woerdeman 1982 Atlas of medical anatomy p 323 Gujar Bansari Flores Raymond H 2015 01 01 Hochberg Marc C Silman Alan J Smolen Josef S Weinblatt Michael E eds 81 Entrapment neuropathies and compartment syndromes Rheumatology Sixth Edition Philadelphia Mosby pp 671 682 doi 10 1016 b978 0 323 09138 1 00081 4 ISBN 978 0 323 09138 1 Knipe Henry Knot of Henry Radiology Reference Article Radiopaedia org Radiopaedia Retrieved 20 October 2020 External links Edit Wikimedia Commons has media related to Flexor digitorum longus muscles Anatomy photo 15 st 0403 at the SUNY Downstate Medical Center PTCentral Portal Anatomy Retrieved from https en wikipedia org w index php title Flexor digitorum longus muscle amp oldid 1139551654, wikipedia, wiki, book, books, library,
