Flexor digitorum brevis muscle
Encyclopedia
The flexor digitorum brevis lies in the middle of the sole of the foot, immediately above the central part of the plantar aponeurosis
, with which it is firmly united.
Its deep surface is separated from the lateral plantar
vessels and nerves by a thin layer of fascia
.
It passes forward, and divides into four tendons, one for each of the four lesser toes.
Opposite the bases of the first phalanges, each tendon divides into two slips, to allow of the passage of the corresponding tendon of the flexor digitorum longus; the two portions of the tendon then unite and form a grooved channel for the reception of the accompanying long Flexor tendon.
Finally, it divides a second time, and is inserted into the sides of the second phalanx about its middle. The mode of division of the tendons of the flexor digitorum brevis, and of their insertion into the phalanges, is analogous to that of the tendons of the flexor digitorum superficialis
in the hand.
.
Aponeurosis
Aponeuroses are layers of flat broad tendons. They have a shiny, whitish-silvery color, are histologically similar to tendons, and are very sparingly supplied with blood vessels and nerves. When dissected, aponeuroses are papery, and peel off by sections...
, with which it is firmly united.
Its deep surface is separated from the lateral plantar
Sole
Sole may refer to:* Sole , the bottom of the foot* Sole , the bottom supporting member of the shoe-Business:* Sole proprietorship, a business which legally has no separate existence from its owner...
vessels and nerves by a thin layer of fascia
Fascia
A fascia is a layer of fibrous tissue that permeates the human body. A fascia is a connective tissue that surrounds muscles, groups of muscles, blood vessels, and nerves, binding those structures together in much the same manner as plastic wrap can be used to hold the contents of sandwiches...
.
Origin and insertion
It arises by a narrow tendon, from the medial process of the tuberosity of the calcaneus, from the central part of the plantar aponeurosis, and from the intermuscular septa between it and the adjacent muscles.It passes forward, and divides into four tendons, one for each of the four lesser toes.
Opposite the bases of the first phalanges, each tendon divides into two slips, to allow of the passage of the corresponding tendon of the flexor digitorum longus; the two portions of the tendon then unite and form a grooved channel for the reception of the accompanying long Flexor tendon.
Finally, it divides a second time, and is inserted into the sides of the second phalanx about its middle. The mode of division of the tendons of the flexor digitorum brevis, and of their insertion into the phalanges, is analogous to that of the tendons of the flexor digitorum superficialis
Flexor digitorum superficialis muscle
Flexor digitorum superficialis is an extrinsic flexor muscle of the fingers at the proximal interphalangeal joints....
in the hand.
Variations
Slip to the little toe may occasionally be absent, where it may be replaced by a small fusiform muscle arising from the long flexor tendon or from the quadratus plantæQuadratus plantae muscle
The Quadratus plantæ is separated from the muscles of the first layer by the lateral plantar vessels and nerve. It acts to aid in flexing the 2nd to 5th toes and is one of the few muscles in the foot with no homolog in the hand.It arises by two heads, which are separated from each other by the long...
.