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29.06.2013.

Muscles extending the toes





Extensor digitorum brevis
The lumbricals
The interossei

Extensor digitorum brevis

Extensor digitorum brevis is situated on the dorsum of the foot beyond the inferior part of the extensor retinaculum, lateral to and partly covered by the tendons of peroneus tertius and extensor digitorum longus. It is a thin muscle arising from the anterior roughened part of the upper surface of the calcaneus and the deep fascia covering the muscle, including the stem of the inferior extensor retinaculum. From the small belly, short tendons pass forwards and medially, the most medial of which crosses the dorsalis pedis artery to insert separately on to the dorsal aspect of the base of the proximal phalanx of the great toe. The remaining three tendons join the lateral side of the dorsal hood of the second, third and fourth toes. The most medial part of the muscle may develop a separate belly, sometimes reffered to as extensor hallucis brevis.

Nerve supply

This muscle is supplied by the deep peroneal nerve, root value L5, S1. The skin covering the muscle is supplied by roots L5, S1.

Action

The medial part of the muscle aids extensor hallucis longus in extending the great toe at the metatarsophalangeal joint, while the other three tendons aid extensor digitorum longus. As with the long extensor tendons, extensor digitorum brevis helps the lumbricals to extend the interphalangeal joints; however, it is unable to do this independently.

Functional activity

Extensor digitorum brevis will help extensor digitorum longus and extensor hallucis longus to raise the toes clear to the ground in running and walking.

Palpation

Place the fingers on the tendon of extensor digitorum longus as it splits into its four parts. When the toes are extended, extensor digitorum brevis can be felt just lateral and deep to the tendon. The tendons are difficult to trace distally as they become inseparable from those of extensor digitorum longus.

The lumbricals

These are four small muscles associated with the tendons of flexor digitorum longus; they pass from the flexor to the extensor compartment of the foot. The most medial of these muscles arises from the medial side of the tendon to the second toe, adjacent to the attachment of flexor accessories (quadratus plantae) to the main longus tendon. The remaining lumbricals arise by two heads from adjacent sides of two tendons, that is the second from the tendons to the second and third toes, the third from the tendons to the third and fourth toes, and the fourth from the tendons to the fourth and fifth toes. Each muscle then passes forwards below the deep transverse metatarsal ligament on the medial side of the toe, winding obliquely upwards to attach to the medial side of the extensor hood and base of the proximal phalanx.

Nerve supply

The first and most medial lumbrical is supplied by the medial plantar nerve, root value S1, 2, while the lateral three are supplied by the lateral plantar nerve, root value S2, 3; both being terminal branches of the tibial nerve. The skin on the dorsum of the foot at the point of attachment is supplied by roots L5, S1. The skin of the plantar aspect of the foot overlying the muscles is supplied by the medial and lateral plantar nerves, which have the same root values as the supply to the muscles. It should be noted, however, that only the most lateral of the lumbricals has skin over its plantar aspect.




Action

There has been much discussion about the role of these small, almost insignificant muscles. They have a long muscle belly compared with their tendon and they link the flexors of the toes with the extensors. By their attachment to the proximal phalanx, contraction of the lumbricals produces flexion of the toes at the metatarsophalangeal joint. However, because they also insert into the extensor hood, the lumbricals extend the interphalangeal joints. Indeed, this latter action is primarily due to the lumbricals and not the long and short extensor tendons.

Functional activity

The action of the lumbricals prevents clawing of the toes in the propulsive phase of gait. Paralysis of these muscles results in the extensor muscles pulling the toes into hyperextension at the metatarsophalangeal joint. Even at rest the toes become clawed.
The nerves which supply these muscles appear to have many more fibres than would be necessary for such a small muscle and a great number of these are sensory. This leads one to believe that they may have a very important function in providing information related to the tension developed between the long flexor and extensor muscles. This sort of information is of great importance in locomotion, especially as the point of attachment of the lumbricals is a long way from the muscle bellies of the extensors and flexors.

Palpation

It is not possible to palpate these muscles as they lie deep in the sole of the foot covered by many of the small muscles of the sole and the long flexor tendons.

Dorsal interossei

There are four dorsal interossei, being small bipennate muscles situated between the metatarsals. Each arises from the proximal half of the sides of adjacent metatarsals, forming a central tendon which passes forwards, deep to the deep transverse metatarsal ligament. It passes between the metatarsal heads to attach to the side of the proximal phalanx and capsule of the metatarsophalangeal joint. The tendons do not attach to the extensor hood.
The first, or most medial, arises from the adjacent sides of the first and second metatarsals and attaches to the medial side of the base of the proximal phalanx of the second toe. The second arises from the adjacent sides of the second and third metatarsals and it also attaches to the proximal phalanx of the second toe but to the lateral side. The third and fourth  dorsal interossei attach to the lateral side of the proximal phalanx of the third and fourth toes respectively.

Nerve supply

All four dorsal interossei are supplied by the lateral plantar nerve, root value S2, 3, those in the fourth interosseus space from the superficial branch, and the rest by the deep branch. The skin covering this area on the dorsum of the foot is supplied by root L5 medially and S1 laterally.

Action

The dorsal interossei abduct the toes at the metatarsophalangeal joint, however this action, as such, is of little importance in the foot. Acting with the plantar interossei, they will produce flexion of the metatarsophalangeal joint.

Functional activity

The dorsal interossei are powerful little muscles and their activity in combination with the plantar interossei controls the direction of the toes during violent activity, thus enabling the long and short flexors to perform their appropriate actions.
These muscles, because of their relationship to the metatarsophalangeal joint, can flex these joints and so raise the heads of the second, third and fourth metatarsals, thus helping to maintain the anterior metatarsal arch. They also help, to a limited extent, with the maintenance of the medial and lateral longitudinal arches of the foot.

Palpation

Place the finger tips between the proximal parts of the metatarsals on the dorsum of the foot; when the toes are abducted; the muscles can be felt to contract.



Plantar interossei

The plantar interossei are smaller than their dorsal counterparts, fusiform in shape and found in the lateral three interosseus spaces. Each arises from the plantar and medial aspect of the base and proximal end of the shaft of the metatarsal. The tendon formed passes forwards and deep to the deep transverse metatarsal ligament to insert into the medial side of the base of the proximal phalanx of the same toe.

Nerve supply

All the interossei are supplied by the lateral plantar nerve, root value S2, 3, with that in the fourth interosseus space being supplied by the superficial branch of the nerve. The skin covering the area is supplied on the lateral side by root S1 and medially by root L5.

Action

The plantar interossei adduct the third, fourth and fifth toes towards the second. In conjunction with the dorsal interossei they flex the metatarsophalangeal joints of the lateral three toes.

Functional activity

With the help of the dorsal interossei and abductor digiti minimi, the plantar interossei help to control the position of the third, fourth and fifth toes during the push-off phase of walking and running. They also help to prevent splaying of the toes when weight is suddenly applied to the forefoot.

Palpation

These muscles are too deep to be palpated. 

23.06.2013.

Stefan Mitrovic is the new member of Benfica!!!





“My legs were shakin’ once i stepped on “La Luge” in Lisabon, and my hands were shaking that much, that I barely signed a contract with the famous Portugalian Rui Costa. I am currently living my dream”, says Stefan Mitrovic(23) in one breath, seventh Serb, that will play this year in the kit of Benfica.

“Alo! Sprint” practically packed Stefan, with his wife Kristina, on the road to Lisabon, where they will, with Matic brothers, Nemanja and Uros, Markovic – Lazar and Phillip, and also with Phillip Djuricic and Miralem Sulejmani; try to remove “the curse” of “eagles” from Lisabon, one of the team with the greatest tradition in the world, and to bring them the title of the Portugal champ, and maybe bring them one of the European trophies.

<<<Once we are at Benfica’s curse, do you believe in that there is some higher force that doesn’t let them thrill in the end?
- It is all a little bit strange, but me, like the most of Serbs, don’t believe in these witchcrafts. Maybe that is the reason why they gathered the seven of us, to remove these witchcrafts – laughed Mitrovic, that was visited by us on Zvezdara.

<<<Are you in contact with some of teammates in Benfica?
 - Phillip Djuricic and I have the same manager, Oliver Kabrera.He connected us right away and we saw each other. I also know Lazar Markovic, we played one against other  in Jelen Superliga. I feel myself a lot easier when I go to the club that already has my teammates.

<<<How did you react, when you heard the info that you will go to Benfica, and to whom did you tell the great news first?
- Only one year ago, when I was fighting to stay in Jelen Superliga, i couldn’t even imagine that I will with 23 years play for the team from Lisabon. You won’t believe, but with the captain of Kortrijk, Nebojsa Pavlovic, only few days before the deal with Portugals, I spoke that I would like to play one day in some club like Liverpool, Athletic Bilbao or Benfica, but “eagles” are my most popular. And so as happened. That is why I told first to Nebojsa, and to the team scout of Kortrijk, Ivica Jerakovic. They couldn’t believe too. Just as I, even today, believe me, I am not aware of everything, though whole job was finished even in april.

<<<Who found out first from your family?
- Father Ljubisa, brother Aleksa, godfather and conditioning coach – Nenad Planic, and wife’s parents Gaga and Voja. It was a shock for them too, but they were very happy because of me.

<<<Feeling sorry for Red Star Belgrade!
<<<Whose fan are you in Serbian soccer?
 - I am a huge “delija”. As a kid I passed youth cathegories of Red Star and only few days before that youth cathegory should sign professional contract, director of youth school was changed. Except of Mitar Mrkela, Zlatko Krmpotic came and released us all as non-talented. Road led me then to Rad, then Artmedia, Brno, Kortrijk and now to Benfica. I feel sorry cause I never wore a kit of Red Star, but who knows. Maybe this will came true – said Stefan and added that, of course, he hopes for the call of Serbian national team.

03.06.2013.

Muscles everting the foot



Peroneus brevis

Peroneus brevis

Peroneus brevis is also situated on the lateral side of the leg enclosed in the same osteofascial compartment. It arises from the lower two-thirds of the lateral surface of the fibula, the upper half being anterior to peroneus longus. It also attaches to the intermuscular septa at all sides.
The muscle belly is fusiform and short, soon passing into a tendon which accompanies that of peroneus longus to pass behind the lateral malleolus in a common synovial sheath. The tendon then passes forwards and downwards into a groove above the peroneal tubercle of the calcaneus, which is converted into a tunnel by the inferior part of the peroneal retinaculum. It then passes forward to its insertion into the tubercle on the lateral side of the base of the fifth metatarsal. Above the tubercle, the tendon is surrounded by a synovial sheath, which is separated from that of peroneus longus. A slip from the tendon usually joins the long extensor to the little toe. Other separate slips may join peroneus longus, or pass to the calcaneus or cuboid.

Nerve supply

Peroneus brevis is supplied by the superficial peroneal nerve, root value L5, S1. The skin covering the muscle is innervated by L5, S1, 2.

Action

Peroneus brevis is an evertor of the foot. Because of its course and attachments, the pull of its tendon is in such a direction to produce plantarflexion of the ankle at the same time. 



Functional activity

This muscle is also well-positioned to prevent sideways sway in the standing position. In standing on one leg, it will help to prevent the body falling to the opposite side, thus working with a reversed origin and insertion. In walking or running, especially over the rough ground, it plays an important role in controlling the position of the foot and should prevent the foot from becoming too inverted. In many cases, however, this mechanism does not always appear to work correctly, and the foot over-inverts causing the weight to come down on the lateral side of the foot forcing the foot into further inversion. This can severely damage or even snap the tendon of the muscle and often the anterior talofibular ligament of the ankle joint.

Palpation

If the fingers are placed on the belly of peroneus longus and then moved downwards to the lower half of the fibula (but in the same vertical line), the belly of peroneus brevis can be palpated when the foot is everted and plantarflexed. Its tendon can easily be traced to the groove just above the peroneal tubercle and then forwards to its insertion into the tubercle of the fifth metatarsal.


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