Adductor
hallucis
Adductor
hallucis is situated deep within the plantar aspect of the foot. It arises by two heads, oblique and transverse. The
oblique head comes from the plantar surface of the based of the second, third
and fourth metatarsals and the sheath of the tendon of peroneus longus. The transverse head comes from the plantar surface
of the lateral three metatarsophalangeal joints and the deep transverse
metatarsal ligament.
The
muscle fibers of the oblique head pass forwards and medially while those of the
transverse head pass medially. The two heads unite and blend with the medial
part of the flexor hallucis brevis to
insert into the lateral side of the base of the proximal phalanx of the great
toe.
Nerve supply
Adductor
hallucis is supplied by the lateral
plantar nerve, root value S2, 3, and the skin covering this area is supplied
by root S1.
Action
It
will adduct the great toe towards the second toe, and flex the first
metatarsophalangeal joint.
Functional activity
Working
with abductor hallucis, adductor
hallucis helps to control the position of the great toe so that active flexion
can be produced and thereby provide the final thrust needed in walking, running
or jumping. Due to its transverse position across the forefoot it will also
help to maintain the anterior metatarsal arch of the foot.
The
pull of adductor hallucis is almost at right angles to the phalanx and
therefore will have a better mechanical advantage than abductor hallucis. If the medial longitudinal arch is allowed to
fall, allowing the foot to drift
medially and the toes laterally, the pull of adductor hallucis will overcome
that of the abductor, thus adding to the deformity often seen in the great toe.
Palpation
This
muscle is too deep to be palpated.
0 коментара:
Постави коментар