Intrinsic muscles- fourth layer

Question 1

Dorsal Interossei

Answer 1

O- sides of adjacent metatarsals
I- free margin of the extensor hods and base of the proximal phalanges of the toe
A- abduction of the 2 to 4 toes at metatarsophalangeal joint
dorsal interossei act through extensor hoods to resist extension of the metatarsophalangeal joints and flexion of the interphalangeal joints
I- lateral plantar nerve from tibial nerve
1st and 2nd dorsal interossei also receives branches on their superior surface from the deep fibular nerve S2, S3

Question 2

Plantar interossei

Answer 2

O- medial side of metatarsals 3 to 5
I- medial free margin of the extensor hood and base of the proximal phalanx/ phalanges of toes 3 to 5
A- adduction of 3 to 5 toes at metatarsophalangeal joints
act through the extensor hoods to resist extension of the metatarsophalangeal joints and flexion of the interphalangeal joints
I- lateral plantar nerve from tibial nerve S2,S3