Plantar Muscles of the Foot: Layer 1

00:01 Now let's go step by step through each of these layers.

00:05 So layer 1.

00:07 So here we can see a number of those muscles we mentioned previously.

00:10 These form the first layer on the sole of the foot, we have abductor digiti minimi, we have flexor digitorum brevis, and we have abductor hallucis.

00:22 Let's look at abductor digiti minimi.

00:25 It originates from the calcaneus and the plantar aponeurosis, on this medial aspect and then it passes towards the base of the proximal phalanx, of the fifth digit.

00:36 Is involved in abducting the little toe, or the fifth digit.

00:42 Here's flexor digitorum brevis.

00:44 Flexor digitorum brevis originates from the calcaneal tuberosity, also the plantar aponeurosis.

00:52 It then extends distally towards the sides on the plantar surface of the middle phalanges of the lateral four toes.

01:01 So they extend to the sides of the plantar surfaces of the middle phalanges of those lateral four toes.

01:08 So digits 2-5, not on the great toe.

01:12 This muscle flexor digitorum brevis is associated flexion of the lateral four toes.

01:19 So two toes 2-5.

01:21 Remember it missed out the great toe.

01:25 Now let's talk about abductor hallucis.

01:28 Abductor hallucis originates on this medial aspect.

01:32 It's coming from the calcaneal tuberosity and also the plantar aponeurosis and it extends distally towards the great toe, the proximal phalanx of the first digit.

01:44 This muscle abductor hallucis is associated with both flexion of the great toe and abduction of the great toe as well.

01:52 So two functions there of abductor hallucis.

01:57 The nerve supply to the first layer is via the lateral plantar nerve, which supplies abductor digiti minimi.

02:05 And then the medial plantar nerve, which is supplying both abductor hallucis and flexor digitorum brevis.