Common plantar digital branches of medial plantar nerve

At a glance

English

Common plantar digital branches of medial plantar nerve

Latin (TA2)

Rami digitales plantares communes nervi plantaris medialis

System

Nerve

Region

Lower limb

Side

Single, on the midline

About the common plantar digital branches of medial plantar nerve

Opposite the bases of the metatarsal bones, the medial plantar nerve ends by dividing into three common plantar digital nerves, having already given off a separate proper digital nerve for the medial side of the great toe. Each common nerve runs forwards in the sole towards one of the first three interdigital clefts, passing between the slips into which the plantar aponeurosis divides near the toes.

Close to the webs each common nerve splits into two proper plantar digital nerves. The first common nerve serves the facing sides of toes one and two, the next one toes two and three, and the last one toes three and four. A motor twig to the first lumbrical also comes from the first. The third is joined by a communicating twig of the lateral plantar nerve, so the skin of the third web space and fourth toe often has a shared supply.

The proper digital nerves they form give cutaneous and articular filaments along the sides of the toes. Near the last phalanx each sends a small branch onto the dorsum to supply the nail bed and the skin around it, and the rest of the nerve ends in the ball of the toe. Together with the great toe's own branch, this gives the medial plantar nerve the plantar skin of the medial three and a half toes, a pattern closely like the median nerve's digital branches in the hand.

Each common nerve passes under the deep transverse metatarsal ligament with the digital vessels, and repeated squeezing there can thicken the nerve into a Morton's neuroma. This is most common in the third web space, where the third common nerve is joined by lateral plantar fibres, and less often in the second. It causes burning or shooting pain and numbness in the affected toes, often relieved by taking off narrow shoes. Treatment ranges from wider footwear and pads to steroid injection or removal of the thickened nerve segment.

Course and supply

Arises from

The medial plantar nerve, dividing opposite the bases of the metatarsals.

Ends in

Each ends near a toe web by dividing into two proper plantar digital nerves for the first to fourth toes.

Supplies

Sensory to the plantar skin and nail beds of the facing sides of the first to fourth toes; the first branch also supplies the first lumbrical.