Plantar Nerves

Plantar Nerves are the nerves that go through the ankle joint to the sole of the foot. Plantar refers to anything that is related to the sole of the foot. There are 2 plantar nerves- medial and lateral.

Medial Plantar Nerve

The medial plantar nerve is the pre-axial nerve of the foot.

Origin And Course

It’s the bigger terminal branch of the tibial nerve and starts deep to flexor retinaculum. It enters forward between the abductor hallucis and flexor digitorum brevis. It’s escorted by the medial plantar artery on its medial side.

Branches And Distribution

It give rise to these branches:

• Muscular branches to 4 muscles:
  1. Abductor halluces.
  2. Flexor digitorum brevis.
  3. Flexor hallucis brevis, by first digital nerve to the medial side of the big toe.
  4. First lumbrical, by the next digital nerve.
• Cutaneous branches (4 digital nerves) supplies skin of the medial 3.5 toes and bigger medial part of the sole. Every digital nerve also supplies dorsum of the terminal phalanx.
• Articular branches supplies the joints of tarsus and metatarsus.

The distribution of medial plantar nerve in the sole corresponds to the distribution of median nerve in the hand.

Clinical Significance

Medial plantar nerve entrapment: The medial plantar nerve might be compressed either deep to flexor retinaculum or deep to abductor hallucis as a result of persistent eversion of the foot (example, during gymnastics and running). Medically, it presents as burning, numbness, and tingling (paraesthesia) on the medial side of the sole and in the region of navicular tuberosity.

Since it typically takes place in runners, this illness is called “jogger’s foot”.

Lateral Plantar Nerve

The lateral plantar nerve is the post-axial nerve of the foot.

Origin and Course

It’s the smaller terminal branch of the tibial nerve and starts deep to the flexor retinaculum. It seems in the sole deep to the abductor hallucis. It enters forward and laterally to the base of the fifth metatarsal between the first and 2nd layers of the muscles. On reaching between flexor digitorum brevis and abductor digiti minimi, it breaks up into the superficial and deep branches.

Branches and Distribution

It give rise to these branches:

• Branches from the principal trunk:
  1. Cutaneous to lateral part of the lone.
  2. Muscular to provide 2 muscles: abductor digiti minimi and flexor digitorum accessorius.
• Branches from the superficial branch: The superficial branch breaks up into 2 branches- medial and lateral.
  1. The lateral branch provides 3 muscles: flexor digiti minimi brevis, third plantar interosseous, and fourth dorsal interosseous. It also provides the skin on the lateral side of little toe.
  2. The medial branch interacts together with the medial plantar nerve and provides the skin of the fourth cleft.
• Branches of the deep branch: It classes medially being located between the 3rd and fourth layers of the sole. It supplies nine muscles: abductor hallucis, 3 lumbricals (2nd, third, and fourth), and 5 interossei of the very first 3 intermetatarsal spaces.

Motor Innervation of The Medial And Lateral Plantar Nerves

Distribution of Pre-Axial And Post-Axial Nerves In The Palm And Sole