Lower Limb Nerves

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Lower Limb Nerves

    • Cutaneous nerves of the lower limb
      • Lateral Femoral Cutaneous Nerve
        • Arises from the lumbar plexus (L2L3),
        • Innervates the skin on the anterior and lateral aspects of the thigh as far as the knee.
    • Posterior Femoral Cutaneous Nerve
        • Arises from the sacral plexus (S1S3),
        • passes through the greater sciatic foramen
        • Innervates the skin of the buttock, thigh, and calf.
    • Saphenous Nerve
        • Arises from the femoral nerve in the femoral triangle
        • Pierces the fascial covering of the adductor canal
        • Innervates the skin on the medial side of the leg and foot.
        • Is vulnerable to injury (proximal portion) during surgery to repair varicose veins.
    • Lateral Sural Cutaneous Nerve
        • Innervates the skin on the posterolateral side of the leg.
    • Medial Sural Cutaneous Nerve
        • Innervates the skin on the back of the leg and the lateral side of the ankle, heel, and foot.
    • Sural Nerve
        • Is formed by the union of the medial sural and lateral sural
        • Innervates the skin on the back of the legand the lateral side of the ankle, heel, and foot.
    • Superficial Peroneal Nerve
        • innervate the skin on the lateral side of the lower leg and the dorsum of the foot.
    • Deep Peroneal Nerve
        • Supplies anterior muscles of the leg and foot
        • Supplies skin of the contiguous sides of the first and second toes.
    • Branches of the lumbar and sacral plexuses
      • Obturator Nerve (L2–L4)
        • enters the thigh through the obturator foramen
        • Anterior Branch innervates the adductor longus, adductor brevis, gracilis, and pectineus muscles..
      • Femoral Nerve (L2–L4)
      • Superior Gluteal Nerve (L4–S1)
        • Arises from the sacral plexus
        • enters the buttock through the greater sciatic foramen
        • Innervates the gluteus medius and minimus, the tensor fasciae latae, and the hip joint.
      • Inferior Gluteal Nerve (L5–S2)
        • Arises from the sacral plexus
        • enters the buttock through the greater sciatic foramen
        • Innervates the overlying gluteus maximus.
      • Posterior Femoral Cutaneous Nerve (S1–S3)
      • Sciatic Nerve (L4–S3)
        • Arises from the sacral plexus
        • largest nerve in the body.
        • Divides into
          • tibial nerve
          • commonperoneal nerve
        • Enters the buttock through the greater sciatic foramen
        • Innervates the hamstring musclesby its tibial division, except for the short head of thebiceps femoris, which is innervated by its common peroneal division.
      • Common Peroneal (Fibular) Nerve (L4–S2)
        • divides into the deep peroneal and superficial peroneal nerves.
        • Is vulnerable to injury as it winds around the neck of the fibula, where it also can be palpated.
        • Gives rise to the
          • lateralsural cutaneous nerve
          • recurrent articular branch to the knee joint.
      • Superficial Peroneal (Fibular) Nerve
        • Innervates the peroneus longus and brevis muscles
        • innervates the skin on the lateral side of the lower leg and the dorsum of the foot.
      • Deep Peroneal (Fibular) Nerve
        • Innervates the anterior muscles of the leg
        • divides into
          • lateral branch
            • supplies the extensor hallucisbrevis and extensor digitorumbrevis
          • medial branch
            • accompanies the dorsalispedis artery
            • supply the skin on the adjacent sides of the first and second toes.
      • Tibial Nerve (L4–S3)
        • Descends through the popliteal fossa and then lies on the popliteus muscle.
        • Gives rise to three articular branches, which accompany genicular arteries to the knee joint.
        • Gives rise to the
          • medialsural cutaneous nerve
          • medial calcaneal branch to theskin of the heel and sole
          • articular branches to the ankle joint.
        • Terminates beneath the flexor retinaculum by dividing into the medial and lateralplantar nerves.
        • Medial Plantar Nerve
          • innervatesabductor hallucis and flexor digitorumbrevis muscles
          • Gives rise to common digital that supply
            • flexorhallucisbrevis
            • firstlumbrical
            • skin of the medial three and one-half toes.
        • Lateral Plantar Nerve
          • innervatesthe quadratusplantae and the abductor digitiminimimuscles.
          • Divides into a
          • superficial branch, which innervates the flexor digitiminimibrevis,
          • deep branch, which innervates the
            • plantar and dorsal interossei
            • lateral three lumbricals
            • adductorhallucis.
      • Surgical Anatomy
        • Damage to the obturator nerve
          • causesweakness of adduction and a lateral swinging of the limb during walking because of the unopposed abductors.
        • Damage to the femoral nerve
          • causesimpaired flexion of the hip and impaired extension of the leg resulting from paralysis of the quadriceps femoris.
        • Injury to the superior gluteal nerve
          • causesweakened abduction of the thigh by the gluteus medius
          • adisabling gluteus medius limp, and gluteal gait.
        • Damage to the sciatic nerve
          • causes impaired
            • extension at the hip
            • flexion at the knee
            • dorsiflexion and plantar flexion at the ankle,
            • inversion and eversion of the foot
          • peculiar gait because of increased flexion at the hip to lift the dropped foot off the ground.
        • Damage to the common peroneal (fibular) nerve
          • occur as a result of fracture of the head or neck of the fibula
          • The nerve damage results in
            • foot drop (loss of dorsiflexion)
            • loss of sensation on the dorsum of the foot and lateral aspect of the leg
            • causes paralysis of all muscles in the anterior and lateral compartments of the leg (dorsiflexor and evertor muscles of the foot).
        • Damage to the superficial peroneal (fibular) nerve
          • causes no foot drop
          • causeloss of eversion of the foot.
        • Damage to the deep peroneal (fibular) nerve
          • results in foot drop (loss of dorsiflexion)
          • causescharacteristic high-stepping gait.
        • Damage to the tibialnerve causes
            • loss of plantar flexion of the foot
            • impaired inversion resulting from paralysis of the tibialis posterior
            • causes a difficulty in getting the heel off the ground and a shuffling of the gait
            • It results in a characteristic clawing of the toes and sensory loss on the sole of the foot, affecting posture and locomotion.


            Muscles and Nerves of Lower Limb
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            Blood Vessels and Nerves of the Leg
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            Nerves Of The Lower Leg 3D – Everything You Need To Know – Dr. Nabil Ebraheim
            Educational video showing 3D animation of the nerves of the lower leg
            Anatomy Series, Innervation of the Lower Limb by Dr. Shakti Chandra
            Anatomy Series, Innervation of the Lower Limb by Dr. Shakti Chandra
            Lower Extremity Nerves
            This is a video of the Lower Extremity Spinal Nerves