Lumbosacral Plexus

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Lumbosacral Plexus

• Chookiet Chalermpanpipat

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Spinal cord
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Lumbar segment
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Sacral segment
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Lumbar Plexus
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Lumbar Plexus

• First Lumbar nerve
• Lateral Femoral Cutaneous Nerve
• Femoral Nerve
• Genitofemoral Nerve
• Obturator Nerve
• Accessory Obturator Nerve

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Lumbar Plexus
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First Lumbar Nerve (L1)

• emerge from the lateral side of the Psoas
• Iliohypogastric Nerve (skin over the side of the
  buttock and pubis)
• Ilioinguinal Nerve (skin of the thigh, anterior
  scrotal anterior labial branch)

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Lumbar Plexus
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Intercostal Nerve
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Lateral Femoral Cutaneous Nerve (L2-3)

• Skin on the anterolateral surface of the thigh

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Femoral Nerve (L2-4)

• emerge from the lateral side of the psoas
• Iliacus
• Quadriceps Femoris
• Pectineus
• Sartorius
• Skin of the Thigh (front, medial)
• Hip Joint
• Knee Joint

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Genitofemoral Nerve (L1-2)

• Genital Branch (Cremaster, Scrotum, Labium Major,
  Thigh)
• Femoral Branch (Femoral triangle skin)

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Obturator Nerve (L2-4)

• emerge from the medial side of the psoas
• Adductor Muscles of the Thigh
• Gracilis
• Skin of the Thigh (medial)
• Hip Joint
• Knee Joint

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Accessory Obturator Nerve (L3-4)

• emerge from the medial side of the psoas
• Hip joint
• Pectineus

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Sacral Plexus
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Sacral Plexus

• Superior Gluteal Nerve
• Inferior Gluteal Nerve
• Nerve to Quadratus Femoris Inferior Gemellus
• Nerve to Obturator Internus Superior Gemellus
• Posterior Femoral Cutaneous Nerve
• Perforating Cutaneous Nerve
• Sciatic Nerve

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Sacral Plexus
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Superior Gluteal Nerve (L4-S1)

• Pass backward through the greater sciatic
  foramen above the piformis
• Gluteus Medius
• Gluteus Minimus

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Inferior Gluteal Nerve (L5-S2)

• Pass backward through the greater sciatic
  foramen below the piformis
• Gluteus Maximus

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Nerve to Quadratus femoris (L4-S1)

• Pass backward through the greater sciatic
  foramen below the piformis
• Inferior Gemellus
• Quadratus Femoris

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Nerve to Obturator Internus (L5-S2)

• Pass backward through the greater sciatic
  foramen below the piformis
• Superior Gemellus
• Obturator internus

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Sacral Plexus
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Posterior Femoral Cutaneous Nerve (S2-3)

• Pass backward through the greater sciatic
  foramen below the piformis
• Buttock
• Posterior surface of thigh

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Perforating Cutaneous Nerve (S2-3)

• Pass backward through sacrotuberous ligament
• Lower medial part of buttock

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Sciatic Nerve (L4-S3)

• Pass backward through the greater sciatic
  foramen below the piformis
• Largest nerve
• Consists of Peroneal and Tibial parts
• Hip
• Thigh Flexors
• Leg
• Foot

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Sacral Plexus
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Sacral Plexus

• Nerve to Piriformis
• Nerve to Levator Ani Coccygeus
• Nerve to Sphincter Ani Externus
• Pelvic Splanchnic Nerves
• Pudendal Nerve

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Sacral Plexus
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Nerve to Piriformis (S1-2)

• Piriformis

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Nerve to Levator Ani Coccygeus (S3-4)

• Levator Ani
• Coccygeus

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Nerve Sphincter Ani Externus (S4)

• Sphincter Ani Externus Skin

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Pelvic Splancchnic Nerve (S2-4)

• Pelvic viscera via inferior hypogastric plexus
  (contain parasympathetic preganglionic and
  sensory fiber)

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Pudendal Nerve (S2-4)

• Pass backward through the greater sciatic
  foramen below the piformis , cross ischial spine
  then enter the perineum through the lesser
  sciatic foramen
• Sensory to genitalia
• Motor to sphincter urethrae and external anl
  sphincter

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Sacral Plexus
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Sacral Plexus
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Sacral Plexus
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Pelvis
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Pelvis
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Pelvis
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Sacral Plexus
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Sacral Plexus
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Greater Sciatic Foramen
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Sciatic Foramen
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Cutaneous Nerve