Neurological Examination of the Pelvic Floor

Question 1

Lumbosacral neurologic examination should include:

Answer 1

• motor strength PFM and pelvic girdle musculature
• sensory function of lumbar and sacral dermatomes
• deep tendon and sacral reflexes

Question 2

Evaluation of sensory function:

Answer 2

• test for light touch, pin prick, and temperature

Dermatomes to include:

1. Iliohypogastric (T12 - L1)
2. Illioinguinal (L1-L2)
3. Genitofemoral (L1-2)
4. Femoral (L2-3)
5. Lateral femoral cutaneous (L2-3)
6. posterior femoral cutaneous-sensory to perineum, buttock, posterior thigh, and limb
7. Obturator nerve (L3-4, S1)
8. Pudendal nerve (S2-4)

Question 3

Describe the Iliohypogastric nerve:

Answer 3

• T12- L1
• sensory supply to the superior pubis, lower abdomen into groin, and lateral perineum
• Passes through psoas, along surface of quadratus, through transverse abdominis (TrA) muscle and internal obliques to the ASOA, and then runs horizontally under the external oblique
• potential for entrapment d/t incision/scars
• injury from appendectomies, hysterectomies

Question 4

Describe the Ilioinguinal nerve:

Answer 4

• L1-2
• sensory supply to mons pubis and upper aspect of labia majora, superior medial aspect of the thigh, inguinal crease; has overlap with the genitofemoral nerve
• accompanies the iliohypogastric nerve crossing the internal oblique aponeurosis toward the symphysis along the round ligament
• injury from pregnancy, abdominal incisions.

Question 5

Describe the Genitofemoral nerve:

Answer 5

• (L1-2) sensory supply to mons pubis/labia majora and femoral triangle area
• pierces psoas and transversalis splitting into Genital branch and femoral branch
• potential for entrapment d/t incisions/scars/psoas spasm/symphyseal misalignment
• injury from c-section, hernia repair

Question 6

Femoral Nerve

Answer 6

• L2-3
• sensory to anteriomedial thigh, prepatellar region and medial calf
• emerges from under psoas and under inguinal ligament
• potential for entrapment through the inguinal ligament, worse with hip abduction and external rotation as with the delivery or surgical procedures

Question 7

Lateral femoral cutaneous nerve:

Answer 7

• L2-3
  sensory to anterolateral thigh
• lateral border of psoas, crosses iliacus to ASIS and under inguinal ligament over sartorius into thigh

Question 8

Posterior femoral cutaneous

Answer 8

• sensory to perineum, buttock, posterior thigh, and limb

Question 9

Obturator nerve

Answer 9

• L3,4, S1
• sensory from groin to inner thigh
• L3/4 = sensory supply to anterior knees
• S1 sensory supply to the soles of the feet
• travels within the psoas, deep toward the sacroiliac joint, then superficial to the obturator internus and through the obturator notch to medial thigh
• potential damage from pelvic lymph node dissection, pelvic retractors, THR, difficult delivery

Question 10

Pudendal Nerve:

Answer 10

• S2-4
• sensory supply to the perineum and perianal skin
• travels out of the greater sciatic notch between piriformis and coccygeus, then enters back into the pelvis through the lesser sciatic notch
• inferior rectal/hemorrhiodal branch innervates the posterior perineum
• perineal branch innervates the middle perineal region
• dorsal nerve to the clitoris travels to the clitoris
• potential for injury during childbirth, prolonged increases in IAP (constipation, heavy lifting, prolonged sitting or cycling, and surgery

Question 11

Deep Tendon reflexes:

Answer 11

• L3-4 = Patellar
• Achilles tendon reflex = L5, S1, S2
• Babinski sign = plantar toe reflex
• Anal wink