Advanced Pectineus Quiz

Q1. Why can injury to the femoral nerve weaken pectineus without necessarily abolishing all of its motor input?

• The muscle has no motor innervation
• Its nerve supply comes exclusively from the sciatic nerve
• Pectineus is always supplied only by the tibial nerve
• Pectineus can have supplementary obturator-related innervation

Q2. What makes pectineus an important deep landmark in the femoral triangle?

• It forms part of the floor beneath the femoral vessels
• It encloses the sciatic nerve
• It forms the lateral border of the popliteal fossa
• It forms the inguinal ligament

Q3. How does the pubofemoral orientation of pectineus explain its combined actions?

• Its insertion on the tibia produces knee flexion
• Its line of pull can produce both adduction and flexion at the hip
• Its fibers cross the knee to extend the leg
• Its tendon passes behind the ankle

Q4. Why is the variable innervation of pectineus anatomically notable?

• It is the only lower limb muscle without nerve supply
• It differs from the typical obturator pattern of many medial thigh adductors
• It belongs to the posterior leg compartment
• It is always supplied by the tibial nerve

Q5. Which relationship is relevant when approaching the femoral vessels surgically in the proximal thigh?

• Pectineus lies within the femoral artery
• Pectineus lies deep to the femoral vessels
• Pectineus lies posterior to the knee joint
• Pectineus forms the skin over the triangle

Q6. Why does pectineus not directly produce knee movement?

• It crosses the knee but not the hip
• It inserts on the femur and does not cross the knee
• It inserts on the fibular head
• It inserts on the tibial tuberosity

Q7. How can pectineus contribute to frontal plane control of the thigh?

• By extending the knee
• By producing and controlling thigh adduction
• By plantarflexing the ankle
• By everting the foot

Q8. Which anatomical feature can help distinguish pectineus from adductor longus during proximal thigh dissection?

• It lies lateral to the iliopsoas
• It lies more proximally and inserts on the pectineal line
• It crosses the knee to the medial tibia
• It arises from the ischial tuberosity

Q9. Why can obturator or accessory obturator nerve variation matter clinically around pectineus?

• It can change the pattern of motor deficit after nerve injury
• It changes the bony insertion of the muscle
• It causes the muscle to cross the knee
• It eliminates arterial supply

Q10. Which statement best integrates pectineus anatomy?

• It is a tibial-nerve-supplied hamstring that flexes the knee
• It is a proximal pubofemoral muscle that adducts and flexes the hip and commonly receives femoral nerve supply
• It is a quadriceps muscle that inserts through the patellar ligament
• It is a common-fibular-nerve-supplied leg muscle that dorsiflexes the ankle