Gastrocnemius Flashcards

Explore gastrocnemius anatomy, including its two heads, femoral attachments, Achilles tendon, tibial nerve supply, actions, and clinical relevance.

Card 1 of 28Question

Which compartment of the leg contains the gastrocnemius?

The superficial posterior compartment of the leg.

In This Section

1. Which compartment of the leg contains the gastrocnemius?

The superficial posterior compartment of the leg.

2. How many heads does the gastrocnemius muscle have?

Two heads, medial and lateral.

3. Which two muscles form the triceps surae?

Gastrocnemius and soleus.

4. What is the origin of the medial head of gastrocnemius?

The posterior femur superior to the medial condyle, including the adjacent popliteal surface.

5. What is the origin of the lateral head of gastrocnemius?

The lateral aspect of the lateral femoral condyle and adjacent supracondylar region.

6. Which tendon receives the converging fibers of gastrocnemius?

The calcaneal tendon, also called the Achilles tendon.

7. Where does the gastrocnemius insert?

The posterior surface of the calcaneal tuberosity through the calcaneal tendon.

8. Which two joints are crossed by gastrocnemius?

The knee and ankle joints.

9. What is the primary action of gastrocnemius at the ankle?

Plantarflexion of the foot.

10. What action does gastrocnemius produce at the knee?

Flexion of the leg at the knee joint.

11. Which nerve innervates gastrocnemius?

The tibial nerve.

12. Which spinal nerve roots primarily supply gastrocnemius?

S1 and S2.

13. Which arteries primarily supply gastrocnemius?

The medial and lateral sural arteries, branches of the popliteal artery.

14. Which venous system primarily drains gastrocnemius?

The gastrocnemius veins, which usually drain into the popliteal vein.

15. Which muscle lies immediately deep to gastrocnemius?

The soleus muscle.

16. Which anatomical space is bounded inferiorly by the two heads of gastrocnemius?

The popliteal fossa.

17. Which neurovascular structures lie deep to gastrocnemius in the popliteal region?

The tibial nerve and popliteal vessels.

18. Which superficial vein commonly ascends between the gastrocnemius heads before draining into the popliteal vein?

The small saphenous vein.

19. Which sensory nerve commonly descends between the heads of gastrocnemius?

The medial sural cutaneous nerve, which contributes to the sural nerve.

20. Why is gastrocnemius more effective in plantarflexion when the knee is extended?

Knee extension lengthens the muscle, improving its capacity to generate plantarflexion force.

21. How does bending the knee affect the plantarflexion contribution of gastrocnemius?

It shortens the muscle and reduces its force-generating capacity through active insufficiency.

22. During which activity does gastrocnemius generate substantial plantarflexion force?

Rising onto the toes, running, and jumping.

23. What is the role of gastrocnemius during the push-off phase of gait?

It generates plantarflexion force that contributes to forward propulsion.

24. What is the principal functional difference between gastrocnemius and soleus?

Gastrocnemius crosses the knee and ankle, whereas soleus crosses only the ankle.

25. Which deep tendon reflex primarily tests the S1 nerve root through gastrocnemius and soleus?

The Achilles tendon reflex, also called the ankle jerk reflex.

26. What is a common site of gastrocnemius strain known as tennis leg?

The medial gastrocnemius myotendinous junction.

27. Which anatomical structure may be compressed by an anomalous gastrocnemius attachment in popliteal artery entrapment syndrome?

The popliteal artery.

28. What is a fabella in relation to gastrocnemius?

A variable sesamoid bone located within the tendon of the lateral gastrocnemius head.