Muscles and Circulation of Lower Limb

Muscles Of The Lower Limb

• Quadriceps Femoris:
  • Composed of four muscles: rectus femoris, vastus lateralis, vastus medialis, vastus intermedius.
  • Primary function: knee extension.
• Hamstrings:
  • Comprises biceps femoris, semitendinosus, semimembranosus.
  • Primary function: knee flexion and hip extension.
• Adductors:
  • Includes adductor longus, adductor brevis, adductor magnus, gracilis.
  • Function: hip adduction.
• Gluteal Muscles:
  • Gluteus maximus, gluteus medius, gluteus minimus.
  • Functions: hip extension (maximus), abduction (medius and minimus).
• Calf Muscles:
  • Gastrocnemius and soleus.
  • Function: plantarflexion of the foot.
• Tibialis Anterior:
  • Primary function: dorsiflexion of the foot.

Circulation In The Lower Limb

• Major Arteries:
  • Femoral artery: supplies the thigh.
  • Popliteal artery: continuation of femoral artery behind the knee.
  • Anterior tibial artery: supplies the anterior compartment of the leg.
  • Posterior tibial artery: supplies the posterior compartment.
  • Fibular (peroneal) artery: branches from the posterior tibial artery.
• Venous System:
  • Deep veins accompany the arteries; include femoral, popliteal, and tibial veins.
  • Superficial veins: great saphenous vein (longest in the body) and small saphenous vein.
• Venous Return:
  • Valves prevent backflow; calf muscle pump aids in venous return.

Anatomy Of The Leg

• Divisions:
  • Divided into three compartments: anterior, lateral, and posterior.
• Bones:
  • Tibia: larger, weight-bearing bone.
  • Fibula: thinner, provides lateral stability.
• Joints:
  • Knee joint: hinge joint between femur, tibia, and patella.
  • Ankle joint: formed by tibia, fibula, and talus; allows dorsiflexion and plantarflexion.
• Fascia:
  • Deep fascia surrounds muscles and compartments, aiding muscle function and venous return.
• Nerves:
  • Sciatic nerve splits into tibial and common fibular nerves, innervating lower limb muscles.

Muscles Of The Lower Limb

• Quadriceps Femoris
  • Comprised of four muscles: rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius.
  • Primarily responsible for knee extension.
• Hamstrings
  • Consists of three muscles: biceps femoris, semitendinosus, and semimembranosus.
  • Primarily facilitates knee flexion and hip extension.
• Adductors
  • Includes adductor longus, adductor brevis, adductor magnus, and gracilis.
  • Main function is hip adduction.
• Gluteal Muscles
  • Composed of gluteus maximus, gluteus medius, and gluteus minimus.
  • Gluteus maximus is primarily involved in hip extension, while medius and minimus are responsible for hip abduction.
• Calf Muscles
  • Includes gastrocnemius and soleus.
  • Responsible for plantarflexion of the foot.
• Tibialis Anterior
  • Primarily facilitates dorsiflexion of the foot.

Circulation In The Lower Limb

• Major Arteries
  • The femoral artery supplies the thigh and continues as the popliteal artery behind the knee.
  • Anterior tibial artery provides blood to the anterior compartment of the leg.
  • Posterior tibial artery supplies the posterior compartment, while the fibular artery branches off from it.
• Venous System
  • Deep veins mirror the arteries, including femoral, popliteal, and tibial veins.
  • Superficial veins consist of the great saphenous vein (the longest vein in the body) and the small saphenous vein.
• Venous Return
  • Valves within veins prevent backflow, with the calf muscle pump aiding overall venous return.

Anatomy Of The Leg

• Divisions
  • The leg is divided into three compartments: anterior, lateral, and posterior.
• Bones
  • Tibia is the larger, weight-bearing bone, while the fibula is thinner and provides lateral stability.
• Joints
  • The knee joint acts as a hinge joint, connecting the femur, tibia, and patella.
  • The ankle joint is formed by the tibia, fibula, and talus, allowing for dorsiflexion and plantarflexion.
• Fascia
  • Deep fascia surrounds muscles and compartments, supporting muscle function and helping with venous return.
• Nerves
  • The sciatic nerve bifurcates into the tibial and common fibular nerves, innervating the muscles of the lower limb.

This quiz covers the muscles of the lower limb, including the quadriceps, hamstrings, adductors, gluteal muscles, calf muscles, and tibialis anterior. It also delves into the major arteries responsible for circulation in this area. Test your knowledge on these essential components of the lower limb anatomy.