Learn: Muscles of the Lower Limb: Anatomy, Movements, and Innervation

What are the primary actions of muscles crossing the hip and knee joints?

Flexion, extension, abduction, adduction, circumduction, and rotation.

How are the muscles of the lower limb separated?

They are separated into three compartments covered by wide sheets.

What is the action of the anterior muscles of the lower limb?

They primarily flex the femur at the hip and extend the leg at the knee.

What is the action of the posterior muscles of the lower limb?

They primarily extend the thigh and flex the leg.

What is the innervation of the muscles crossing the hip region?

Innervated by the femoral nerve.

What is the primary action of the quadriceps femoris?

It is the prime extensor of the knee.

What muscle group is responsible for flexing and laterally rotating the thigh?

The iliopsoas group.

What are the boundaries of the femoral triangle?

Superior-medial: inguinal ligament; Lateral: sartorius; Inferior-medial: adductor longus; Floor: iliopsoas.

What contents are found in the femoral triangle from lateral to medial?

Femoral nerve, femoral artery, femoral vein, entrance of great saphenous vein, lymphatics.

What is the primary action of the gluteus maximus?

It extends and laterally rotates the thigh.

What is the innervation of the gluteal region muscles?

Innervated by the sacral plexus.

What is the primary action of the gluteus medius?

It abducts and medially rotates the thigh.

What is the role of the tensor fascia lata?

It helps to stabilize the hip and knee joints.

What is the primary action of the medial compartment muscles of the thigh?

They primarily adduct the thigh.

What is the common injury associated with the medial compartment muscles?

A 'pulled groin' when strained.

What is the primary action of the muscles crossing the hip and knee joints?

They facilitate movements such as flexion and extension of the thigh and leg.

What is the origin of the vastus lateralis muscle?

It originates from the greater trochanter and linea aspera of the femur.

What is the primary action of the pectineus muscle?

It flexes and adducts the thigh.

What is the role of the iliopsoas in lower limb movement?

It is a major flexor of the thigh at the hip joint.

What is the innervation of the adductor group of muscles?

Innervated by the obturator nerve.

What is the primary action of the sartorius muscle?

It flexes, abducts, and laterally rotates the thigh.

What is the significance of the IT band?

It is a thick lateral portion of the fascia lata, often associated with IT band syndrome in runners.

What is the major landmark for the sciatic nerve?

The sciatic nerve exits the pelvis deep to the piriformis muscle.

What are the primary actions of the hamstring muscles?

Hip extension and knee flexion.

What is the innervation of the hamstring muscles?

Sciatic nerve.

What is the origin of the hamstring muscles?

Ischial tuberosity.

What are the three main muscles of the hamstring group?

Biceps femoris, semitendinosus, and semimembranosus.

What is the insertion point of the biceps femoris?

Fibula.

What are the primary actions of the biceps femoris?

Flexes and laterally rotates the leg; extends the thigh.

What is the insertion point of the semitendinosus?

Tibia (medial condyle).

What are the primary actions of the semitendinosus?

Flexes and medially rotates the leg; extends the thigh.

What is the insertion point of the semimembranosus?

Tibia (medial condyle).

What are the boundaries of the popliteal fossa?

Superomedial: semitendinosus and semimembranosus; superolateral: biceps femoris; inferolateral: gastrocnemius (lateral head); inferomedial: gastrocnemius (medial head).

What are the contents of the popliteal fossa?

Popliteal artery and vein, sciatic nerve (tibial and common fibular branches), entrance of small saphenous vein.

What is the innervation of the anterior compartment of the leg?

Deep fibular (peroneal) nerve.

What is the primary action of the muscles in the anterior compartment of the leg?

Dorsiflexion of the ankle and extension of the toes.

What is the consequence of damage to the anterior compartment muscles?

Foot drop.

What is the primary action of the fibularis longus?

Everts and plantar flexes the foot.

What is the innervation of the lateral compartment of the leg?

Superficial fibular nerve.

What are the primary actions of the muscles in the posterior compartment of the leg?

Plantar flexion of the foot.

What is the innervation of the posterior compartment of the leg?

Tibial nerve.

What is the origin of the gastrocnemius?

Femur (medial and lateral condyles).

What is the primary action of the soleus?

Plantar flexes the foot.

What is the origin of the flexor hallucis longus?

Fibula (shaft).

What is the primary action of the tibialis posterior?

Plantar flexes and inverts the foot.

What are the three compartments of the leg?

Anterior, lateral, and posterior.

What is the primary action of the extensor digitorum longus?

Extends toes II-V and dorsiflexes the foot.

What is the primary action of the extensor hallucis longus?

Extends the big toe and dorsiflexes the foot.