Sports Med - Muscles of the Leg and Knee

For palpations

Soleus - Action

Plantarflex the ankle

Soleus - Origin

Soleal line; Proximal, posterior surface of tibia; Posterior aspect of head of fibula

Soleus - Insertion

Calcaneus via the Achilles tendon

Gastronemius - Action

• Flex the knee

• Plantarflex the ankle

Gastronemius - Origin

Posterior surface of the condyles of the femur

Gastronemius - Insertion

Calcaneus via the Achilles tendon

Plantaris - Action

• Weak plantarflex the ankle

• Weak flexion of the knee

Plantaris - Origin

Lateral supracondylar line of the femur

Plantaris - Insertion

Calcaneus via the Achilles tendon

Popliteus - Action

• Medially rotate the flexed knee

• Knee flexion

Popliteus - Origin

Lateral condyle of the femur

Popliteus - Insertion

Proximal, posterior aspect of the tibia

Semitendinous - Action

• Knee flexion

• Medial rotation of flexed knee

• Hip extension

• Assist medial rotation of the hip

• Posterior pelvis tilt

Semitendinous - Origin

Ischial tuberosity

Semitendinous - Insertion

Proximal, medial shaft of the tibia via the pes anserine tendon

Semimembranous - Action

• Knee flexion

• Medial rotation of flexed knee

• Hip extension

• Assist with medial rotation of the hip

• Posterior pelvis tilt

Semimembranous - Origin

Ischial tuberosity

Semimembranous - Insertion

Posterior aspect of medial condyle of the tibia

Biceps femoris Short head - Action

• Knee flexion

• Lateral rotation of flexed knee

Biceps femoris Short head - Origin

Lateral lip of linea aspera

Biceps femoris Short head - Insertion

Head of the fibula

Biceps femoris Long head - Action

• Knee flexion

• Lateral rotation of flexed knee

• Hip extension

• Assist with lateral rotation of hip

• Posterior pelvis tilt

Biceps femoris Long head - Origin

Ischial tuberosity

Biceps femoris Long head - Insertion

Head of the fibula

Rectus femoris - Action

• Knee extension

• Hip flexion

Rectus fermoris - Origin

Anterior inferior iliac spine (AIIS)

Rectus femoris - Insertion

Tibial tuberosity via the patella and patellar ligament/tendon

Vastus lateralis - Action

Knee extension

Vastus lateralis - Origin

Lateral lip of linea aspera; Gluteal tuberosity; Greater trochanter

Vastus lateralis - Insertion

Tibial tuberosity via the patella and patellar ligament/tendon

Vastus medialis - Action

Knee extension

Vastus medialis - Origin

Medial lip of linea aspera

Vastus medialis - Insertion

Tibial tuberosity via the patella and patellar ligament

Vastus intermedius - Action

Knee extension

Vastus intermedius - Origin

Anterior and lateral shaft of the femur

Vastus intermedius - Insertion

Tibial tuberosity via the patella and patellar ligament/tendon

Soleus

Gastrocnemius

Plantaris

Popliteus

Semitendinosus

Semimembranosus

Biceps femoris Short head

Biceps femoris Long head

Rectus femoris

Vastus lateralis

Vastus medialis

Vastus intermedius

Tibialis anterior - Action

• Invert the foot

• Dorsiflex the ankle

Tibialis anterior - Origin

• Lateral condyles of the tibia

• Proximal, lateral surface of tibia

• Interosseous membrane

Tibialis anterior - Insertion

Medial cuneiform and base of the first metatarsal

Extensor digitorum longus - Action

• Extend second through fifth toes

• Dorsiflex the ankle

• Evert the foot

Extensor digitorum longus - Origin

• Lateral condyle of the tibia

• Proximal, anterior shaft of the fibula

• Interosseous membrane

Extensor digitorum longus - Insertion

Middle and distal phalanges of second through fifth toes

Extensor hallucis longus - Action

• Extend the first toe

• Dorsiflex the ankle

• Invert the foot

Extensor hallucis longus - Origin

• Middle, anterior surface of the fibula

• Interosseous membrane

Extensor hallucis longus - Insertion

Distal phalanx of the first toe

Peroneal longus - Action

• Evert the foot

• Assist to plantarflex the ankle

Peroneal longus - Origin

• Head of the fibula

• Proximal two-thirds of lateral fibula

Peroneal longus - Insertion

• Medial cuneiform

• Base of the first metatarsal

Peroneal brevis - Action

• Evert the foot

• Assist to plantarflex the ankle

Peroneal brevis - Origin

Distal two-thirds of lateral fibula

Peroneal brevis - Insertion

Tuberosity of the fifth metatarsal