Basic Exam Competency 2 Muscles MMT Function

Gluteus Maximus

Extends and laterally rotates the hip

joint lower fibers assist in adduction

upper fibers assist in abduction

via IT tract act as knee stabilizer

Hip Flexors

When origin is fixed flex hip joint by flexing femur to trunk and may assist in lateral rotation and abduction of the hip joint

when insertion is fixed and acting bilaterally, flex hip joint by flexing trunk on the femur,

flexes, laterally rotates, and abducts hip joint

may assist in knee extension and tibial lateral rotation

flexes laterally rotates, and abducts hip

flexes, and assist in tibial medial rotation of the knee

Hip Adductors

Adduct the hip

Pectineus, adductor brevis, and adductor longus flex the hip

Adductor Magnus interior fibers assist hip flexion, posterior fibers assist hip extension

Gracilis flexes immediately rotates tibia on femur

Gluteus Medius

Hip abduction

Anterior fibers medically rotate and assist in hip flexion

Posterior fibers laterally rotates and assist in hip extension

Hip Medial Rotators

Medially rotate hip

Hip Lateral Rotators

Laterally rotate hip

Obturator externus may assist in hip adduction

Piriformis, obturator internus, gemelli superior, gemelli inferior may assist in hip abduction when hip is flexed

Piriformis may assist in hip extension

Medial Hamstrings

Flex and medially rotate knee

Extend and assist in medial rotation of hip

Lateral Hamstrings

Flex and laterally rotate knee

Lateral hamstrings extends and assists in lateral rotation of hip

Quadriceps

Extends the knee

Rectus femoris flexes the hip

Plantarflexor Group

Plantarflex ankle joint

Assist in knee flexion

Tibialis Anterior

Dorsiflexion of the ankle joint

Assists in inversion of foot

Tibialis Posterior

Inverts the foot

Assists in plantarflexion

Peroneus Longus and Brevis

Both: Everts and assists in plantarflexion

Longus: Depresses the head of first metatarsal

Extensor Digitorum Longus and Brevis

Extends MP joints

Assists in extending IP joints 2-5

Assists in dorsiflexion of ankle joint

Assists eversion of foot

Extends MP joints 1-4 (brevis)

Assist in extending IP joints 2-4 (brevis)

Flexor Digitorum Longus and Quadratus Plantae and Flexor Hallucis Longus

FDL: flexes DIP, PIP, MTP joints 2-5, assists in ankle plantarflexion and foot inversion

QP: modifies angle of pull of FDL and assists in flexion of DIP, PIP, MTP joints 2-5

FHL: flexes IP joint big toe, assists in MTP Flexion of big toe, assists in ankle plantarflexion and inversion