Medical term:

PTM

tib·i·al·is pos·ter·i·or mu·scle

(tib-ē-ā'lis pos-tēr'ē-ŏr mŭs'ĕl)

Most anterior (deepest) muscle of deep posterior (plantar flexor) compartment of leg; origin, soleal line and posterior surface of tibia, the head and shaft of the fibula between the medial crest and interosseous border, and the posterior surface of interosseous membrane; insertion, navicular, three cuneiform, cuboid, and second, third, and fourth metatarsal bones; action, plantar flexion and inversion of foot; nerve supply, tibial.
Synonym(s): musculus tibialis posterior [TA] .

tibialis posterior muscle

Leg muscle. Origin: anterior tibia and fibula. Insertion: navicular, cuneiform, and cuboid bones; metatarsals 2-4. Nerve: tibial (L4-L5). Action: inverts and plantarflexes foot.