5 MusclesThere are 19 muscles and tendons (tendon attaches muscle to bone) muscles acting on the foot can be classified into extrinsic muscles, those originating on the anterior or posterior aspect of the lower leg, and intrinsic muscles, originating on the dorsal (top) or plantar (base) aspects of the foot.
6 Anterior compartment Muscle Origin Insertion Action tibialis anterior shaft of tibia and interosseous membranemedial cuneiform & base of first metatarsalextends the foot; inverts foot; supports medial longitudinal archextensor digitorumshaft of fibula and interosseous membraneextensor expansion of lateral four toesextends toes; dorsiflexes (extends) footextensor hallucis longusshaft of fibula & interosseous membranebase of distal phalanx of big toeextends big toe; dorsiflexes (extends) foot; inverts foot at subtalar and transverse tarsal joints
7 base of 1st MT & medial cuneiform Lateral Compartmentperoneus longusshaft of fibulabase of 1st MT & medial cuneiformplantar flexes foot; everts foot at subtalar & transverse tarsal joints; supports lateral longitudinal and transverse arches of footperoneus brevisbase of 5th metatarsal boneplantar flexes foot; everts foot at subtalar & transverse tarsal joints; supports lateral longitudinal arch
8 Posterior Compartment gastrocnemiusmedial and lateral condyles of femurby way of Achilles tendon to calcaneumplantar flexes foot; flexes legplantarislateral supracondylar ridge of femurcalcaneumsoleusshafts of tibia and fibulaby way of achilles tendon into calcaneumwith gastrocnemius & plantaris is powerful plantar flexor of foot; provides main propulsive force in walking & runningpopliteuslateral condyle of femurshaft of tibiaflexes leg; unlocks full extension of knee by laterally rotating femur on tibiaflexor digitorum longusdistal phalanges of lateral four toesflexes distal phalanges of lateral four toes; plantar flexes foot; supports medial and lateral longitudinal arches of footflexor hallucis longusshaft of fibulabase of distal phalanx of big toeflexes distal phalanx of big toe; plantar flexes foot; supports medial longitudinal arch
9 Dorsum of foot extensor digitorum brevis calcaneum by four tendons into the proximal phalanx of big toe and long extensor tendons to 2nd, 3rd and 4th toesextends toes
10 1st layer of sole abductor hallucis medial tubercle of calcaneum; flexor retinaculummedial side, base of proximal phalanx of big toeflexes, abducts big toe; supports medial archflexor digitorum brevismedial tubercle of calcaneummiddle phalanx of four lateral toesflexes lateral four toes; supports medial & lateral longitudinal archesabductor digiti minimimedial & lateral tubercles of calcaneumlateral side base of proximal phalanx 5th toeflexes, abducts 5th toe; supports lateral longitudinal arch
13 LigamentsThe lateral and medial ligaments of the ankle support and strengthen the joint.The deltoid ligament is stronger than the lateral ligaments. The strength of the deltoid prevents most eversions.
14 Primary Primary ligaments of ankle include: medial lateral Deltoid ligament - This strong ligament attaches to the medial malleolus. It has four parts named for the bones that they attach to: the tibionavicular, the tibiocalcaneal, the anterior tibiotalar, and the posterior tibiotalarCalcaneonavicular ligament (Spring Ligament) lateralSyndesmosis (includes AITFL, PITFL, TTFL, IOL, ITL)Anterior talofibular ligament (ATFL)Posterior talofibular ligament (PTFL)Calcaneal fibular ligament (CFL)Lateral talocalcaneal ligament (LTCL)
15 If you’ve ever sprained an ankle, you injured one or more of the ligaments that hold the joint together. The lateral ligaments are damaged more often than the stronger medial ligament.
21 Medial/LateralMedial arch is higher than the lateral longitudinal arch. It is made up by the calcaneus, the talus, the navicular, the three cuneiforms, and the first, second, and third metatarsalsThe lateral arch is composed of the calcaneus, the cuboid, and the fourth and fifth metatarsals